Dudley Henriques wrote in
:

Bertie the Bunyip wrote:
Dudley Henriques wrote in
:


Didn't see the T6 roll on these links, but I think I remember the
crash. The 6 has a lousy roll rate and loses energy like a brick
when rolling and doing 2 in a row while down in the weeds can bite
you in the butt dishing out. More than one guy's lost a T6 this way.

Yeah, gave you the wrong one the sifrst time and couldn't get it when
I replied. Youtube seemed to be down or something. Still is. He just
did a single roll. It's pretty obvious from the get go that he hasn't
got a chance. By the time he's 90 deg left the nose is well down on
the horizon and he's commited to some major thrashinbg around on the
elevators and rudder to keep the thing goin which degenerates into
dishing out of the bottom in a big way towards the end. I am
surprised about your comments on it losing energy, though..
The Cobra; his best chance would have been to anticipate the torque
roll carrying all that MP and throttle back to idle before it
torqued out on him, then rolling to the nearest horizon after a
mistake like he made on the way up. In certain conditions you just
don't get a second chance in prop fighters.


OK, that makes sense. I get the feeling he was a bit surprised by the
time he reached the 3/8ths point of the loop and had no real plan
out. They do teach this nowadays, right? I was quizzed mercilessly
about escape routes from all sorts of fjukkups (all of which I had a
good answer for) by the FAA inspector that signed my waiver. Do
inspectors even do those anymore? Evrythng else seems to be done by
someone else these days.





Bertie


The Cobra was a perfect example of something every pilot who flies
these hot prop fighters in demonstrations should be told on the very
first day a check pilot works with them.
First thing you learn is that if you have to think about it, you
shouldn't be doing it...period! The second thing you learn is that
money and horsepower don't necessarily equate.
All of these guys have egos. If they didn't, they wouldn't be
demonstrating a prop fighter at low altitude. Ego is fine, but you
leave that on the ground or sooner or later it dies with you in these
airplanes. The first thing you do when you work with these pilots is
take away that ego and replace it with a deep respect for the
airplane. Trust me, those things can kill you quicker than a
rattlesnake strike. Complacency will kill you in prop fighters. The
only way you can demonstrate a prop fighter at low altitude and live
to retire and talk about it is to develop a keen respect for the
airplane even more keen than any airplane you have ever flown or ever
will fly. The next thing is consistency. Bob Hoover is alive today
because of consistency. Every maneuver he does is like it was cut out
of a template. His g profiles in his pulls and his top gate parameters
are as consistent as a finely tuned swiss watch. He seldom varies more
than a few feet in altitude and a few knots in airspeed, and his
application of g is totally predictable.
Predictability is the key to survival when demonstrating an airplane
like a Mustang, Spitfire, or a King Cobra.
There is a killer up there and it rides with you all the time. Neglect
it for only an instant and you're history. It's a game that has to be
played right the first time....every time....period!

You have an issue with these high powered prop fighters that you don't
have in any other kind of airplane when it comes to demonstration
flying at low altitude. This issue concerns what happens when these
airplanes get too slow, have too much angle of attack on the wing, and
are carrying high amounts of manifold pressure.
Just to give you some idea of exactly how powerful these airplanes
are, consider for a moment that a P51 will actually jump it's wheel
chocks at 40 inches. You can't hold it!
Now, put one of the fighters on top approaching a critical low
altitude top gate after losing all your maneuvering airspeed to
positive g on the way up there; now throw in a high power setting and
a mushing nose rate as an 11 foot prop disk rotates through the air in
pitch and what do you get? You get a King Cobra severely being
impacted by torque in roll, severe P Factor with the prop sensing a
relative wind; and as the prop disk rotates; gyroscopic precession 90
degrees to the pitch axis. As if all this wasn't enough, with the high
power setting, he had spiraling slipstream forces acting on the
airplane in yaw as well. As the man says, "this just ain't no place
for a sane person to be"

The Cobra had all these things in play, and it really messed him up
badly from what I saw. He had all this mess going on at the same time.

It looked like he tried to salvage it, but instead of cutting the
power and rolling to the nearest horizon throttled back as he should
have done, then repositioning, continuing his routine by recapturing
the show line and continuing, he tried to stay with it and ride it
out. The result was a rolling yawing motion almost surely behind the
max CL curve with a lot of mush on the airplane. Naturally this worked
itself out for him as the wing recovered some workable angle of attack
but by then it was way too late. He had no g available that would
recover the airplane on the front side of a high speed stall before
impacting the ground; a classic coffin corner vertical recovery
failure.


OK, that all makes sense. I've never flown anything this powerful, but
if an immelman was going badly for me I would just transform it into a
half cuban rather than try to roll level with too little speed. With the
power available torque was still and issue, but it wasn't the bomb that
it is on these contraptions, obviously. It's amazing to watch the
difficulty they have regaining a bit of grip once it;s gone..


Bertie