Larry Dighera
November 13th 07, 01:15 PM
Are UAVs Ready For "Prime Time" in the NAS?
Will the "pilots" of this UAV face FAA Enforcement Action?
How do UAV pilots "see-and-avoid" during night operations?
Crash highlights risks of uncrewed aircraft
31 October 2007
NewScientist.com news service
A mix-up between fuel and camera controls caused a 4.5-tonne
uncrewed aircraft to smash into a residential area near the town
of Nogales, Arizona. No one was hurt but the incident raises
serious questions about the safety of flying uncrewed aerial
vehicles (UAVs) in civilian airspace and could hamper plans to use
them more widely.
On 25 April 2006, a Predator B surveillance UAV belonging to US
Customs and Border Protection (CBP) was patrolling the Mexican
border when the ground pilot's radio-control console froze,
prompting him to switch to a back-up. Last week the US National
Transportation Safety Board released a damning report into how the
change caused the plane to crash.
The lever controlling fuel supply on the first console was set up
to control the video camera on the second. When the pilot switched
consoles, he failed to notice the difference, which caused the
engine to cut out. The report slammed the CBP for differences on
the consoles, poor pilot training, the failure to use a checklist
when switching consoles, and the lack of a back-up pilot.
Some aerospace firms hope to sell UAVs (currently used mainly by
the military) for monitoring floods, surveillance and firefighting
(New Scientist, 1 December 2006, p 26). The report highlights why
this might be a bad idea. It will also make commercial success
harder to pull off. There could be an expensive regulatory
backlash, says Bruno Esposito of the European UAV Working Group.
"I hope this will not lead to a requirement for very expensive
ground control avionics. That will kill this market."
http://www.ntsb.gov/ntsb/GenPDF.asp?id=CHI06MA121&rpt=fa
National Transportation Safety Board
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Model/Series Aircraft Manufacturer
Aircraft Information Summary
Sightseeing Flight: Air Medical Transport Flight:
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Brief narrative statement of facts, conditions and circumstances
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History of Flight
On April 25, 2006, about 0350 mountain standard time, a MQ-9 (Predator
B) aircraft, serial number
BP-101, call sign OHAMA 10, collided with the terrain approximately 10
nautical miles northwest of
the Nogales International Airport (OLS), Nogales, Arizona. The
unmanned aircraft system (UAS) was
owned by U.S. Customs and Border Protection (CBP) and operated as a
public-use aircraft. The
flight was operating in night visual meteorological conditions (VMC).
An instrument flight rules
(IFR) flight plan had been filed and activated for the flight. The
unmanned aircraft (UA)
sustained substantial damage. There were no injuries to persons on the
ground. The flight
originated from the Libby Army Airfield (FHU), Sierra Vista, Arizona,
at 1851, on April 24, 2006.
The wreckage was located at 0630.
The flight was being flown from a ground control station (GCS) located
at FHU. The GCS contains
two nearly identical pilot payload operator (PPO) consoles, PPO-1 and
PPO-2. Normally, a certified
pilot controls the UA from PPO-1, and the camera payload operator
(typically a U.S. Border Patrol
agent) controls the camera, which is mounted on the UA, from PPO-2.
Although the aircraft control
levers (flaps, condition lever, throttle, and speed lever) on PPO-1
and PPO-2 appear identical,
they may have different functions depending on which console controls
the UA. When PPO-1 controls
the UA, movement the condition lever to the forward position opens the
fuel valve to the engine;
movement to the middle position closes the fuel valve to the engine,
which shuts down the engine;
and movement to the aft position causes the propeller to feather. When
the UA is controlled by
PPO-1, the condition lever at the PPO-2 console controls the camera's
iris setting. Moving the
lever forward increases the iris opening, moving the lever to the
middle position locks the
camera's iris setting, and moving the lever aft decreases the opening.
Typically, the lever is set
in the middle position.
In addition to the pilot and payload operator, other personnel present
in the GCS were an avionics
technician and a sensor operator, both of whom are General Atomics
Aeronautical Systems, Inc.
(GA-ASI) employees. GA-ASI manufactures the Predator B and was
contracted by CBP to fly and
maintain BP-101.
The flight was originally scheduled to take off at 1700 but was
delayed because of the inability to
establish a communication link between the UA and PPO-1 during initial
power up. The avionics
technician stated he powered down the UA and downloaded the system
status. He then recycled the
power on PPO-1 and PPO-2, but again he was not able to establish an
uplink on PPO-1. The
technician did not attempt to gain an uplink on PPO-2 during either of
these power-ups. The
technician reported that he again captured the system status data on
his laptop and called his
supervisor at the manufacturer's facility in California for
assistance. He reported that his
supervisor and the technical support personnel with whom he spoke had
not seen this type of problem
before. They recommended that he switch the main processor cards
between PPO-1 and PPO-2. The
No No
Airplane Predator B General Atomics
Off Airport/Airstrip
MST 0350 85621 AZ Nogales
NTSB Accident
None 04/25/2006
None CHI06MA121
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technician stated that he did this, powered up the system, and was
able to establish an uplink on
both PPO-1 and PPO-2. He stated that everything operated normally at
this point, and he went off
duty at 2000.
Because the UA typically stays airborne for extended periods of time,
more than one pilot is
scheduled to fly during each mission. The pilots rotate flying duties
every couple of hours
throughout the duration of the flight. The pilot who was flying the
initial part of the accident
flight, including the takeoff, was not the accident pilot. The
accident pilot reported that he was
scheduled to work from 1900 on April 24, 2006, until 0500 on the day
of the accident. The accident
pilot reported that he took control of the flight at 1900 when BP-101
was already airborne and
operating in the temporary flight restriction (TFR) airspace. He
reported that he flew from 1900
until 2100. At 2100, another pilot resumed control of the flight. The
accident pilot took control
of the flight again at 0300 and was scheduled to fly until 0500. He
stated that the change-over
briefing at 0300 was normal and that nothing had changed with the
flight.
He reported that, shortly after he resumed control of the flight, the
lower monitor screen went
blank on PPO-1. The screen then reappeared, but the telemetry
(transmitted data) was locked up, so
he decided to switch control of the UA to PPO-2. The pilot stated that
he informed the Border
Patrol agent who was at PPO-2 that he needed to switch positions. The
Border Patrol agent stated
that he moved away from PPO-2 and left the GCS. The pilot stated that
he verified the ignition was
"hot" on PPO-2 and that the stability augmentation system was on. He
reported that, at some point,
he used his cell phone to call another pilot (who had been his
instructor) to discuss what was
going on. At the time, the instructor was in a hangar building across
the ramp.
Checklist procedures state that there should be pilots in both the
PPO-1 and PPO-2 seats before
switching control of the UA from one PPO to the other. CBP stated that
its procedures call for the
avionics technician to assume the duties of a co-pilot for the purpose
of assisting with the
checklist items before switching control from one PPO to the other.
This did not occur during the
accident sequence.
The pilot stated that he did not use the checklist when making the
switch. Checklist procedures
state that before switching operational control between the two
consoles, the pilot must match the
control positions on the new console to those on the console that had
been controlling the UA. The
pilot stated in an interview that he was in a "hurry" and that he
failed to do this. The condition
lever on PPO-2 was in the fuel cutoff position when the switch from
PPO-1 to PPO-2 occurred. As a
result, the fuel was cut off to the UA engine when control was
transferred to PPO-2.
The pilot stated that, after the switch to the PPO-2 console, he
noticed that the UA was not
maintaining altitude, but he did not know why. He decided to shut down
the ground data terminal
(GDT) so that the UA would begin its lost-link procedure. This
procedure called for the UA to
autonomously climb to 15,000 feet above mean sea level (msl) and fly a
predetermined course until
contact could be reestablished. With no engine power, the UA continued
to descend below
line-of-sight (LOS) communications, and further attempts to
reestablish contact with the UA were
not successful.
The pilot reported that the instructor pilot entered the GCS shortly
after the avionics technician
turned off the GDT. He informed the instructor of what occurred, and
the instructor looked at the
controls and stated that the controls were not positioned correctly.
The instructor tried to
reestablish contact with BP-101 in both the GCS and the mobile GCS
(MGCS); however, BP-101 had
already descended below LOS, and contact could not be reestablished.
The avionics technician who was positioned at the multifunction
workstation (MFW) in the rear of
the GCS recalled the events, as follows. He stated that he heard the
pilot say that PPO-1 had
locked up. He then noticed that the chart display on his monitor had
locked up. The technician
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stated that he walked up to the front of the GCS and looked at the
status-warning screen on PPO-2,
which indicated that PPO-1 was locked up. He advised the pilot that
they needed to switch control
to PPO-2. He then went back to the MFW to open up another program,
which showed him what processes
were running on PPO-1 so that he could record this information. The
technician then returned to
the front of the GCS, at which time the pilot was using his cell phone
to call for support. He
advised the pilot again that they needed to switch control from PPO-1
to PPO-2. The technician
stated that the pilot switched control to PPO-2 and that the pilot
then stated that PPO-2 was also
locked up. He then told the pilot that they needed to send the UA into
its lost-link procedure by
shutting off the GDT. The technician stated that he pulled the plug to
the PPO-1 processor rack
then switched off the circuit breaker to the GDT. He told the pilot
that they needed to go into
the MGCS to try and recover the UA because the MGCS was up and running
for the entire flight. He
stated that he went into the MGCS to make sure that it was ready for
the pilot, and, when he
returned to the GCS, the other pilot was already there. He stated that
he continued to work with
the pilots to try and establish link with the UA.
Personnel information
The pilot, age 35, was employed by GA-ASI. The pilot held a commercial
pilot certificate, with
single-engine land, multi-engine land, and instrument ratings. He also
held a certified flight
instructor certificate with single-engine land, multi-engine land, and
instrument ratings, along
with an advanced ground instructor certificate. The pilot's most
recent Federal Aviation
Administration (FAA) first-class medical certificate was issued on May
31, 2005. The medical
certificate did not contain any limitations.
