Thunderbirds and Altimeters

[Dudley Henriques]

I've been back channeling for two days now with friends who are
ex-Thunderbirds and professional pilots in other professions. Most of us are
puzzled by the report although not at all puzzled by the results of
Stricklin's mistake!
There's something about this report some of us don't quite get, and it
concerns the zero set on the altimeters. The TB fly a zero set altimeter for
a show. It's not only basic for low altitude acro work, but it's specified
in the regulations for the Thunderbird mission and procedures. (the old
regulation anyway. haven't seen the revised one yet)
My guys however, were on the T38 team, and the TB regulation for practice
might have been changed since then. However, none of us believe that
Stricklin took off with the altimeter set for the elevation at Mountain
Home, which is 2996 feet ASL. That leaves only one scenario; that the
present Viper team must be using a MSL base at Nellis for practice because
of the mountains at Indian Springs. If this is true, then we still can't
figure out why Stricklin would reverse on the roof of his maneuver with a
target altitude of 1600 feet which is basically what happened. It just
doesn't make sense to us. If the team is using a MSL base at Nellis, and
Stricklin was using that base in his mind when he reversed; the elevation at
Nellis is 2000 feet. That would have put his reverse at 4500 feet for the
Viper instead of the 1600 plus he used. 1600 is way low for the Viper even
for a zero set altimeter reference It's very puzzling!!!
Also, there's been a lot of talk about not being able to zero altimeters at
some high elevation airports. This is puzzling also. The Kollsman range,
which is also the basic baro range in the Viper's CADC which drives the
Viper's altimeter in both ELECT and PNEU backup, is aprox 22.00 inches on
the low side and 32.00 inches on the high side. (I had to check this out
with some buddies of mine, as I'd forgotten the range in the Kollsman
myself!! :-)
This gives you, even figuring the 1 inch per thousand rule, an elevation
reset capability to a zero reset before takeoff of 10, 000 feet. This
basically allows a zero reset anywhere in the U.S. at least, allowing for a
standard atmosphere. I don't think I'm missing anything here, but I might
have.....getting older you know!! :-) I just can't remember a zero set being
any problem for me during my tenure as a demonstration pilot.
The Thunderbird's are locked up tighter than a drum right now, and answers
from the present team are not easy to get; so the bottom line so far for us
old timers trying to figure this out is that the team indeed does use a MSL
reference at Nellis because of the mountains, but resets to a zero altimeter
set before takeoff at the show site. If this is the case, it's
understandable to me how Chris Stricklin could have made the mistake he did.
I'll tell you up front. I can sympathize with Chris Stricklin, or anyone
else for that matter who has to work low altitude acro this way. If there's
one thing that will kill you doing low work it's non-standardization. If the
Birds have to use a MSL calculation for their roof target altitudes at
Nellis for a vertical plane maneuver because of the mountains, then revert
to a zero set when doing a show; that in my opinion is bad news! It's only a
matter of time when things like this catch up to you when doing low work in
high performance airplanes.
Chris Stricklin is a damn good pilot. He's also a damn lucky pilot!
What happened to Stricklin has happened to a lot of very good pilots who do
low work. If all this reporting is true, he was simply bitten by non
standardization! I understand the situation's being looked at closely by the
Air Force. That's one good thing anyway, although I don't see how they're
going to change anything unless they can take the mountains at Nellis out of
the Thunderbird equation.
Frankly, the whole damn thing is puzzling to us; us being myself and a few
ex-Thunderbirds. I know I'll probably pick up the straight scoop sooner or
later through my grapevine, but for right now, this report, and putting it
together for a clear picture of what happened to Stricklin is one large
puzzle in progress.
Dudley Henriques
International Fighter Pilots Fellowship
Commercial Pilot/ CFI Retired
For personal email, please replace
the z's with e's.
dhenriquesATzarthlinkDOTnzt

[John R Weiss]

"Dudley Henriques" > wrote...

> The Kollsman range,
> which is also the basic baro range in the Viper's CADC which drives the
> Viper's altimeter in both ELECT and PNEU backup, is aprox 22.00 inches on
> the low side and 32.00 inches on the high side.

