Who's At Fault in UAV/Part91 MAC?

On Sat, 24 Apr 2004 15:42:46 GMT, "Tony Cox" wrote in
Message-Id: . net:

"Larry Dighera" wrote in message
.. .
On Fri, 23 Apr 2004 16:09:19 GMT, "Tony Cox" wrote in
Message-Id: et:

I suppose that depends on how you define "Aircraft"
and "pilot"...


Ummm..

Pilot: A person who holds the appropriate category, class, and type
rating, if appropriate, for the conduct of the flight.

Aircraft: A device that is used or intended to be used for flight in
the air.

I was being "Clintonesque".

I know, but today that's the way government works.

These definitions from the FAR's? I
couldn't find them on a quick scan.


FAR Part I

On Sat, 24 Apr 2004 11:44:10 -0400, "Barry" wrote in
Message-Id: :

Fortunately, the chances you cite are not criteria for NAS design.

In engineering a workable NAS I would prefer that the designers employ
methodologies that _insure_ separation of air traffic, not merely
reduce the _chances_ of a MAC. Anything less is irresponsible
negligence.

In any system, there's always a small probability that a catastrophe will
occur. Aircraft certification rules and separation standards acknowledge this
and are established to keep the risk acceptably low. For example, for lateral
separation of two aircraft traveling at the same flight level on parallel
routes, the Target Level of Safety (TLS) set by ICAO (with FAA participation)
is 5 x 10^-9 per flight hour. That is, loss of lateral separation should
lead to no more than one accident every 200 million flight hours. The TLS is
not zero. Some people don't like to accept this, but it's just not realistic
to insist on zero risk.

Barry


Thank you for the information.

How would the TLS be affected if the Big Sky theory were relied upon
for aircraft separation as John T. suggested?

"Mike Money" wrote in message
...

The Predator is equipped with a modified Honeywell ETCAS TPA-81A. The
system responds to Mode 1, 2, 3, 4, A, C, and S. Forward surveillance
has been extended to 360 degrees.

What do you mean by 360 degrees? What is the resolution? Better or
worse than someone with 20/40 vision? Is there collision detection
software analyzing the incoming video, or does it just rely on the ground
based operator to see what's going on.

And of course not all GA aircraft are equipped with TCAS, nor are
they required to be.


In addition, Predator is data-linked to airborne and ground commands for
control and observation.

From the crash reports that Larry provided, this seems to be a ground
link which is easily obscured by terrain. I'd have thought some satellite
link would be better.


Predator is piloted by a ground controller who is assisted by up to six
(6) mission specialist. Each specialists is responsible for the
sensor/system he/she is operating to complete the mission (optical, IR,
armament, etc.). The pilot ground controller is dedicated to flying the
airplane. Some controllers are certified pilots and all controllers
have spent many hours in a simulator.

"Some" are certified pilots??? Come on now.

I bet there are millions of little weenies with hundreds of hours
of Microsoft FS under their belts, but I certainly wouldn't want them
flying around in the same sky as me and my passengers.


There are more eyeballs on a Predator and its proximity to everything
than any GA aircraft.

It's not "eyeballs on a Predator" that concern me. It's the
eyeballs the Predator has looking out for other traffic and
the competence of those interpreting what they see which
is the safety concern.

In the final analysis, the operator of a Predator just has his
job on the line; I have my life on the line, and that of my
passengers.

Tell you what. How about fitting operators with a helmet
that has a built-in gun pointing directly into his head? If they
hit another plane, the gun goes off.

"Ace Pilot" wrote in message
om...
How is see-and-avoid handled with unmanned weather balloons? Are they
only released in restricted airspace? Seems to me that there are some
parallels with UAVs.

Aircraft are obliged to give priority to balloons, unmanned or not.
No one has asserted that UAVs have priority over aircraft.

Anyway, balloons don't converge on you from your blind side.

"Peter Gottlieb" wrote in message
. ..

Heck, why don't they try giving the job to CAP and see how well that
concept
works?

Around here (Las Vegas, NV), they do. Not sure how successful
they are...

How would the TLS be affected if the Big Sky theory were relied upon
for aircraft separation as John T. suggested?

I'm not very familiar with this subject, but you can read "Safety
Considerations for Operation of Small Unmanned Aerial Vehicles in
Civil Airspace" produced by the MIT International Center for Air
Transportation:

http://icat-server.mit.edu/Library/f....cgi?idDoc=205

They studied both midair collisions and exposure to people on the ground. The
relevant conclusions for midairs:

Significant Amount of Airspace with Exposure Risk
Below the Target Level of Safety
- Areas around major airports are above the TLS

Opportunities may exist to allow a class of small
UAV’s to operate with limited restrictions
- Limiting operation in airspace near airports
may achieve TLS

Mitigation Strategies Are Available to Further Reduce the Risk
-Vehicles can be designed with capabilities to limit
likelihood of midair collisions

Barry

"John T" wrote in message
ws.com...