The pilot reported that he had 3,571 total flight hours, which
included 519 hours of Predator A
flight time and 27 hours of Predator B hours. The 27 hours of Predator
B time were flown
throughout 9 flights, 5 hours of which were training flights. The 5
hours of training were
conducted at the GA-ASI facility in Palmdale, California. There were
no Predator B simulators
available before the accident, so all of the flight training was
accomplished with the actual UAS.
At the time of the accident, CBP flight time requirements were 200
hours manned aircraft time and
200 hours UAS flight time. The UAS time was not required to be type
specific.
CBP required that "All operators shall also be certified by the
contractor as being fully capable
of maintaining and operating the 'Predator B' UA and its associated
equipment." GA-ASI used a
training syllabus, which had been approved by the Air Force, to train
pilots to operate the CBP UAS
for the Air Force. Once a pilot completed the training syllabus,
GA-ASI would present the
completed training records, which had been approved by the Air Force
Government Flight
Representative (GFR), to CBP. CBP would then either approve or
disapprove the specific pilot to
operate the CBP UAS. At the time of the accident, CBP did not have a
fully trained GFR on its
staff.
The pilot's training was documented on several different Department of
Defense and Air Force forms.
DD Form 2627 indicated that on February 17, 2006, the Air Force GFR
approved the pilot to begin
MQ-9 training. AFMC Form 68 MQ-9 Pilot Conversion indicated the pilot
completed the training on
March 24, 2006. On May 5, 2006, which was after the date of this
accident, the Air Force GFR
disapproved the pilot's request for approval to act as a MQ-9 pilot
and cited that the pilot had
not completed some training modules.
Five of the training events listed on the AFMC Form 68 MQ-9 Pilot
Conversion form were not
accomplished during the pilot's training. Those events were: Mission
Planning/Briefing/Debriefing, Handover Procedures - Ground, Mission
Monitor/MFW Procedures,
Operational Mission Procedures, and Handover Procedures - Airborne.
The training syllabus states
that Air Force grading criteria are used to evaluate the pilot's
performance during training.
According to CBP, GA-ASI contacted their person who was being trained
as a GFR and requested that
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the accident pilot be added to CBP's approved pilot list before the
Air Force GFR approval. CBP
stated that their GFR trainee gave GA-ASI a verbal approval so that
the pilot could operate the CBP
UAS but only when an instructor pilot was physically present in the
GCS. This verbal approval was
not standard practice for CBP.
Nowhere in the training records provided to the Safety Board does it
list specific training on
procedures to switch control of the UAS from one PPO to the other. As
previously stated, the
majority of the pilot's UAS experience was with the Predator A. The
Predator B has different and a
more complex engine and engine controls than the Predator A. Also, the
control console for the
Predator A does not have a condition lever that needs to be matched up
between the PPOs when
switching from one PPO to the other.
Aircraft Information
The UA was a MQ-9 (Predator B) aircraft, serial number BP-101,
manufactured by GA-ASI. The
accident occurred on the UA's 118th flight. The UA typically flew
14-hour missions, 4 days per
week, and a shorter mission on the 5th day. According to the flight
record, the engine and
airframe had accumulated a total of 498 and 1,217 hours, respectively.
The Predator B is approximately 36 feet in length with a wingspan of
66 feet. The maximum gross
weight is 10,000 pounds. The UA can stay airborne for more than 30
hours at altitudes up to 50,000
feet. The fuselage is a composite structure of impregnated graphite
skin and Nomex honeycomb
stiffening panels. The fuselage incorporated an avionics bay, fuel
bays, an accessory bay, landing
gear bays, and an engine bay.
The fuel tank bays consisted of three inline bladder fuel tanks
located in the forward, header, and
aft fuel tank bays. Each wing also contained an inboard and an
outboard fuel tank. The aircraft
total fuel capacity was 3,920 pounds.
The UA was powered by a Honeywell TPE 331-10Y turboprop engine. The
engine is mounted at the rear
of the fuselage and produces 900-shaft horsepower. The engine controls
and indicators located in
the GCS were similar to the engine controls for a manned aircraft. The
engine was equipped with an
in-flight restart capability.
A three-bladed, variable pitch McCauley 36FR36C606-B propeller was
installed on the aircraft. The
pusher propeller was full-feathering and capable of reverse pitch.
The most recent maintenance performed on BP-101 was a 200-hour
inspection that was performed on
April 21, 2006. Interviews with GA-ASI and CBP personnel revealed
that, due to limited funding,
there was virtually no stock of spare parts at FHU for the BP-101.
They stated that, when they
needed a part, they would have to wait for it to be shipped from the
manufacturer.
At the time of the accident, CBP was unable to certify to the FAA that
BP-101 was airworthy.
Because of national security issues and past experience with similar
UASs, the FAA temporarily
waived this requirement for the issuance of the Certificate of Waiver
or Authorization (COA) to
operate in the National Airspace System (NAS).
UA Control System
The accident UA was operated by means of C-band (signal
communications), which provided for LOS
control. The UA descended below LOS after the engine stopped producing
power.
A secondary means of control was provided through the Iridium
satellite communication system.
However, in the Iridium control mode, there is limited ability to
control the UA; under Iridium
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control, the only way to control the UA is by using autopilot hold
modes. All hold modes
(altitude, airspeed, and heading) must be active for the Iridium
satellite to control of the UA.
The hold modes were on before the lost link. If both the Iridium and
LOS uplinks are active, the
LOS link has priority, and the Iridium data is ignored. However, when
the fuel was cut off to the
engine and the UA began shedding electrical equipment to conserve
battery power, the Iridium system
was one of the items that was shed. The UA is also equipped with an
auto-ignition system, but this
system will not work unless the Iridium system is operable.
Lost Link
A lost data link occurs when the UA is no longer receiving
command/control data from the GCS. In
the event of a lost data link between the GCS and UA, the UA will
enter a flightpath known as the
lost-link profile, which is predetermined and performed autonomously,
until the GCS operation can
be restored and a data link can be reestablished. The lost-link
profile, including the initial
lost-link heading and altitude, is uploaded to the UA before every
mission
Following the accident, it was determined that there were three
lost-link profiles stored on the
computer in the GCS; only one of which could be active at any given
time. The area in which the UA
was operating would dictate which profile would be uploaded. The pilot
can change any or all of
this information during the flight. One of the pilots stated that,
during the flight, he moved the
first waypoint in the profile to coincide with the second waypoint. It
was not unusual for the
pilots to move the first waypoint, depending on the location of the
UA.
On occasions other than the accident, when the UA goes into a
lost-link profile, it will initially
turn to a preset lost-link heading, go to full power, and climb for 51
seconds at a commanded
airspeed of 105 knots. If the UA is within 200 feet of the lost-link
altitude (or higher), this
first step is skipped. In the next step, the system generates a
waypoint at the preset lost-link
altitude, 2.5 nautical miles from the location where the UA started
the lost-link profile, in the
direction of the lost-link heading, and the UA proceeds to that
waypoint. Once the UA reaches that
waypoint and the lost-link altitude (or 30 minutes later, whichever
comes first), it will proceed
to fly the remainder of the lost-link profile. This portion of the
lost-link profile consists of a
predetermined series of altitudes and locations, which form a path
that the UA will autonomously
fly. If a data link cannot be reestablished, the UA cannot land, and
it will eventually run out of
fuel and crash at some location along the lost-link profile route.
Another contractor, Organizational Strategies, Inc. (OSI), provided
the coordinates for the
lost-link waypoints to CBP. OSI reported that it developed the
waypoints using an Internet
satellite website. CBP reported that it also used the same Internet
satellite website to verify
the location of the waypoints. According to this website, some of the
website's imagery is 1 to 3
years old. Neither OSI nor CBP used additional methods to confirm that
the waypoints were not
located over populated areas.
The COA lists the following lost-link procedures:
1. Turn northward toward and proceed within the TFR to the appropriate
Lost Link Location.
2. Hold for 30 minutes.
CBP shall ensure that the UAS remains at the last assigned altitude
and within the TFR at
all times, including while holding.
3. Proceed within the TFR to the adjacent Lost Link Location in the
direction of Libby AAF
[Army Airfield] (and hold as indicated in step 2). Procedure steps 2 &
3 shall be repeated until
the UAS has entered R2303 [restricted airspace].
4. Depending on the status of R2303, the UAS shall:
a. Hold at the Lost Link Location in Area 2 until R2303 becomes
active, or
b. Enter R2303, and
Then cancel IFR services with ATC [air traffic control] and proceed to
Libby AAF, in
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accordance with the appropriate Certificate of Authorization.
Engine Controls
The condition lever, which is installed in both the PPO-1 and PPO-2
consoles, serves a different
function depending on whether the station is being used by the payload
operator or by the pilot.
In the payload operator configuration, the lever is used to control
the iris of the camera. Moving
the lever forward increases the iris opening, moving the lever to the
middle position locks the
camera's iris setting, and moving the lever aft decreases the opening.
In the pilot configuration, the lever is used to control the engine
fuel valve and the propeller
feather servo. When in the pilot configuration, the lever has a linear
analog range from 0 to 100
percent, which is divided into thirds: "normal," "shutdown," and
"feather/shutdown."
The "normal" range is from 0 to 33 percent and is used during normal
ground and flight
configurations when the engine is operating. The engine can be
restarted within this range if the
engine control is in the auto mode. An air restart is normally an
automated procedure if the
propeller speed falls below 1,488 rpm and the condition lever is
within the "normal" run range.
The "shut down" range is between 33 and 66 percent. When the lever is
within this range, the
engine fuel valve will close, shutting off fuel to the engine. The
engine cannot be restarted with
the lever in this range. When the PPO is configured for payload
operations, this range locks the
iris for the camera.