> This gives you, even figuring the 1 inch per thousand rule, an elevation
> reset capability to a zero reset before takeoff of 10, 000 feet. This
> basically allows a zero reset anywhere in the U.S. at least, allowing for a
> standard atmosphere.

Not quite...

You have a 10,000' nominal range using that rule of thumb, but from the 29.92"
standard you only have 7,920' of 'low' correction available at sea level, and
2080' of 'high' correction. That gives you QFE capability up to an airport
elevation of 7,920'. Still, as you say, adequate for most US airports in most
conditions.

It also illustrates the complexity in attempting to fly IFR using QFE (0' runway
altitude) at high-altitude airports. If you use the wrong setting, misinterpret
a controller's QFE / QNH call, or use the wrong minimums on a chart, it can be
deadly. Those errors are all too easy to make, especially if you are not used
to using QFE at all.

[Mike Marron]

>"Dudley Henriques" > wrote:

[snipped for brevity]

>There's something about this report some of us don't quite get, and it
>concerns the zero set on the altimeters. The TB fly a zero set altimeter for
>a show. It's not only basic for low altitude acro work, but it's specified
>in the regulations for the Thunderbird mission and procedures

What puzzles me isn't whether or not he zeroed the altimeter prior to
launch or was attempting to convert AGL elevations to MSL altitudes,
but rather why he failed to recognize via outside visual cues that he
was simply too low to the ground to even THINK about initiating a
Split-S maneuver.

Clearly, he knew that something was wrong early on since he reportedly
exerted "maximum back stick pressure and rolled slightly left to
ensure the aircraft would impact away from the crowd should he
have to eject." Despite his exceedingly close proximity to the ground
the fact that he managed to eject successfully is another indication
that he realized quite early on that he done screwed up!

If you look at the cockpit video it's obvious that his head is tilted
way back watching the horizon while he was inverted prior to initating
the Split-S. My primary question is why he didn't abort the Split-S
and simply continue the roll at the top of the maneuver and perform
an Immelmann instead of pressing on with the Split-S?

[Dudley Henriques]

"Mike Marron" > wrote in message
...
> >"Dudley Henriques" > wrote:
>
> [snipped for brevity]
>
> >There's something about this report some of us don't quite get, and it
> >concerns the zero set on the altimeters. The TB fly a zero set altimeter
for
> >a show. It's not only basic for low altitude acro work, but it's
specified
> >in the regulations for the Thunderbird mission and procedures
>
> What puzzles me isn't whether or not he zeroed the altimeter prior to
> launch or was attempting to convert AGL elevations to MSL altitudes,
> but rather why he failed to recognize via outside visual cues that he
> was simply too low to the ground to even THINK about initiating a
> Split-S maneuver.
>
> Clearly, he knew that something was wrong early on since he reportedly
> exerted "maximum back stick pressure and rolled slightly left to
> ensure the aircraft would impact away from the crowd should he
> have to eject." Despite his exceedingly close proximity to the ground
> the fact that he managed to eject successfully is another indication
> that he realized quite early on that he done screwed up!
>
> If you look at the cockpit video it's obvious that his head is tilted
> way back watching the horizon while he was inverted prior to initating
> the Split-S. My primary question is why he didn't abort the Split-S
> and simply continue the roll at the top of the maneuver and perform
> an Immelmann instead of pressing on with the Split-S?

This is our observation exactly! Pilots who survive low altitude demo work
are NOT one cue pilots, but respond to multiple cues, many peripheral. All
of us discussing this back channel are in complete agreement with your
observation about visual cues.
The g line required to put the Viper in reverse at 1600 was higher than that
which would have been normal. This should have been a physical cue. The
horizon is different at 1600 than at 2500. This is a visual cue.
The inverted ground area showing past the canopy bow edge is wider (more
detailed ground area meets the eye) at 1600 than at 2500. This is a
peripheral visual cue.
The inverted pull is escapable in roll until just before exact vertical. The
shortest way out using roll must allow for snatch factor and roll rate and
this occurs in an airplane with the Viper's roll capability in this maneuver
profile at just before 90 degrees nose down. From then on it's a straight
pull commit. The Viper can be flown into a pitch rate defeat on the limiter
and that's where he put it apparently. I make it a dead airplane from 90
degrees nose down in the pull and a dead pilot except for the seat
capability.
The altimeter reference however, remains a puzzle for us.
Dudley

