Walter's nasty surprise.

[gomwolf]

Recently I reading 'Luftwaffe Eagle' by Walter Schuck again. It is good memoir. It is fun to read, have many good episodes, and you can get many tactical information. However Still I cannot understand well this evasion maneuvering Walter developed. This is an excerpt of 'Luftwaffe Eagle'.

"If an enemy fighter was on my tail, I would start by climbing steeply, but would then execute a half roll and at the same time tramp hard on the rudder. While machine still yawing throught 180 degrees on its back, I would complete the roll by use of the ailerons, dive sharply in to another 180-degree turn and, with the excess speed first built up in the dive, quickly regain height and suddenly be sitting right behind the astonished enemy pilot."

Ok...

Situation - Enemy fighter on my six.
1. Climb steeply with half roll and kicking rudder.
2. My A/C will yawing 180 degree to backside.
3. Complete full roll.(I think in this situation, enemy and me in head on position.)
4. steep dive.
5. Pull up the A/C to 180 degree When excess speed built up.(Steep climbing?)
6. ???
7. Profit!!!

Am I understand it correctly?

 

[BiffF15]

Gomwolf,

It reads to me that he is snap rolling at the top of his initial climb, which I believe involves a hard roll with a stomp of the rudder, to make the aircraft yaw around it's longitudinal axis. The snap roll would scrub off a bunch of speed (overshooting your adversary). He would then dive to get his speed back and then get on the tail his opponent. Just my opine FWIW.

Cheers,
Biff

 

[gomwolf]

Gomwolf,

It reads to me that he is snap rolling at the top of his initial climb, which I believe involves a hard roll with a stomp of the rudder, to make the aircraft yaw around it's longitudinal axis. The snap roll would scrub off a bunch of speed (overshooting your adversary). He would then dive to get his speed back and then get on the tail his opponent. Just my opine FWIW.

Cheers,
Biff

Thanks for opinion. I agree about initial climb. It seems like snap roll or some kinds of hammerhead. I think I have to try it on flight sim game.

 

[Greyman]

Reminds me of an anecdote Arthur Bishop (Billy Bishop's son) wrote about George Beurling:

One one occasion, and one only, even though we were with different squadrons, I had the enviable experience of making a practice flight with George, who taught me a lesson that many months later probably saved my life. Over breakfast one morning, he asked, "Care to take a flip with me?"–an offer I couldn't refuse. With my commanding officer's permission, I rendezvoused with George at the end of the runway to take off for a tail-chase, a follow-the-leader exercise.

I was pretty excited because I prided myself that through much practice, I was able to stick to the leader through thick and thin no matter what manoeuvre he put me through. But I wasn't prepared for what George had in store.

For starters, I followed George through the usual procedures of slow rolls, loops, rolls of the top of the loop, twisting dives, spiral climbs, steep turns, and so on–no trouble at all. Then–suddenly, and when I least expected it–George pulled up sharply, cut his throttle, flicked around, zoomed past above me, rolled out, and ended up on my tail, all in a matter of seconds.

Over the radio, he laughed, "Got you, eh? That's a stunt that can get you out of a whole lot of trouble if a Hun gets up your ass," he said. "Follow me and I'll show you how to do it."

For the next twenty minutes, I clung to his tail like glue while George patiently put me through the paces. Varying the throttle thrust, spiralling, whipping from one side to the other, then climbing and twisting, George gradually increased the tempo each time. It was a tough routine. I was sweating, trying to stay in place, but finally I had the pattern pretty well down pat, and I later practised it diligently. But George cautioned me: "It won't do a bit of good unless you keep a sharp lookout. Keep turning your head–up, down, and sideways–so you wont get bounced by surprise." (An echo of what my father once told me ... )

 

[drgondog]

Great if the pursuer doesn't have a wingman.

 

[XBe02Drvr]

Thanks for opinion. I agree about initial climb. It seems like snap roll or some kinds of hammerhead. I think I have to try it on flight sim game.

Don't try it in a P-39 or P-63; you'll wind up in an inverted flat spin pinned in your seat and unable to get the door open.
Cheers,
Wes

 

[bobbysocks]

read somewhere that the 39s problems were because the CG changed when the cannon ammo was either full or empty. much like the fuse tank on the 51. once the ammo was depleted or until the ammo was used up the situation occurred. don't know how true that is but it does make some sense.

 

[XBe02Drvr]

With its aft-mounted engine and no correspondingly heavy weight forward, the P-39/63 aircrafts were noticeably susceptible to tail heaviness with its attendant instability. When the CG gets too close to the center of lift there's almost no stabilizing force driving the aircraft back towards equilibrium after it has been displaced in pitch. Stick force gradients are almost non-existent, so a mere twitch on the stick may result in an over stress or an accelerated stall in a positive or a negative direction depending on speed and G-load conditions.
The sequence of moves in Walter's nasty surprise are apt to accelerated stall your Airacobra in an asymmetric condition, whipping it into a spin where the your frantic effort to recover will over-control it into a negative asymmetric stall. (no stick force gradient, remember?) Once the rotation rate winds up your elevators are blanked by the wash from your rotating wings and fuselage and have no "bite" to break the stall. There you are, inverted flat spin, pinned in your seat watching the earth rise up to meet you. Your opponent goes home with his guns unfired and paints another white star below his cockpit.
Cheers,
Wes

 

[drgondog]

read somewhere that the 39s problems were because the CG changed when the cannon ammo was either full or empty. much like the fuse tank on the 51. once the ammo was depleted or until the ammo was used up the situation occurred. don't know how true that is but it does make some sense.

True - expending all the ammo in the P-39 nose caused the CG to travel nearly to the extreme aft position in the static margin envelope - very similar to a P-51B/C/D/K with a full 85 gallon fuselage tank aft of the cockpit. NAA didn't solve the problem until they moved the cg of the engine slightly forward, added 13" to the fuselage aft of the cockpit and reduced the fuselage tank from 85 to 55 gallons for the P-51H