The "feather/shutdown" range is between 66 and 100 percent. The
propeller will be feathered when
the lever is within this range.
Warning Signals
There is an audible warning when an engine failure occurs. However,
the same tone is used for
every warning; the sound was not distinctive for a loss of engine
power. The avionics technician
stated that he heard the warning, but thought it was activating
because they lost the Iridium
satellite. In addition to the aural warning, the pilot should have
seen a loss of torque and an
exhaust gas temperature warning on the heads-down display.
Meteorological Information
The weather conditions reported at OLS at 0354 were: Calm wind; 10
statute miles visibility; clear
skies; temperature 10 degrees Celsius; dew point minus 10 degrees
Celsius; altimeter 30.00
inches-of-mercury.
Communications/Air Traffic Control
COA
The COA was issued by the FAA to the Department of Homeland
Security/CBP on March 31, 2006, and was
valid from April 1, 2006, through February 28, 2007. The COA defined
the airspace parameters,
guidelines, and limitations under which BP-101 was allowed to operate
within the NAS.
Between September 2005 and April 2006, the corridor along the southern
border in which the UA was
authorized to operate expanded from 38 to 344 miles. However, LOS
capabilities limited the UA's
operations to only 175 miles of the 344 authorized miles.
Additionally, in April 2006, the COA was
revised to change the operating altitude from 13,000 to 15,000 feet in
order that LOS capabilities
could be maintained.
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The COA authorized daily UA operations from 0000 to 1500 coordinated
universal time, operating at
15,000 feet msl within the authorized altitude block of 14,000 to
16,000 feet msl in the Southern
U.S. Border TFR. The COA in effect at the time of the accident
identified an area of airspace that
was approximately 15 nautical miles wide and 344 miles long
immediately north of the southern U.S.
border for UA operations. Flight Data Center Notice to Airman (FDC
NOTAM) 6/2477 addressed flight
restrictions for other aircraft operating within this TFR airspace.
The COA specified that
takeoffs and landings were to be made from FHU, where the UA would
transit through the restricted
airspace, R2303, until it reached 15,000 feet, at which, it could
transition into the TFR. The COA
stated that the pilot was required to notify ATC when requesting to
move from one area of the TFR
to another.
The COA required that takeoffs and landings be made in VMC and that
the UA be operated in
accordance with IFR within the boundaries of the TFR.
Special provisions set forth in the COA required that the UA have a
means of automatic recovery in
the event of lost link. The intent of this requirement was to make the
UA operations predictable
in the event of lost link.
Air traffic controllers were provided with mandatory training in March
2006 regarding the COA.
This training consisted of a 30-minute briefing and PowerPoint
presentation.
Communications/Radar
The pilot of BP-101 was in contact with the Albuquerque Air Route
Traffic Control Center (ZAB). At
0137, the pilot of BP-101 requested and received clearance to operate
in the TFR as defined in the
COA. At 0339:45, the ZAB Sector 42 controller lost the Mode C
transponder code for BP-101 and
transmitted, "Omaha one zero, radar contact lost, reset transponder."
When this occurred, the ZAB
controller blocked the airspace from 15,000 feet to the surface. At
0340, the UA pilot notified
the ZAB watch desk that the data link had been lost with the UA. At
0340:49, the ZAB controller
transmitted, "Omaha one zero, Albuquerque Center" but did not get a
response. The ZAB controller
then observed that a primary target, which he associated with BP-101,
tracked northeast and turned
to the southeast; then, he lost the primary return. Between 0340 and
0344, the ZAB operations
manager in charge (OMIC) coordinated with the Western Air Defense
Sector (WADS) to solicit WADS
assistance with locating the UA. WADS reported that the last radar
contact it had with the UA was
at 10,400 feet located at 3149.09N/11057.02W. At 0352, Tucson approach
control blocked airspace
15,000 feet and below to protect for the possibility that the UA would
transverse Tucson's
airspace. At 0412, WADS advised the OMIC that they had tracked BP-101
to a point 10 miles
northwest of Nogales, Arizona. At 0447, Tucson approach advised that,
based on recorded radar
replay, the last recorded position it had on BP-101 was about 25 miles
northwest of Nogales,
Arizona. At 0625, CBP notified ZAB that BP-101 had been located on the
ground.
Both the ZAB controller and the OMIC stated that they expected the
BP-101 to fly the same course
that it flew on several other lost-link events, which took it through
a corridor just north of
Nogales, Arizona, at 15,000 feet to a final recovery at FHU. Following
the loss of radar contact
and radio communications, ATC (the ZAB controller) queried the UA
pilot regarding the location of
the UA. According to the controller, the UA pilot did not know the
location of the aircraft.
While ATC considered the loss of radar contact and radio
communications with BP-101 an emergency,
neither the pilot nor ATC declared an emergency.
The COA states:
In the event of Lost Link, the PIC [pilot-in-command] shall
immediately inform ATC of the following:
1. The UAS call sign.
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2. UAS IFF [Identification, Friend or Foe] squawk.
3. Lost link profile.
4. Last known position (as per FAA procedures, position information
will be given relative to
NAVAIDS [navigation aids]).
5. Pre-programmed airspeed.
6. Usable fuel remaining (expressed in hours and minutes).
7. Heading/routing from the last known position to the lost link
emergency mission loiter.
There were no communications between ZAB and the UA pilot regarding a
specific or preferred
lost-link flight profile, as required by the COA.
Following the accident, radar data were provided to CBP from the Air
Marine Operations Center
(AMOC) in Riverside, California. The AMOC reported that the last Mode
C return that it received
was at 0335 at coordinates 31.42 N/111.25 W. AMOC also reported that
the last primary radar
contact was at 0349 at coordinates 31.34 N/110.56 W. Although the AMOC
does not provide ATC
services for the CBP UA, it constantly monitors the UA's position and
status. The radar data
monitored by AMOC is provided by other ATC facilities.
Flight Recorders
The GCS is equipped with recording equipment that stores telemetry in
computer "data logger" files
as well as telemetry information, status messages, and video on
videocassette tapes.
The Safety Board took possession of the tapes that were recorded for
the accident flight. These
tapes recorded the telemetry, status, and video information before,
during, and after the time of
the accident. The Board also acquired copies (on compact disks) of
"data logger" files, which were
recorded during the accident. These disks contained only telemetry
information.
The telemetry from the data logger files was reviewed during a visit
to the GA-ASI facility on May
17-18, 2006. Information retrieved from these files is contained in
the systems group chairman's
factual report. A playback of the videocassette tapes was accomplished
during the same visit. The
data were used to confirm the telemetry recorded on the data logger
files. The data showed:
03:32:57 Control Transfer from PPO-1 to PPO-2 took place
03:32:58 Feather Lever was in the stop position
03:33:01 Engine Out Detected Warning was displayed on the heads down
display
03:33:15 Lost Payload Video
03:33:48 Speed Priority Warning and Pitch Up Then Down
03:34:11 UA Entered a Left Turn
03:35:03 Lost All Telemetry and video Data
The replay of the recorded information also revealed that the pilot
who performed the mission setup
for the flight (not the accident pilot) programmed an initial
lost-link altitude of 9,000 feet and
an initial lost-link heading of 260 degrees.
Wreckage and Impact Information
The UA impacted the terrain in a sparsely populated desert area. The
geographic coordinates at the
accident site were: 31 degrees, 34.002 minutes north latitude; 110
degrees, 56.473 minutes west
longitude. The terrain elevation at the accident site was
approximately 3,803 feet above msl.
The wreckage path was located on the upslope of rapidly rising, rocky
desert terrain. The slope of
the terrain was approximately 45 degrees. Just before the initial
terrain impact were several
small scrub trees, which contained broken limbs. The angle of the
breaks was consistent with a
near wings level, relatively flat angle of impact. The wreckage path
was oriented upward along the
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CHI06MA121
rising terrain, on a heading of approximately 100 degrees, with the
main wreckage coming to rest on
a heading of 90 degrees.
The initial ground impact was near the base of the rising terrain. The
UA's vertical fin was
separated from the empennage and was located near the base of the
slope. The main portion of the
fuselage, the wings, and the empennage were located along the
up-sloping terrain near the crest of
the slope. Portions of the forward fuselage, avionics equipment, and
ballast from the forward
fuselage bay were located above the crest of the rising terrain. The
entire wreckage path was
approximately 95 feet long.
The forward section of the fuselage was separated from the rear
section near the forward fuel tank.
All of the fuselage fuel bladders were ruptured, and the odor of jet
aviation fuel was present.
The avionics bay had separated from the forward fuselage. The fuselage
from the aft fuel tank
rearward was damaged but primarily intact. The V-tail elevator
surfaces remained attached to the
empennage, and they were not damaged. The ventral fin and rudder were
separated from the empennage
and from each other and were found near the bottom of the rising
terrain.
The inboard sections of the left and right wings were located with the
main fuselage. A 7-foot
section of the outboard portion of the left wing was located in the
trees about 25 feet from the
debris field at the base of the rising terrain. The left wing's
leading edge was damaged, and the
forward spar was separated from the skin. The left inboard and
outboard flaps, along with the left
inboard aileron, remained attached to the portion of the wing that was
attached to the fuselage.
The left wing outboard aileron remained attached to the separated
outboard section of the left wing.
The inboard section of the right wing, which remained attached to the
fuselage, exhibited
leading-edge deformation, rearward crushing, and bending. The outboard
14 feet of the right wing
was detached from the inboard section of the wing and found near the
propeller. The right inboard
flap was separated from the wing, and the right outboard flap remained
attached. The ailerons
remained attached to the separated outboard section of the wing.
The left main landing gear was relatively intact and was found in the
extended position. The upper
portion of the right main landing gear strut remained attached to the
fuselage. The lower portion
of the right main landing gear strut and the tire were separated from
the upper portion of the
strut. The upper portion of the strut was extended from the fuselage.
The nose landing gear
separated from the fuselage in two pieces, and both were located near
the main wreckage.