[Dudley Henriques]

"John R Weiss" > wrote in message
news:eHbRb.152481$I06.1538887@attbi_s01...
> "Dudley Henriques" > wrote...
>
> > The Kollsman range,
> > which is also the basic baro range in the Viper's CADC which drives the
> > Viper's altimeter in both ELECT and PNEU backup, is aprox 22.00 inches
on
> > the low side and 32.00 inches on the high side.
>
> > This gives you, even figuring the 1 inch per thousand rule, an elevation
> > reset capability to a zero reset before takeoff of 10, 000 feet. This
> > basically allows a zero reset anywhere in the U.S. at least, allowing
for a
> > standard atmosphere.
>
> Not quite...
>
> You have a 10,000' nominal range using that rule of thumb, but from the
29.92"
> standard you only have 7,920' of 'low' correction available at sea level,
and
> 2080' of 'high' correction. That gives you QFE capability up to an
airport
> elevation of 7,920'. Still, as you say, adequate for most US airports in
most
> conditions.

Yeah, that's right JW. There's a positive/negative factor in there above
that 29.92 that splits that 10K.
>
> It also illustrates the complexity in attempting to fly IFR using QFE (0'
runway
> altitude) at high-altitude airports. If you use the wrong setting,
misinterpret
> a controller's QFE / QNH call, or use the wrong minimums on a chart, it
can be
> deadly. Those errors are all too easy to make, especially if you are not
used
> to using QFE at all.

This really points out why a zero setting should ONLY be used for aerobatic
work, and even then, only for LOCAL aerobatic work!!
Dudley

[Dudley Henriques]

"Dudley Henriques" > wrote in message
link.net...
>
> "John R Weiss" > wrote in message
> news:eHbRb.152481$I06.1538887@attbi_s01...
> > "Dudley Henriques" > wrote...

> Yeah, that's right JW. There's a positive/negative factor in there above
> that 29.92 that splits that 10K.

That should be above AND below 29.92!!! :-)
D

[S. Sampson]

What I don't understand, is why he didn't realize he was too low when
he rolled over and looked down? Seems like if he's done this for awhile
he would get a sense of good and bad? But maybe being on the road
and all the different locations they fly makes this a poor judgment tool.

Watching the cockpit video, the ground sure looks close to me, as the
B-52's on the ramp are filling the window :-)

"Dudley Henriques" > wrote
>
> I've been back channeling for two days now with friends who are
> ex-Thunderbirds and professional pilots in other professions.

[S. Sampson]

"Mike Marron" > wrote
>
> My primary question is why he didn't abort the Split-S
> and simply continue the roll at the top of the maneuver and perform
> an Immelmann instead of pressing on with the Split-S?

He would have had to buy the first round at the club for missing the
maneuver, and everyone would have bought him a round if he somehow
pulled it out of his ***. Ah well, no one went to the club that day...

[Dudley Henriques]

It looks like a simple mistake really. What it amounts to is that he
mentally used the reference altitude the team uses at Nellis which put him
800 feet low on the roof. This kind of lapse can happen; just not in the low
altitude aerobatic business! The physical and visual cues missed I have no
answer for. You either see them or you don't. You don't have time to
mentally calculate. Your mind, eyes, and body either pick up on these things
or they don't. Somehow, he missed the cues. They were there. I know they
were there because I've seen and felt them myself many times doing exactly
what he was doing. It's almost impossible to explain to people who haven't
actually flown low altitude demonstration work. Anyway, he made it. He won't
get a chance to try it again, but it looks like the AF has learned enough
from this to make a few corrections that might help the next guy down the
road!
Dudley Henriques
International Fighter Pilots Fellowship
Commercial Pilot/ CFI Retired
For personal email, please replace
the z's with e's.
dhenriquesATzarthlinkDOTnzt
"S. Sampson" > wrote in message
news:dphRb.1296$Q_4.438@okepread03...
> What I don't understand, is why he didn't realize he was too low when
> he rolled over and looked down? Seems like if he's done this for awhile
> he would get a sense of good and bad? But maybe being on the road
> and all the different locations they fly makes this a poor judgment tool.
>
> Watching the cockpit video, the ground sure looks close to me, as the
> B-52's on the ramp are filling the window :-)
>
> "Dudley Henriques" > wrote
> >
> > I've been back channeling for two days now with friends who are
> > ex-Thunderbirds and professional pilots in other professions.
>
>