For all the VFR flight I've
done, the only time I have ever gotten close to another craft
unintentionally was near an airport. See and avoid? Perhaps, but I don't
recall ever maneuvering to avoid another aircraft during VFR cruise.

Perhaps your good fortune or lack of attention has lulled you into
a false sense of security. In my 500+ hours, I've been almost dinged
twice -- once some 20 miles out from Pasa Rubles and once in the
middle of nowhere. Both were near head-ons. And I'm willing to bet
that there have been more I've not been aware of, since in both cases
the occupants displayed no reaction to my presence whatsoever.

"Tony Cox" wrote in
ink.net:

Perhaps your good fortune or lack of attention has lulled you into
a false sense of security. In my 500+ hours, I've been almost dinged
twice -- once some 20 miles out from Pasa Rubles and once in the
middle of nowhere. Both were near head-ons. And I'm willing to bet
that there have been more I've not been aware of, since in both cases
the occupants displayed no reaction to my presence whatsoever.

I've had dozens of close calls, several of which required very abrupt
maneuvers to avoid collision, most of them far from airports. The big sky
theory is just that, a theory.

--
Regards,

Stan

"Barry" wrote in message
...

How would the TLS be affected if the Big Sky theory were relied upon
for aircraft separation as John T. suggested?

I'm not very familiar with this subject, but you can read "Safety
Considerations for Operation of Small Unmanned Aerial Vehicles in
Civil Airspace" produced by the MIT International Center for Air
Transportation:

http://icat-server.mit.edu/Library/f....cgi?idDoc=205

They studied both midair collisions and exposure to people on the ground.
The
relevant conclusions for midairs:

Significant Amount of Airspace with Exposure Risk
Below the Target Level of Safety
- Areas around major airports are above the TLS

Opportunities may exist to allow a class of small
UAV's to operate with limited restrictions
- Limiting operation in airspace near airports
may achieve TLS

Mitigation Strategies Are Available to Further Reduce the Risk
-Vehicles can be designed with capabilities to limit
likelihood of midair collisions

This study attempts to 'bound' the danger through a Bayesian
analysis of engine failure probability and chances of hitting
something at random in the airspace 'per flight hour'. In high
traffic areas, the probability is small (10-8). But the total
accident rate will depend on how many of these things are
flying around. There is nothing about 'accountability' in the
"Mitigation Strategies", which is very odd since accountability
looms very large in current aviation practice (and FAA regulation).

I'm concerned that the model for this sees a UAV "pilot" as a
sort of hands-on air traffic controller, rather than as a proper
"pilot" with the attendant certification and responsibility
requirements. This is a major departure from existing practice,
and potentially devastating for GA.

"Tony Cox" wrote in message
ink.net...
"Barry" wrote in message
...

How would the TLS be affected if the Big Sky theory were relied upon
for aircraft separation as John T. suggested?

I'm not very familiar with this subject, but you can read "Safety
Considerations for Operation of Small Unmanned Aerial Vehicles in
Civil Airspace" produced by the MIT International Center for Air
Transportation:

http://icat-server.mit.edu/Library/f....cgi?idDoc=205

They studied both midair collisions and exposure to people on the
ground.
The
relevant conclusions for midairs:

Significant Amount of Airspace with Exposure Risk
Below the Target Level of Safety
- Areas around major airports are above the TLS

Opportunities may exist to allow a class of small
UAV's to operate with limited restrictions
- Limiting operation in airspace near airports
may achieve TLS

Mitigation Strategies Are Available to Further Reduce the Risk
-Vehicles can be designed with capabilities to limit
likelihood of midair collisions

This study attempts to 'bound' the danger through a Bayesian
analysis of engine failure probability and chances of hitting
something at random in the airspace 'per flight hour'. In high
traffic areas, the probability is small (10-8). But the total
accident rate will depend on how many of these things are
flying around. There is nothing about 'accountability' in the
"Mitigation Strategies", which is very odd since accountability
looms very large in current aviation practice (and FAA regulation).

I'm concerned that the model for this sees a UAV "pilot" as a
sort of hands-on air traffic controller, rather than as a proper
"pilot" with the attendant certification and responsibility
requirements. This is a major departure from existing practice,
and potentially devastating for GA.

I had an opportunity to speak with a Marine who operates UAVs as the remote
pilot. He said he and others doing that job must be instrument rated pilots
and the UAV must be on an IFR flight plan. Given that, why would the
accident rate for UAVs be any different than normal IFR traffic?