The engine bay portion of the aft fuselage was largely intact. The
upper and lower engine access
panels remained attached to the fuselage. The signal from the
emergency locator transmitter (ELT)
was not detected during the search operations for the UA. Examination
of the ELT revealed that the
antenna cable was separated from the transmitter. The ELT was sent to
its manufacturer for
operational testing. The test results showed normal operation of the
ELT.
The propeller remained attached to the engine. As part of the
investigation, the blades were
arbitrarily marked A, B, and C. The A blade came to rest in the 12
o'clock position, blade B was
at the 4 o'clock position, and the blade C was at the 8 o'clock
position. Both the B and C blades
came to rest on an outcropping of rocks and boulders. The A blade
exhibited leading-edge nicks,
chordwise scratches, and gouges on its face. This blade was bent
toward its face and was loose in
the hub. The B blade exhibited gouges on its outboard face and was
bent toward the back of the
blade. The C blade exhibited gouges on its back, and it was bent
toward the face of the blade.
The propeller spinner exhibited localized crushing on its sides.
Localized areas of rotational
scarring were present on the sides of the spinner.
The UA was powered by a Honeywell TPE 331-10Y engine, serial number
P121015C. On-scene inspection
of the engine revealed the propeller pitch control setting was 89
degrees, the power lever angle
setting was 90 degrees, the underspeed governor setting was 32
degrees, and the hour meter for the
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engine read 498 hours. All of the engine control cables were connected
to their respective servos.
The engine controls moved when the servos were manipulated by hand.
Engine control continuity was
established to the servos. No fuel or oil leaks were noted in the
engine bay nor was any debris
noted in the inlet assembly ducting. Fluids consistent with engine oil
and jet fuel were found in
their respective hoses. Debris was found in the starter/generator
cooling duct. The
starter/generator rotated freely when its fan was turned by hand. The
left side igniter had an
area of white discoloration. The top igniter's tip contained debris
deposits. Mechanical
continuity of the engine was observed with the rotation of the
impeller, turbine rotor, and
propeller shaft. The drive-train connectivity to the oil scavenge pump
and to the fuel pump drive
shaft was observed in the scavenge port.
The engine was shipped to Honeywell for further examination, which was
accomplished on June 15,
2006. The fuel cutoff valve cover sustained impact damage. A liquid
consistent with jet fuel was
present at the fuel pump inlet and exited the fitting when the engine
was rotated opposite the
normal direction of rotation. The impeller was rotated, and resistance
to its rotation was
observed. The resistance increased when the engine was placed in a
nose-down attitude.
Examination of the gearbox found no anomalies. A borescope examination
of the power section
revealed no damage to the fuel nozzles. The first- and second-stage
compressors exhibited no
damage or rub marks. Examination of the first-stage turbine nozzle and
the third-stage turbine
revealed no damage. No anomalies were noted during the engine
examination.
The starter/generator was an engine accessory pad that was a driven,
air-cooled, brush-type unit.
The starter/generator and the generator control unit (GCU) were tested
at the manufacturer's
facility and found to be operational.
Tests and Research
Lockups
A lockup is any malfunction that causes the GCS PPO screens to stop
updating and to "freeze." A
review of the lockup events for BP-101 revealed that two lockups
occurred just before the launch of
the accident flight. A GA-ASI avionics technician stated that the
maintenance action to correct
the lockup was to switch the main processor circuit cards between
PPO-1 and PPO-2. This action
appeared to correct the problem, and the UA was able to depart.
A log that was kept in the GCS indicated that there had been 16
lockups involving BP-101 for
various reasons since December 12, 2005. These lockups occurred on
both PPO-1 and PPO-2. The log
did not provide any supporting data explaining the reason for the
lockups.
On May 15-16, 2006, testing was performed on the GCS in an attempt to
duplicate the lockups by
either simulating an aircraft flight or exercising the suspect circuit
boards using debug software.
All of the tests performed failed to duplicate the lockups.
Emergency Procedures
The emergency procedures for a rack switch and reboot, as found in the
checklist located within the
GCS state:
On rack taking control, verify all presets, hold modes, and control
commands are the same as the
current rack.
1. SAS [Stability Augmentation System] - On
2. IGNITION - HOT
3. STOP & FEATHER - Match Receiving PSO [Pilot/Sensor Operator]
4. SPEED LEVER - Match Receiving PSO
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CHI06MA121
5. POWER LEVER - Match Receiving PSO
Verify all presets, hold modes, and control commands are the same.
With pilots in both seats (be prepared to switch back)
Additional Information
The UAS program began in August 2005 when the U.S. Border Patrol
granted a contract to GA-ASI to
develop the program. At the end of September 2005, BP-101 was flown to
FHU, and its first flight
was made operating within R2303. On October 1, 2005, the Office of Air
and Marine, Customs and
Border Protection, was formed. This office then became responsible for
the operation of the UAS
program. On October 4, 2005, BP-101 started flying missions.
Parties to the investigation were the FAA, CBP, GA-ASI, and Honeywell.
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Landing Facility/Approach Information
Airport Name
Runway Surface Type:
Runway Surface Condition:
Airport ID:
Type Instrument Approach:
VFR Approach/Landing:
Aircraft Information
Aircraft Manufacturer
Airworthiness Certificate(s):
Landing Gear Type:
Homebuilt Aircraft? Number of Seats:
Engine Type:
- Aircraft Inspection Information
Type of Last Inspection
- Emergency Locator Transmitter (ELT) Information
ELT Installed? ELT Operated?
Owner/Operator Information
Registered Aircraft Owner
Operator of Aircraft
Operator Does Business As:
- Type of U.S. Certificate(s) Held:
Air Carrier Operating Certificate(s):
Operating Certificate:
Regulation Flight Conducted Under:
Type of Flight Operation Conducted:
Operator Certificate:
Operator Designator Code:
Street Address
City
Street Address
City
ELT Aided in Locating Accident Site?
Time Since Last Inspection
Hours
Model/Series: Engine Manufacturer:
Date of Last Inspection
Model/Series
Certified Max Gross Wt. Number of Engines: LBS
Serial Number
Airport Elevation
Ft. MSL
Runway Used Runway Length Runway Width
Rated Power:
Airframe Total Time
Hours
State Zip Code
State Zip Code
No No Yes
Retractable - Tricycle
Aerial Observation
Public Use
None
Same as Reg'd Aircraft Owner
Same as Reg'd Aircraft Owner
DC Washington
1300 Pennsylvania Ave. NW
U.S. Customs and Border Protection
966
940 HP TPE-331 Honeywell Turbo Prop
1 10500 0 No
BP101 Predator B General Atomics
Forced Landing
Accident
04/25/2006
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First Pilot Information
Name
Sex: Seat Occupied:
City
Principal Profession: Certificate Number:
State Date of Birth Age
Certificate(s):
Airplane Rating(s):
Rotorcraft/Glider/LTA:
Instrument Rating(s):
Instructor Rating(s):
Type Rating/Endorsement for Accident/Incident Aircraft? Current
Biennial Flight Review?
Medical Cert. Status:
- Flight Time Matrix
Medical Cert.: Date of Last Medical Exam:
Glider
Lighter
Than Air
Rotorcraft
Instrument
Actual Simulated
Airplane
Mult-Engine
Night
Airplane
Single Engine
This Make
and Model
All A/C
Total Time
Pilot In Command(PIC)
Instructor
Last 90 Days
Last 30 Days
Last 24 Hours
Seatbelt Used? Shoulder Harness Used? Toxicology Performed? Second
Pilot?
Departure Time Time Zone State Airport Identifier
State Airport Identifier
Type of Flight Plan Filed:
Departure Point
Destination
Flight Plan/Itinerary
Type of Clearance:
Type of Airspace:
Weather Information
Source of Briefing:
Method of Briefing:
IFR
MST 1851
HFU AZ
Local Flight
Sierra Vista
IFR
No No
0 0 27 27
25 800 0 825
1000 1000 27 2545
650 1400 1200 27 3571
05/2005 Without Waivers/Limitations Class 1
02/2006
Airplane Multi-engine; Airplane Single-engine; Instrument Airplane
Flight Instructor; Commercial
Airplane
Multi-engine Land; Single-engine Land
None
On File Occupational Pilot M
35 On File On File On File On File
Accident
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Weather Information
WOF ID Observation Time
Sky/Lowest Cloud Condition:
Time Zone WOF Elevation
Ft. MSL
WOF Distance From Accident Site
NM
Ft. AGL Condition of Light:
Direction From Accident Site
Deg. Mag.
Altimeter: "Hg
Density Altitude: Ft.
Visibility: SM
Wind Direction:
Ft. AGL
Weather Condtions at Accident Site:
°C °C Dew Point:
Gusts:
Lowest Ceiling:
Temperature:
Wind Speed:
Visibility (RVR): Ft.
Restrictions to Visibility:
Type of Precipitation:
Accident Information
Aircraft Damage:
Visibility (RVV) SM
Aircraft Fire:
Intensity of Precipitation:
Aircraft Explosion
Classification:
- Injury Summary Matrix
First Pilot
Second Pilot
Student Pilot
Check Pilot
Flight Engineer
Cabin Attendants
Other Crew
Passengers
- TOTAL ABOARD -
Other Ground
- GRAND TOTAL -
Fatal Serious Minor None TOTAL
Flight Instructor
1 1
1 1
1 1
None None Substantial
No Obscuration; No Precipitation
Visual Conditions
-10 10
30.00 10 None
Night Clear
140 10 3955 PST 0354 OLS
Accident
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Administrative Information
Investigator-In-Charge (IIC)
Additional Persons Participating in This Accident/Incident
Investigation:
David Keenan
AAI-100
Pamela S. Sullivan
Accident
04/25/2006
CHI06MA121
Will the "pilots" of this UAV face FAA Enforcement Action?
How do UAV pilots "see-and-avoid" during night operations?