[Nick Coleman]

Without pre-judging this pilot, what happens to a pilot who makes a mistake
and totals the aircraft? Out of the team? or out of the AF completely?

Nick

[Steve R.]

Video?? There's video and I missed it??? Drat! Anybody have a link to it?
Please? :o)
Steve R.


"Mike Marron" > wrote in message
...
> If you look at the cockpit video it's obvious that his head is tilted
> way back watching the horizon while he was inverted prior to initating
> the Split-S. My primary question is why he didn't abort the Split-S
> and simply continue the roll at the top of the maneuver and perform
> an Immelmann instead of pressing on with the Split-S?

[Dudley Henriques]

"Nick Coleman" > wrote in message
...
>
> Without pre-judging this pilot, what happens to a pilot who makes a
mistake
> and totals the aircraft? Out of the team? or out of the AF completely?
>
> Nick

Last word I have is that he's been transferred down to DC at the Pentagon.
It's a desk job for sure if you survive this kind of mistake. But make no
mistake yourself in judging Chris Striklin. He's a good pilot. He never
would have gotten a slot on the team if he wasn't. He just got caught up in
an error. He made a mistake.
He was lucky. He's still a good pilot and a fine officer. It's just that you
can't make this kind of mistake and remain a Thunderbird. It's impossible.
The team has learned something and will move on retaining that
knowledge....hopefully using it to good advantage in the future. It's a done
deal.
Dudley Henriques
International Fighter Pilots Fellowship
Commercial Pilot/ CFI Retired
For personal email, please replace
the z's with e's.
dhenriquesATzarthlinkDOTnzt
Dudley Henriques
International Fighter Pilots Fellowship
Commercial Pilot/ CFI Retired
For personal email, please replace
the z's with e's.
dhenriquesATzarthlinkDOTnzt

[Mike Marron]

>"Steve R." > wrote:
>>"Mike Marron" > wrote:

>>If you look at the cockpit video it's obvious that his head is tilted
>>way back watching the horizon while he was inverted prior to initating
>>the Split-S. My primary question is why he didn't abort the Split-S
>>and simply continue the roll at the top of the maneuver and perform
>>an Immelmann instead of pressing on with the Split-S?

>Video?? There's video and I missed it??? Drat! Anybody have a link to it?
>Please? :o)
>Steve R.

Subject: Thunderbird pilot found at fault in Mountain Home AFB crash
Newsgroups: rec.aviation.military
Date: 2004-01-25 22:59:09 PST

http://www.avweb.com/eletter/archives/avflash/190-full.html#186582

[Steve R.]

Ummm.... nevermind. I saw the link later while i was reading a different
thread. Thanks though! :o)
Steve R.


