P38 Performance

[GScholz]

... the shaking and loss of control is sufficient for AH needs.

Whereas in real life the aircraft would "tuck under" and go into a vertical, sometimes even slightly inverted dive in the opposite direction.

[FLS]

I used auto pilot, which only controls trim IIRC.

So compressibility effects are not really modeled in AH?

You used the auto pilot mode that maintains your dive angle and your dive angle didn't change. That sounds right. You might want to try a manual trim for level cruise.

[colmbo]

I used auto pilot, which only controls trim IIRC.

So compressibility effects are not really modeled in AH?

If you used auto pilot, Im assuming auto-angle, it would have cancelled any pitch down from mach tach.  I suggest manually trimming for the dive then "freeze" the stick and watch for pitching.

No idea if they are or not, just "think" they probably aren't other than the shaking and control loss we see.

[GScholz]

No it wouldn't. Mach tucking was not correctable by using the controls. That's why it was a problem in the first place.

Mach tuck should start at M .68 in the P-38, but somehow it can stay perfectly controllable (though heavy on the controls) at M .72 or more, even without using the dive flaps. This gives the P-38 a capability it never had in real life, and I can only assume it's the same with the P-47. High altitude combat in AH scenarios then become anything but historically correct.

[FLS]

No it wouldn't. Mach tucking was not correctable by using the controls. That's why it was a problem in the first place.

Mach tuck should start at M .68 in the P-38, but somehow it can stay perfectly controllable (though heavy on the controls) at M .72 or more, even without using the dive flaps. This gives the P-38 a capability it never had in real life, and I can only assume it's the same with the P-47. High altitude combat in AH scenarios then become anything but historically correct.

What you did show is that the auto angle mode isn't historically correct.

[GScholz]

The auto pilot in AH only controls trim input. It doesn't even have enough authority to prevent the 109K from drifting off course in a WEP climb.

Go test it yourself in you don't believe me. Take a P-38 above M .68 and test it. I bet if you turn off combat trim and trim neutral before diving it will even pull out of the dive by itself, rather than tuck under like it should.

[Randy1]

No it wouldn't. Mach tucking was not correctable by using the controls. That's why it was a problem in the first place.

Mach tuck should start at M .68 in the P-38, but somehow it can stay perfectly controllable (though heavy on the controls) at M .72 or more, even without using the dive flaps. This gives the P-38 a capability it never had in real life, and I can only assume it's the same with the P-47. High altitude combat in AH scenarios then become anything but historically correct.

Keep in mind at subsonic speeds there may be no boundary layer disturbance behind the open dive flap.  When separation occurs the change down wash angle is unknown at least to us.  HTC may have the information and it may be modeled.

[FLS]

The auto pilot in AH only controls trim input. It doesn't even have enough authority to prevent the 109K from drifting off course in a WEP climb.

Go test it yourself in you don't believe me. Take a P-38 above M .68 and test it. I bet if you turn off combat trim and trim neutral before diving it will even pull out of the dive by itself, rather than tuck under like it should.

That sounds like the test you should have done.   

[colmbo]

The auto pilot in AH only controls trim input. It doesn't even have enough authority to prevent the 109K from drifting off course in a WEP climb.

Go test it yourself in you don't believe me. Take a P-38 above M .68 and test it. I bet if you turn off combat trim and trim neutral before diving it will even pull out of the dive by itself, rather than tuck under like it should.

I was doing some dives this morning in the P-38.  I established desired dive angle, hit auto angle to trim for that angle then turned auto OFF.  It held the angle fine all the way up to loss of control authority.  The dives I did started at 20K.

[FLS]

If you load the TA terrain for offline you can spawn at 30k from one of the fields. Makes for easier testing. Diving from 20k you get into the denser air too soon.

[colmbo]

If you load the TA terrain for offline you can spawn at 30k from one of the fields. Makes for easier testing. Diving from 20k you get into the denser air too soon.

Yeah, I was using the TA terrain but only found a 20K field/air start.

[GScholz]

Keep in mind at subsonic speeds there may be no boundary layer disturbance behind the open dive flap.  When separation occurs the change down wash angle is unknown at least to us.  HTC may have the information and it may be modeled.

Localized supersonic airflow starts occurring at M .68 in the P-38. The real one that is. I was passing M .72 in the cartoon one and experienced no adverse effects beyond control stiffness and screen shaking.

[FLS]

Yeah, I was using the TA terrain but only found a 20K field/air start.

It's field number A3,  it's not Bishop by default. It's NW of  A1 and the SE spawn is 30k over A1.