Crash highlights risks of uncrewed aircraft
31 October 2007
NewScientist.com news service
A mix-up between fuel and camera controls caused a 4.5-tonne
uncrewed aircraft to smash into a residential area near the town
of Nogales, Arizona. No one was hurt but the incident raises
serious questions about the safety of flying uncrewed aerial
vehicles (UAVs) in civilian airspace and could hamper plans to use
them more widely.
On 25 April 2006, a Predator B surveillance UAV belonging to US
Customs and Border Protection (CBP) was patrolling the Mexican
border when the ground pilot's radio-control console froze,
prompting him to switch to a back-up. Last week the US National
Transportation Safety Board released a damning report into how the
change caused the plane to crash.
The lever controlling fuel supply on the first console was set up
to control the video camera on the second. When the pilot switched
consoles, he failed to notice the difference, which caused the
engine to cut out. The report slammed the CBP for differences on
the consoles, poor pilot training, the failure to use a checklist
when switching consoles, and the lack of a back-up pilot.
Some aerospace firms hope to sell UAVs (currently used mainly by
the military) for monitoring floods, surveillance and firefighting
(New Scientist, 1 December 2006, p 26). The report highlights why
this might be a bad idea. It will also make commercial success
harder to pull off. There could be an expensive regulatory
backlash, says Bruno Esposito of the European UAV Working Group.
"I hope this will not lead to a requirement for very expensive
ground control avionics. That will kill this market."
http://www.ntsb.gov/ntsb/GenPDF.asp?id=CHI06MA121&rpt=fa
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Investigated By:
Location/Time
State Zip Code Local Time Time Zone
Model/Series Aircraft Manufacturer
Aircraft Information Summary
Sightseeing Flight: Air Medical Transport Flight:
Narrative
Brief narrative statement of facts, conditions and circumstances
pertinent to the accident/incident:
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Nearest City/Place
Direction From Airport: Distance From Landing Facility: Airport
Proximity:
Type of Aircraft
Aircraft Registration Number:
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History of Flight
On April 25, 2006, about 0350 mountain standard time, a MQ-9 (Predator
B) aircraft, serial number
BP-101, call sign OHAMA 10, collided with the terrain approximately 10
nautical miles northwest of
the Nogales International Airport (OLS), Nogales, Arizona. The
unmanned aircraft system (UAS) was
owned by U.S. Customs and Border Protection (CBP) and operated as a
public-use aircraft. The
flight was operating in night visual meteorological conditions (VMC).
An instrument flight rules
(IFR) flight plan had been filed and activated for the flight. The
unmanned aircraft (UA)
sustained substantial damage. There were no injuries to persons on the
ground. The flight
originated from the Libby Army Airfield (FHU), Sierra Vista, Arizona,
at 1851, on April 24, 2006.
The wreckage was located at 0630.
The flight was being flown from a ground control station (GCS) located
at FHU. The GCS contains
two nearly identical pilot payload operator (PPO) consoles, PPO-1 and
PPO-2. Normally, a certified
pilot controls the UA from PPO-1, and the camera payload operator
(typically a U.S. Border Patrol
agent) controls the camera, which is mounted on the UA, from PPO-2.
Although the aircraft control
levers (flaps, condition lever, throttle, and speed lever) on PPO-1
and PPO-2 appear identical,
they may have different functions depending on which console controls
the UA. When PPO-1 controls
the UA, movement the condition lever to the forward position opens the
fuel valve to the engine;
movement to the middle position closes the fuel valve to the engine,
which shuts down the engine;
and movement to the aft position causes the propeller to feather. When
the UA is controlled by
PPO-1, the condition lever at the PPO-2 console controls the camera's
iris setting. Moving the
lever forward increases the iris opening, moving the lever to the
middle position locks the
camera's iris setting, and moving the lever aft decreases the opening.
Typically, the lever is set
in the middle position.
In addition to the pilot and payload operator, other personnel present
in the GCS were an avionics
technician and a sensor operator, both of whom are General Atomics
Aeronautical Systems, Inc.
(GA-ASI) employees. GA-ASI manufactures the Predator B and was
contracted by CBP to fly and
maintain BP-101.
The flight was originally scheduled to take off at 1700 but was
delayed because of the inability to
establish a communication link between the UA and PPO-1 during initial
power up. The avionics
technician stated he powered down the UA and downloaded the system
status. He then recycled the
power on PPO-1 and PPO-2, but again he was not able to establish an
uplink on PPO-1. The
technician did not attempt to gain an uplink on PPO-2 during either of
these power-ups. The
technician reported that he again captured the system status data on
his laptop and called his
supervisor at the manufacturer's facility in California for
assistance. He reported that his
supervisor and the technical support personnel with whom he spoke had
not seen this type of problem
before. They recommended that he switch the main processor cards
between PPO-1 and PPO-2. The
No No
Airplane Predator B General Atomics
Off Airport/Airstrip
MST 0350 85621 AZ Nogales
NTSB Accident
None 04/25/2006
None CHI06MA121
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technician stated that he did this, powered up the system, and was
able to establish an uplink on
both PPO-1 and PPO-2. He stated that everything operated normally at
this point, and he went off
duty at 2000.
Because the UA typically stays airborne for extended periods of time,
more than one pilot is
scheduled to fly during each mission. The pilots rotate flying duties
every couple of hours
throughout the duration of the flight. The pilot who was flying the
initial part of the accident
flight, including the takeoff, was not the accident pilot. The
accident pilot reported that he was
scheduled to work from 1900 on April 24, 2006, until 0500 on the day
of the accident. The accident
pilot reported that he took control of the flight at 1900 when BP-101
was already airborne and
operating in the temporary flight restriction (TFR) airspace. He
reported that he flew from 1900
until 2100. At 2100, another pilot resumed control of the flight. The
accident pilot took control
of the flight again at 0300 and was scheduled to fly until 0500. He
stated that the change-over
briefing at 0300 was normal and that nothing had changed with the
flight.
He reported that, shortly after he resumed control of the flight, the
lower monitor screen went
blank on PPO-1. The screen then reappeared, but the telemetry
(transmitted data) was locked up, so
he decided to switch control of the UA to PPO-2. The pilot stated that
he informed the Border
Patrol agent who was at PPO-2 that he needed to switch positions. The
Border Patrol agent stated
that he moved away from PPO-2 and left the GCS. The pilot stated that
he verified the ignition was
"hot" on PPO-2 and that the stability augmentation system was on. He
reported that, at some point,
he used his cell phone to call another pilot (who had been his
instructor) to discuss what was
going on. At the time, the instructor was in a hangar building across
the ramp.
Checklist procedures state that there should be pilots in both the
PPO-1 and PPO-2 seats before
switching control of the UA from one PPO to the other. CBP stated that
its procedures call for the
avionics technician to assume the duties of a co-pilot for the purpose
of assisting with the
checklist items before switching control from one PPO to the other.
This did not occur during the
accident sequence.
The pilot stated that he did not use the checklist when making the
switch. Checklist procedures
state that before switching operational control between the two
consoles, the pilot must match the
control positions on the new console to those on the console that had
been controlling the UA. The
pilot stated in an interview that he was in a "hurry" and that he
failed to do this. The condition
lever on PPO-2 was in the fuel cutoff position when the switch from
PPO-1 to PPO-2 occurred. As a
result, the fuel was cut off to the UA engine when control was
transferred to PPO-2.
The pilot stated that, after the switch to the PPO-2 console, he
noticed that the UA was not
maintaining altitude, but he did not know why. He decided to shut down
the ground data terminal
(GDT) so that the UA would begin its lost-link procedure. This
procedure called for the UA to
autonomously climb to 15,000 feet above mean sea level (msl) and fly a
predetermined course until
contact could be reestablished. With no engine power, the UA continued
to descend below
line-of-sight (LOS) communications, and further attempts to
reestablish contact with the UA were
not successful.
The pilot reported that the instructor pilot entered the GCS shortly
after the avionics technician
turned off the GDT. He informed the instructor of what occurred, and
the instructor looked at the
controls and stated that the controls were not positioned correctly.
The instructor tried to
reestablish contact with BP-101 in both the GCS and the mobile GCS
(MGCS); however, BP-101 had
already descended below LOS, and contact could not be reestablished.
The avionics technician who was positioned at the multifunction
workstation (MFW) in the rear of
the GCS recalled the events, as follows. He stated that he heard the
pilot say that PPO-1 had
locked up. He then noticed that the chart display on his monitor had
locked up. The technician
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stated that he walked up to the front of the GCS and looked at the
status-warning screen on PPO-2,
which indicated that PPO-1 was locked up. He advised the pilot that
they needed to switch control
to PPO-2. He then went back to the MFW to open up another program,
which showed him what processes
were running on PPO-1 so that he could record this information. The
technician then returned to
the front of the GCS, at which time the pilot was using his cell phone
to call for support. He
advised the pilot again that they needed to switch control from PPO-1
to PPO-2. The technician
stated that the pilot switched control to PPO-2 and that the pilot
then stated that PPO-2 was also
locked up. He then told the pilot that they needed to send the UA into
its lost-link procedure by
shutting off the GDT. The technician stated that he pulled the plug to
the PPO-1 processor rack
then switched off the circuit breaker to the GDT. He told the pilot
that they needed to go into
the MGCS to try and recover the UA because the MGCS was up and running
for the entire flight. He
stated that he went into the MGCS to make sure that it was ready for
the pilot, and, when he
returned to the GCS, the other pilot was already there. He stated that
he continued to work with
the pilots to try and establish link with the UA.
Personnel information
The pilot, age 35, was employed by GA-ASI. The pilot held a commercial
pilot certificate, with
single-engine land, multi-engine land, and instrument ratings. He also
held a certified flight
instructor certificate with single-engine land, multi-engine land, and
instrument ratings, along
with an advanced ground instructor certificate. The pilot's most
recent Federal Aviation
Administration (FAA) first-class medical certificate was issued on May
31, 2005. The medical
certificate did not contain any limitations.