"Mike Marron" > wrote in message
...
> >"Dudley Henriques" > wrote:
>
> [snipped for brevity]
>
> >There's something about this report some of us don't quite get, and it
> >concerns the zero set on the altimeters. The TB fly a zero set altimeter
for
> >a show. It's not only basic for low altitude acro work, but it's
specified
> >in the regulations for the Thunderbird mission and procedures
>
> What puzzles me isn't whether or not he zeroed the altimeter prior to
> launch or was attempting to convert AGL elevations to MSL altitudes,
> but rather why he failed to recognize via outside visual cues that he
> was simply too low to the ground to even THINK about initiating a
> Split-S maneuver.
>
> Clearly, he knew that something was wrong early on since he reportedly
> exerted "maximum back stick pressure and rolled slightly left to
> ensure the aircraft would impact away from the crowd should he
> have to eject." Despite his exceedingly close proximity to the ground
> the fact that he managed to eject successfully is another indication
> that he realized quite early on that he done screwed up!
>
> If you look at the cockpit video it's obvious that his head is tilted
> way back watching the horizon while he was inverted prior to initating
> the Split-S. My primary question is why he didn't abort the Split-S
> and simply continue the roll at the top of the maneuver and perform
> an Immelmann instead of pressing on with the Split-S?
>
>
>
>
>
>
>
>

[John Keeney]

"Dudley Henriques" > wrote in message
ink.net...
>
> "John Carrier" > wrote in message
> ...
> > I've observed similar results with new students in the T-45C. The
primary
> > instrument scan is on an ADI which has all the essential flight data for
> BI.
> > But the altimeter and airspeed are presented as digital information with
a
> > "wiper blade" for movement (roughly 2 knot and 20 foot increments ...
one
> > sweep = 100 knots or 1000 feet). Not intuitive for the pilot trained to
> > standard instrumentation. We do not have BI-1 check rides.
> >
> > There are backup steam guages ... 2 inch airspeed and altimeter ... that
> are
> > well out of scan. A partial panel scan is tough. Of course I can dump
> the
> > system and leave them with a wet compass, a peanut gyro, a clock and the
> > standby pitot statics. Fun to fly a TACAN approach using the
alphanumeric
> > bearing to station and DME. Kind of a graduation character building
> > exercise, the Kobiyashi Maru scenario.
> >
> > R / John
>
> Hi JC
>
> I've lived through the perfect Kobiyashi Maru scenario. I have beaten
> Captain Kirk. I am the best!!!
> My wife appeared at the head of the stairs one night before we went out
for
> dinner and asked me,
> "Do I look fatter in the blue dress.....or the red one????"
> "NEITHER, says me, thou art beautiful in BOTH!!!!"

Well then, you won't mind telling us when you quit beating her?

[Dudley Henriques]

"John Keeney" > wrote in message
...
>
> "Dudley Henriques" > wrote in message
> ink.net...
> >
> > "John Carrier" > wrote in message
> > ...
> > > I've observed similar results with new students in the T-45C. The
> primary
> > > instrument scan is on an ADI which has all the essential flight data
for
> > BI.
> > > But the altimeter and airspeed are presented as digital information
with
> a
> > > "wiper blade" for movement (roughly 2 knot and 20 foot increments ...
> one
> > > sweep = 100 knots or 1000 feet). Not intuitive for the pilot trained
to
> > > standard instrumentation. We do not have BI-1 check rides.
> > >
> > > There are backup steam guages ... 2 inch airspeed and altimeter ...
that
> > are
> > > well out of scan. A partial panel scan is tough. Of course I can
dump
> > the
> > > system and leave them with a wet compass, a peanut gyro, a clock and
the
> > > standby pitot statics. Fun to fly a TACAN approach using the
> alphanumeric
> > > bearing to station and DME. Kind of a graduation character building
> > > exercise, the Kobiyashi Maru scenario.
> > >
> > > R / John
> >
> > Hi JC
> >
> > I've lived through the perfect Kobiyashi Maru scenario. I have beaten
> > Captain Kirk. I am the best!!!
> > My wife appeared at the head of the stairs one night before we went out
> for
> > dinner and asked me,
> > "Do I look fatter in the blue dress.....or the red one????"
> > "NEITHER, says me, thou art beautiful in BOTH!!!!"
>
> Well then, you won't mind telling us when you quit beating her?