The pilot reported that he had 3,571 total flight hours, which
included 519 hours of Predator A
flight time and 27 hours of Predator B hours. The 27 hours of Predator
B time were flown
throughout 9 flights, 5 hours of which were training flights. The 5
hours of training were
conducted at the GA-ASI facility in Palmdale, California. There were
no Predator B simulators
available before the accident, so all of the flight training was
accomplished with the actual UAS.
At the time of the accident, CBP flight time requirements were 200
hours manned aircraft time and
200 hours UAS flight time. The UAS time was not required to be type
specific.
CBP required that "All operators shall also be certified by the
contractor as being fully capable
of maintaining and operating the 'Predator B' UA and its associated
equipment." GA-ASI used a
training syllabus, which had been approved by the Air Force, to train
pilots to operate the CBP UAS
for the Air Force. Once a pilot completed the training syllabus,
GA-ASI would present the
completed training records, which had been approved by the Air Force
Government Flight
Representative (GFR), to CBP. CBP would then either approve or
disapprove the specific pilot to
operate the CBP UAS. At the time of the accident, CBP did not have a
fully trained GFR on its
staff.
The pilot's training was documented on several different Department of
Defense and Air Force forms.
DD Form 2627 indicated that on February 17, 2006, the Air Force GFR
approved the pilot to begin
MQ-9 training. AFMC Form 68 MQ-9 Pilot Conversion indicated the pilot
completed the training on
March 24, 2006. On May 5, 2006, which was after the date of this
accident, the Air Force GFR
disapproved the pilot's request for approval to act as a MQ-9 pilot
and cited that the pilot had
not completed some training modules.
Five of the training events listed on the AFMC Form 68 MQ-9 Pilot
Conversion form were not
accomplished during the pilot's training. Those events were: Mission
Planning/Briefing/Debriefing, Handover Procedures - Ground, Mission
Monitor/MFW Procedures,
Operational Mission Procedures, and Handover Procedures - Airborne.
The training syllabus states
that Air Force grading criteria are used to evaluate the pilot's
performance during training.
According to CBP, GA-ASI contacted their person who was being trained
as a GFR and requested that
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the accident pilot be added to CBP's approved pilot list before the
Air Force GFR approval. CBP
stated that their GFR trainee gave GA-ASI a verbal approval so that
the pilot could operate the CBP
UAS but only when an instructor pilot was physically present in the
GCS. This verbal approval was
not standard practice for CBP.
Nowhere in the training records provided to the Safety Board does it
list specific training on
procedures to switch control of the UAS from one PPO to the other. As
previously stated, the
majority of the pilot's UAS experience was with the Predator A. The
Predator B has different and a
more complex engine and engine controls than the Predator A. Also, the
control console for the
Predator A does not have a condition lever that needs to be matched up
between the PPOs when
switching from one PPO to the other.
Aircraft Information
The UA was a MQ-9 (Predator B) aircraft, serial number BP-101,
manufactured by GA-ASI. The
accident occurred on the UA's 118th flight. The UA typically flew
14-hour missions, 4 days per
week, and a shorter mission on the 5th day. According to the flight
record, the engine and
airframe had accumulated a total of 498 and 1,217 hours, respectively.
The Predator B is approximately 36 feet in length with a wingspan of
66 feet. The maximum gross
weight is 10,000 pounds. The UA can stay airborne for more than 30
hours at altitudes up to 50,000
feet. The fuselage is a composite structure of impregnated graphite
skin and Nomex honeycomb
stiffening panels. The fuselage incorporated an avionics bay, fuel
bays, an accessory bay, landing
gear bays, and an engine bay.
The fuel tank bays consisted of three inline bladder fuel tanks
located in the forward, header, and
aft fuel tank bays. Each wing also contained an inboard and an
outboard fuel tank. The aircraft
total fuel capacity was 3,920 pounds.
The UA was powered by a Honeywell TPE 331-10Y turboprop engine. The
engine is mounted at the rear
of the fuselage and produces 900-shaft horsepower. The engine controls
and indicators located in
the GCS were similar to the engine controls for a manned aircraft. The
engine was equipped with an
in-flight restart capability.
A three-bladed, variable pitch McCauley 36FR36C606-B propeller was
installed on the aircraft. The
pusher propeller was full-feathering and capable of reverse pitch.
The most recent maintenance performed on BP-101 was a 200-hour
inspection that was performed on
April 21, 2006. Interviews with GA-ASI and CBP personnel revealed
that, due to limited funding,
there was virtually no stock of spare parts at FHU for the BP-101.
They stated that, when they
needed a part, they would have to wait for it to be shipped from the
manufacturer.
At the time of the accident, CBP was unable to certify to the FAA that
BP-101 was airworthy.
Because of national security issues and past experience with similar
UASs, the FAA temporarily
waived this requirement for the issuance of the Certificate of Waiver
or Authorization (COA) to
operate in the National Airspace System (NAS).
UA Control System
The accident UA was operated by means of C-band (signal
communications), which provided for LOS
control. The UA descended below LOS after the engine stopped producing
power.
A secondary means of control was provided through the Iridium
satellite communication system.
However, in the Iridium control mode, there is limited ability to
control the UA; under Iridium
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control, the only way to control the UA is by using autopilot hold
modes. All hold modes
(altitude, airspeed, and heading) must be active for the Iridium
satellite to control of the UA.
The hold modes were on before the lost link. If both the Iridium and
LOS uplinks are active, the
LOS link has priority, and the Iridium data is ignored. However, when
the fuel was cut off to the
engine and the UA began shedding electrical equipment to conserve
battery power, the Iridium system
was one of the items that was shed. The UA is also equipped with an
auto-ignition system, but this
system will not work unless the Iridium system is operable.
Lost Link
A lost data link occurs when the UA is no longer receiving
command/control data from the GCS. In
the event of a lost data link between the GCS and UA, the UA will
enter a flightpath known as the
lost-link profile, which is predetermined and performed autonomously,
until the GCS operation can
be restored and a data link can be reestablished. The lost-link
profile, including the initial
lost-link heading and altitude, is uploaded to the UA before every
mission
Following the accident, it was determined that there were three
lost-link profiles stored on the
computer in the GCS; only one of which could be active at any given
time. The area in which the UA
was operating would dictate which profile would be uploaded. The pilot
can change any or all of
this information during the flight. One of the pilots stated that,
during the flight, he moved the
first waypoint in the profile to coincide with the second waypoint. It
was not unusual for the
pilots to move the first waypoint, depending on the location of the
UA.
On occasions other than the accident, when the UA goes into a
lost-link profile, it will initially
turn to a preset lost-link heading, go to full power, and climb for 51
seconds at a commanded
airspeed of 105 knots. If the UA is within 200 feet of the lost-link
altitude (or higher), this
first step is skipped. In the next step, the system generates a
waypoint at the preset lost-link
altitude, 2.5 nautical miles from the location where the UA started
the lost-link profile, in the
direction of the lost-link heading, and the UA proceeds to that
waypoint. Once the UA reaches that
waypoint and the lost-link altitude (or 30 minutes later, whichever
comes first), it will proceed
to fly the remainder of the lost-link profile. This portion of the
lost-link profile consists of a
predetermined series of altitudes and locations, which form a path
that the UA will autonomously
fly. If a data link cannot be reestablished, the UA cannot land, and
it will eventually run out of
fuel and crash at some location along the lost-link profile route.
Another contractor, Organizational Strategies, Inc. (OSI), provided
the coordinates for the
lost-link waypoints to CBP. OSI reported that it developed the
waypoints using an Internet
satellite website. CBP reported that it also used the same Internet
satellite website to verify
the location of the waypoints. According to this website, some of the
website's imagery is 1 to 3
years old. Neither OSI nor CBP used additional methods to confirm that
the waypoints were not
located over populated areas.
The COA lists the following lost-link procedures:
1. Turn northward toward and proceed within the TFR to the appropriate
Lost Link Location.
2. Hold for 30 minutes.
CBP shall ensure that the UAS remains at the last assigned altitude
and within the TFR at
all times, including while holding.
3. Proceed within the TFR to the adjacent Lost Link Location in the
direction of Libby AAF
[Army Airfield] (and hold as indicated in step 2). Procedure steps 2 &
3 shall be repeated until
the UAS has entered R2303 [restricted airspace].
4. Depending on the status of R2303, the UAS shall:
a. Hold at the Lost Link Location in Area 2 until R2303 becomes
active, or
b. Enter R2303, and
Then cancel IFR services with ATC [air traffic control] and proceed to
Libby AAF, in
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accordance with the appropriate Certificate of Authorization.
Engine Controls
The condition lever, which is installed in both the PPO-1 and PPO-2
consoles, serves a different
function depending on whether the station is being used by the payload
operator or by the pilot.
In the payload operator configuration, the lever is used to control
the iris of the camera. Moving
the lever forward increases the iris opening, moving the lever to the
middle position locks the
camera's iris setting, and moving the lever aft decreases the opening.
In the pilot configuration, the lever is used to control the engine
fuel valve and the propeller
feather servo. When in the pilot configuration, the lever has a linear
analog range from 0 to 100
percent, which is divided into thirds: "normal," "shutdown," and
"feather/shutdown."
The "normal" range is from 0 to 33 percent and is used during normal
ground and flight
configurations when the engine is operating. The engine can be
restarted within this range if the
engine control is in the auto mode. An air restart is normally an
automated procedure if the
propeller speed falls below 1,488 rpm and the condition lever is
within the "normal" run range.
The "shut down" range is between 33 and 66 percent. When the lever is
within this range, the
engine fuel valve will close, shutting off fuel to the engine. The
engine cannot be restarted with
the lever in this range. When the PPO is configured for payload
operations, this range locks the
iris for the camera.
The "feather/shutdown" range is between 66 and 100 percent. The
propeller will be feathered when
the lever is within this range.
Warning Signals
There is an audible warning when an engine failure occurs. However,
the same tone is used for
every warning; the sound was not distinctive for a loss of engine
power. The avionics technician
stated that he heard the warning, but thought it was activating
because they lost the Iridium
satellite. In addition to the aural warning, the pilot should have
seen a loss of torque and an
exhaust gas temperature warning on the heads-down display.
Meteorological Information
The weather conditions reported at OLS at 0354 were: Calm wind; 10
statute miles visibility; clear
skies; temperature 10 degrees Celsius; dew point minus 10 degrees
Celsius; altimeter 30.00
inches-of-mercury.
Communications/Air Traffic Control
COA
The COA was issued by the FAA to the Department of Homeland
Security/CBP on March 31, 2006, and was
valid from April 1, 2006, through February 28, 2007. The COA defined
the airspace parameters,
guidelines, and limitations under which BP-101 was allowed to operate
within the NAS.
Between September 2005 and April 2006, the corridor along the southern
border in which the UA was
authorized to operate expanded from 38 to 344 miles. However, LOS
capabilities limited the UA's
operations to only 175 miles of the 344 authorized miles.
Additionally, in April 2006, the COA was
revised to change the operating altitude from 13,000 to 15,000 feet in
order that LOS capabilities
could be maintained.
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The COA authorized daily UA operations from 0000 to 1500 coordinated
universal time, operating at
15,000 feet msl within the authorized altitude block of 14,000 to
16,000 feet msl in the Southern
U.S. Border TFR. The COA in effect at the time of the accident
identified an area of airspace that
was approximately 15 nautical miles wide and 344 miles long
immediately north of the southern U.S.
border for UA operations. Flight Data Center Notice to Airman (FDC
NOTAM) 6/2477 addressed flight
restrictions for other aircraft operating within this TFR airspace.
The COA specified that
takeoffs and landings were to be made from FHU, where the UA would
transit through the restricted
airspace, R2303, until it reached 15,000 feet, at which, it could
transition into the TFR. The COA
stated that the pilot was required to notify ATC when requesting to
move from one area of the TFR
to another.
The COA required that takeoffs and landings be made in VMC and that
the UA be operated in
accordance with IFR within the boundaries of the TFR.
Special provisions set forth in the COA required that the UA have a
means of automatic recovery in
the event of lost link. The intent of this requirement was to make the
UA operations predictable
in the event of lost link.
Air traffic controllers were provided with mandatory training in March
2006 regarding the COA.
This training consisted of a 30-minute briefing and PowerPoint
presentation.
Communications/Radar
The pilot of BP-101 was in contact with the Albuquerque Air Route
Traffic Control Center (ZAB). At
0137, the pilot of BP-101 requested and received clearance to operate
in the TFR as defined in the
COA. At 0339:45, the ZAB Sector 42 controller lost the Mode C
transponder code for BP-101 and
transmitted, "Omaha one zero, radar contact lost, reset transponder."
When this occurred, the ZAB
controller blocked the airspace from 15,000 feet to the surface. At
0340, the UA pilot notified
the ZAB watch desk that the data link had been lost with the UA. At
0340:49, the ZAB controller
transmitted, "Omaha one zero, Albuquerque Center" but did not get a
response. The ZAB controller
then observed that a primary target, which he associated with BP-101,
tracked northeast and turned
to the southeast; then, he lost the primary return. Between 0340 and
0344, the ZAB operations
manager in charge (OMIC) coordinated with the Western Air Defense
Sector (WADS) to solicit WADS
assistance with locating the UA. WADS reported that the last radar
contact it had with the UA was
at 10,400 feet located at 3149.09N/11057.02W. At 0352, Tucson approach
control blocked airspace
15,000 feet and below to protect for the possibility that the UA would
transverse Tucson's
airspace. At 0412, WADS advised the OMIC that they had tracked BP-101
to a point 10 miles
northwest of Nogales, Arizona. At 0447, Tucson approach advised that,
based on recorded radar
replay, the last recorded position it had on BP-101 was about 25 miles
northwest of Nogales,
Arizona. At 0625, CBP notified ZAB that BP-101 had been located on the
ground.
Both the ZAB controller and the OMIC stated that they expected the
BP-101 to fly the same course
that it flew on several other lost-link events, which took it through
a corridor just north of
Nogales, Arizona, at 15,000 feet to a final recovery at FHU. Following
the loss of radar contact
and radio communications, ATC (the ZAB controller) queried the UA
pilot regarding the location of
the UA. According to the controller, the UA pilot did not know the
location of the aircraft.
While ATC considered the loss of radar contact and radio
communications with BP-101 an emergency,
neither the pilot nor ATC declared an emergency.
The COA states:
In the event of Lost Link, the PIC [pilot-in-command] shall
immediately inform ATC of the following:
1. The UAS call sign.
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2. UAS IFF [Identification, Friend or Foe] squawk.
3. Lost link profile.
4. Last known position (as per FAA procedures, position information
will be given relative to
NAVAIDS [navigation aids]).
5. Pre-programmed airspeed.
6. Usable fuel remaining (expressed in hours and minutes).
7. Heading/routing from the last known position to the lost link
emergency mission loiter.
There were no communications between ZAB and the UA pilot regarding a
specific or preferred
lost-link flight profile, as required by the COA.
Following the accident, radar data were provided to CBP from the Air
Marine Operations Center
(AMOC) in Riverside, California. The AMOC reported that the last Mode
C return that it received
was at 0335 at coordinates 31.42 N/111.25 W. AMOC also reported that
the last primary radar
contact was at 0349 at coordinates 31.34 N/110.56 W. Although the AMOC
does not provide ATC
services for the CBP UA, it constantly monitors the UA's position and
status. The radar data
monitored by AMOC is provided by other ATC facilities.
Flight Recorders
The GCS is equipped with recording equipment that stores telemetry in
computer "data logger" files
as well as telemetry information, status messages, and video on
videocassette tapes.
The Safety Board took possession of the tapes that were recorded for
the accident flight. These
tapes recorded the telemetry, status, and video information before,
during, and after the time of
the accident. The Board also acquired copies (on compact disks) of
"data logger" files, which were
recorded during the accident. These disks contained only telemetry
information.
The telemetry from the data logger files was reviewed during a visit
to the GA-ASI facility on May
17-18, 2006. Information retrieved from these files is contained in
the systems group chairman's
factual report. A playback of the videocassette tapes was accomplished
during the same visit. The
data were used to confirm the telemetry recorded on the data logger
files. The data showed:
03:32:57 Control Transfer from PPO-1 to PPO-2 took place
03:32:58 Feather Lever was in the stop position
03:33:01 Engine Out Detected Warning was displayed on the heads down
display
03:33:15 Lost Payload Video
03:33:48 Speed Priority Warning and Pitch Up Then Down
03:34:11 UA Entered a Left Turn
03:35:03 Lost All Telemetry and video Data
The replay of the recorded information also revealed that the pilot
who performed the mission setup
for the flight (not the accident pilot) programmed an initial
lost-link altitude of 9,000 feet and
an initial lost-link heading of 260 degrees.
Wreckage and Impact Information
The UA impacted the terrain in a sparsely populated desert area. The
geographic coordinates at the
accident site were: 31 degrees, 34.002 minutes north latitude; 110
degrees, 56.473 minutes west
longitude. The terrain elevation at the accident site was
approximately 3,803 feet above msl.
The wreckage path was located on the upslope of rapidly rising, rocky
desert terrain. The slope of
the terrain was approximately 45 degrees. Just before the initial
terrain impact were several
small scrub trees, which contained broken limbs. The angle of the
breaks was consistent with a
near wings level, relatively flat angle of impact. The wreckage path
was oriented upward along the
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rising terrain, on a heading of approximately 100 degrees, with the
main wreckage coming to rest on
a heading of 90 degrees.
The initial ground impact was near the base of the rising terrain. The
UA's vertical fin was
separated from the empennage and was located near the base of the
slope. The main portion of the
fuselage, the wings, and the empennage were located along the
up-sloping terrain near the crest of
the slope. Portions of the forward fuselage, avionics equipment, and
ballast from the forward
fuselage bay were located above the crest of the rising terrain. The
entire wreckage path was
approximately 95 feet long.
The forward section of the fuselage was separated from the rear
section near the forward fuel tank.
All of the fuselage fuel bladders were ruptured, and the odor of jet
aviation fuel was present.
The avionics bay had separated from the forward fuselage. The fuselage
from the aft fuel tank
rearward was damaged but primarily intact. The V-tail elevator
surfaces remained attached to the
empennage, and they were not damaged. The ventral fin and rudder were
separated from the empennage
and from each other and were found near the bottom of the rising
terrain.
The inboard sections of the left and right wings were located with the
main fuselage. A 7-foot
section of the outboard portion of the left wing was located in the
trees about 25 feet from the
debris field at the base of the rising terrain. The left wing's
leading edge was damaged, and the
forward spar was separated from the skin. The left inboard and
outboard flaps, along with the left
inboard aileron, remained attached to the portion of the wing that was
attached to the fuselage.
The left wing outboard aileron remained attached to the separated
outboard section of the left wing.
The inboard section of the right wing, which remained attached to the
fuselage, exhibited
leading-edge deformation, rearward crushing, and bending. The outboard
14 feet of the right wing
was detached from the inboard section of the wing and found near the
propeller. The right inboard
flap was separated from the wing, and the right outboard flap remained
attached. The ailerons
remained attached to the separated outboard section of the wing.
The left main landing gear was relatively intact and was found in the
extended position. The upper
portion of the right main landing gear strut remained attached to the
fuselage. The lower portion
of the right main landing gear strut and the tire were separated from
the upper portion of the
strut. The upper portion of the strut was extended from the fuselage.
The nose landing gear
separated from the fuselage in two pieces, and both were located near
the main wreckage.