Not sure if I follow? KM is a no win scenario offered in a problem.
(Wife with two dresses vs appearance = no win)
By attacking the problem source and changing the premise, you create a
possible win scenario (survival in this case.......and creative
thinking.......and in the case of not offering my wife a fat in one, not in
the other ......a sure formula for avoiding instant execution!!! :-)
Dudley Henriques
International Fighter Pilots Fellowship
Commercial Pilot/ CFI Retired
For personal email, please replace
the z's with e's.
dhenriquesATzarthlinkDOTnzt

[Kirk Stant]

Mike Marron > wrote in message >...
>
> Well then, there ya' go!! Here in Florida it's flatter than Sabrina
> the Teenage Witch but if I flew in mountainous terrain like you I'd
> roll in the field elevation prior to launch myself.

Roger that, I've spent some time running up and down Florida in both
F-4s and bugsmashers; not a lot of terrain to hide behind! If I
remember right, the highest spot is near Crestview, about 243ft above
sea level. Most places you are within the tolerance of the altimeter!
(75ft)

> Anyone who needs two altimeters to shoot an instrument approach has
> no business flying in the soup in the first place. Airport elevations
> are clearly depicted on the approach plates and if one is unable to
> compute his height above the ground after quickly glancing at his
> altimeter with the correct altimeter setting can expect to auger in
> exactly like poor ol' Cap'n Stricklin did.

Apparently it's a big thing "over there", maybe they were too cheap to
buy a radar altimeter? But hey if it works, so be it. Anyone else
have experience shooting approaches with QFE set on an altimeter?

> Furthur, we don't generally (that word again! ;) use cryptic "QFE" or
> "QNH" catch phrases in the U.S. Instead, simply say "AGL" or
> "MSL" and you'll less likely be misunderstood since said terminology
> is the accepted practice here in the U.S. not to mention much more
> intuitive than those steenkin' European Q-codes are.

Standard ICAO terminology (just like these stupid Class B airspaces -
I want my TCA's back!). And there is a difference: QFE means setting
your altimeter to the kollsman setting that will result in a 0 ft
reading at touchdown - NOT "AGL". It's only AGL at touchdown (unless
you are flying over a really big pool table...or Florida). QNH is the
same as our local altimeter setting, gives pressure altitude, which is
approximately MSL altitude until above the transition level, then its
only a reference pressure altitude. But you already knew all that, of
course.

> Evidently you still don't understand the problem. The statement above
> was referring to Stricklin's stunning lapse of judgment that resulted
> in him attempting to perform a Split-S maneuver despite the fact he
> was way too low.

Oh believe me, I know exactly what the problem is. Doing pops on the
bombing range required the exact same figuring of the pull-down and
apex altitude, and if you miscalculated or rolled and pulled too low
or too tight you would at best drop a lousy bomb and lose some
quarters; if you really pooched it you could easily end up dead. Lost
some good friends that way. And you absolutely could not depend on
visual cues - especially if it was a first look target, and the
approach terrain wasn't at the same elevation as the target, etc. You
plan the flight, and fly the plan, and if it doesn't look right you
abort. Stricklin didn't fly the plan (for whatever reason), then
waited a bit too long to abort, that's all. Damn glad he got out!

> Best of luck there (flying gliders, it'll be a loooong recovery!)

No recovery needed or planned, thank you - Racing glass is the only
way to fly!

Happy aviating,

Kirk

[[email protected]]

Dudley Henriques > wrote:

> The problem is that the pilots can brief for the right target and then miss
> it if the concentration is broken. In this incident, the visuals were missed
> as well. It was a multiple error. It involves broken concentration, and this
> is the main issue in these accidents. Everyone involved in low altitude work
> knows that there are multiple cues and what they are.

I saw an interesting program on Discovery, or maybe The Learning Channel,
a few days ago. It dealt with visual perception. One experiment/example
they used was showing a group of people (about 15 or 20) a film of people
practicing basketball. The group was told to try to count the number
of balls in use. At the end the group was asked if they had seen anything
unusual in the film. About 1/4 to 1/3 of the group raised their hands.
When they played back the film again it turned out the big majority had
just plain not seen a guy in a gorilla suit walk right through the scene.

Visual perception depends a lot on what we expect to see, so it is easy
to believe that a person could miss the visual cues until it was too late
if he was not expecting a problem.

Bill Ranck
Blacksburg, Va.