The engine bay portion of the aft fuselage was largely intact. The
upper and lower engine access
panels remained attached to the fuselage. The signal from the
emergency locator transmitter (ELT)
was not detected during the search operations for the UA. Examination
of the ELT revealed that the
antenna cable was separated from the transmitter. The ELT was sent to
its manufacturer for
operational testing. The test results showed normal operation of the
ELT.
The propeller remained attached to the engine. As part of the
investigation, the blades were
arbitrarily marked A, B, and C. The A blade came to rest in the 12
o'clock position, blade B was
at the 4 o'clock position, and the blade C was at the 8 o'clock
position. Both the B and C blades
came to rest on an outcropping of rocks and boulders. The A blade
exhibited leading-edge nicks,
chordwise scratches, and gouges on its face. This blade was bent
toward its face and was loose in
the hub. The B blade exhibited gouges on its outboard face and was
bent toward the back of the
blade. The C blade exhibited gouges on its back, and it was bent
toward the face of the blade.
The propeller spinner exhibited localized crushing on its sides.
Localized areas of rotational
scarring were present on the sides of the spinner.
The UA was powered by a Honeywell TPE 331-10Y engine, serial number
P121015C. On-scene inspection
of the engine revealed the propeller pitch control setting was 89
degrees, the power lever angle
setting was 90 degrees, the underspeed governor setting was 32
degrees, and the hour meter for the
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engine read 498 hours. All of the engine control cables were connected
to their respective servos.
The engine controls moved when the servos were manipulated by hand.
Engine control continuity was
established to the servos. No fuel or oil leaks were noted in the
engine bay nor was any debris
noted in the inlet assembly ducting. Fluids consistent with engine oil
and jet fuel were found in
their respective hoses. Debris was found in the starter/generator
cooling duct. The
starter/generator rotated freely when its fan was turned by hand. The
left side igniter had an
area of white discoloration. The top igniter's tip contained debris
deposits. Mechanical
continuity of the engine was observed with the rotation of the
impeller, turbine rotor, and
propeller shaft. The drive-train connectivity to the oil scavenge pump
and to the fuel pump drive
shaft was observed in the scavenge port.
The engine was shipped to Honeywell for further examination, which was
accomplished on June 15,
2006. The fuel cutoff valve cover sustained impact damage. A liquid
consistent with jet fuel was
present at the fuel pump inlet and exited the fitting when the engine
was rotated opposite the
normal direction of rotation. The impeller was rotated, and resistance
to its rotation was
observed. The resistance increased when the engine was placed in a
nose-down attitude.
Examination of the gearbox found no anomalies. A borescope examination
of the power section
revealed no damage to the fuel nozzles. The first- and second-stage
compressors exhibited no
damage or rub marks. Examination of the first-stage turbine nozzle and
the third-stage turbine
revealed no damage. No anomalies were noted during the engine
examination.
The starter/generator was an engine accessory pad that was a driven,
air-cooled, brush-type unit.
The starter/generator and the generator control unit (GCU) were tested
at the manufacturer's
facility and found to be operational.
Tests and Research
Lockups
A lockup is any malfunction that causes the GCS PPO screens to stop
updating and to "freeze." A
review of the lockup events for BP-101 revealed that two lockups
occurred just before the launch of
the accident flight. A GA-ASI avionics technician stated that the
maintenance action to correct
the lockup was to switch the main processor circuit cards between
PPO-1 and PPO-2. This action
appeared to correct the problem, and the UA was able to depart.
A log that was kept in the GCS indicated that there had been 16
lockups involving BP-101 for
various reasons since December 12, 2005. These lockups occurred on
both PPO-1 and PPO-2. The log
did not provide any supporting data explaining the reason for the
lockups.
On May 15-16, 2006, testing was performed on the GCS in an attempt to
duplicate the lockups by
either simulating an aircraft flight or exercising the suspect circuit
boards using debug software.
All of the tests performed failed to duplicate the lockups.
Emergency Procedures
The emergency procedures for a rack switch and reboot, as found in the
checklist located within the
GCS state:
On rack taking control, verify all presets, hold modes, and control
commands are the same as the
current rack.
1. SAS [Stability Augmentation System] - On
2. IGNITION - HOT
3. STOP & FEATHER - Match Receiving PSO [Pilot/Sensor Operator]
4. SPEED LEVER - Match Receiving PSO
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Accident
04/25/2006
CHI06MA121
5. POWER LEVER - Match Receiving PSO
Verify all presets, hold modes, and control commands are the same.
With pilots in both seats (be prepared to switch back)
Additional Information
The UAS program began in August 2005 when the U.S. Border Patrol
granted a contract to GA-ASI to
develop the program. At the end of September 2005, BP-101 was flown to
FHU, and its first flight
was made operating within R2303. On October 1, 2005, the Office of Air
and Marine, Customs and
Border Protection, was formed. This office then became responsible for
the operation of the UAS
program. On October 4, 2005, BP-101 started flying missions.
Parties to the investigation were the FAA, CBP, GA-ASI, and Honeywell.
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Landing Facility/Approach Information
Airport Name
Runway Surface Type:
Runway Surface Condition:
Airport ID:
Type Instrument Approach:
VFR Approach/Landing:
Aircraft Information
Aircraft Manufacturer
Airworthiness Certificate(s):
Landing Gear Type:
Homebuilt Aircraft? Number of Seats:
Engine Type:
- Aircraft Inspection Information
Type of Last Inspection
- Emergency Locator Transmitter (ELT) Information
ELT Installed? ELT Operated?
Owner/Operator Information
Registered Aircraft Owner
Operator of Aircraft
Operator Does Business As:
- Type of U.S. Certificate(s) Held:
Air Carrier Operating Certificate(s):
Operating Certificate:
Regulation Flight Conducted Under:
Type of Flight Operation Conducted:
Operator Certificate:
Operator Designator Code:
Street Address
City
Street Address
City
ELT Aided in Locating Accident Site?
Time Since Last Inspection
Hours
Model/Series: Engine Manufacturer:
Date of Last Inspection
Model/Series
Certified Max Gross Wt. Number of Engines: LBS
Serial Number
Airport Elevation
Ft. MSL
Runway Used Runway Length Runway Width
Rated Power:
Airframe Total Time
Hours
State Zip Code
State Zip Code
No No Yes
Retractable - Tricycle
Aerial Observation
Public Use
None
Same as Reg'd Aircraft Owner
Same as Reg'd Aircraft Owner
DC Washington
1300 Pennsylvania Ave. NW
U.S. Customs and Border Protection
966
940 HP TPE-331 Honeywell Turbo Prop
1 10500 0 No
BP101 Predator B General Atomics
Forced Landing
Accident
04/25/2006
CHI06MA121
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First Pilot Information
Name
Sex: Seat Occupied:
City
Principal Profession: Certificate Number:
State Date of Birth Age
Certificate(s):
Airplane Rating(s):
Rotorcraft/Glider/LTA:
Instrument Rating(s):
Instructor Rating(s):
Type Rating/Endorsement for Accident/Incident Aircraft? Current
Biennial Flight Review?
Medical Cert. Status:
- Flight Time Matrix
Medical Cert.: Date of Last Medical Exam:
Glider
Lighter
Than Air
Rotorcraft
Instrument
Actual Simulated
Airplane
Mult-Engine
Night
Airplane
Single Engine
This Make
and Model
All A/C
Total Time
Pilot In Command(PIC)
Instructor
Last 90 Days
Last 30 Days
Last 24 Hours
Seatbelt Used? Shoulder Harness Used? Toxicology Performed? Second
Pilot?
Departure Time Time Zone State Airport Identifier
State Airport Identifier
Type of Flight Plan Filed:
Departure Point
Destination
Flight Plan/Itinerary
Type of Clearance:
Type of Airspace:
Weather Information
Source of Briefing:
Method of Briefing:
IFR
MST 1851
HFU AZ
Local Flight
Sierra Vista
IFR
No No
0 0 27 27
25 800 0 825
1000 1000 27 2545
650 1400 1200 27 3571
05/2005 Without Waivers/Limitations Class 1
02/2006
Airplane Multi-engine; Airplane Single-engine; Instrument Airplane
Flight Instructor; Commercial
Airplane
Multi-engine Land; Single-engine Land
None
On File Occupational Pilot M
35 On File On File On File On File
Accident
04/25/2006
CHI06MA121
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Weather Information
WOF ID Observation Time
Sky/Lowest Cloud Condition:
Time Zone WOF Elevation
Ft. MSL
WOF Distance From Accident Site
NM
Ft. AGL Condition of Light:
Direction From Accident Site
Deg. Mag.
Altimeter: "Hg
Density Altitude: Ft.
Visibility: SM
Wind Direction:
Ft. AGL
Weather Condtions at Accident Site:
°C °C Dew Point:
Gusts:
Lowest Ceiling:
Temperature:
Wind Speed:
Visibility (RVR): Ft.
Restrictions to Visibility:
Type of Precipitation:
Accident Information
Aircraft Damage:
Visibility (RVV) SM
Aircraft Fire:
Intensity of Precipitation:
Aircraft Explosion
Classification:
- Injury Summary Matrix
First Pilot
Second Pilot
Student Pilot
Check Pilot
Flight Engineer
Cabin Attendants
Other Crew
Passengers
- TOTAL ABOARD -
Other Ground
- GRAND TOTAL -
Fatal Serious Minor None TOTAL
Flight Instructor
1 1
1 1
1 1
None None Substantial
No Obscuration; No Precipitation
Visual Conditions
-10 10
30.00 10 None
Night Clear
140 10 3955 PST 0354 OLS
Accident
04/25/2006
CHI06MA121
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Administrative Information
Investigator-In-Charge (IIC)
Additional Persons Participating in This Accident/Incident
Investigation:
David Keenan
AAI-100
Pamela S. Sullivan
Accident
04/25/2006
CHI06MA121