4.12m sneaky P-38 fm changes

[Fenrir]

Hi guys, just tested the 38 in QMB in a power dive from 7500m.

Whilst compressability (buffeting and heavy elevator effects) start at the requisite indicated airspeeds, the documented elevator ineffectiveness at this mach number is not apparent.

By all accounts in the prototype the elevators were at the focus point of shockwaves which made them useless and the aircraft would even begin to tuck under (start an outside loop) until denser air was reached and the Mach decrease. Given you were not a) going too fast and b) not going too steep at this point you could recover.

The new mach effects on the FM no longer appear to demonstrate this effect. Elevators, whilst still heavy, are effective and can be used to recover above the critical altitude. Similarly trim.

[horseback]

The P-38 prototype was a very different aircraft from the production aircraft. The earliest designs lacked the fillet between the wings and the fuselage/cockpit pod, and once those were installed the buffeting at high speeds was reduced somewhat, and as long as you followed the Do Not Exceed speeds at the designated altitudes, you were okay. Of course, at extreme altitudes the Lightning could exceed its DNE speed in level flight rather easily, which was the price you sometimes pay for being one of the first to get that high and that fast...

But all high performance aircraft of that era were subject to compression effects when they went past their critical Mach number--it's just that the P-38's number was a bit on the low side, due in part because the whole compression/critical Mach problem was not well understood when it was designed in the late 1930s.

In any case, if you could get the aircraft below 6200m or so before it broke, it would supposedly recover quite nicely in the thicker air.

cheers

horseback

[Cap'n Crunch]

Well, here's hoping those 4.13 changes will correct the combat flaps by increasing the flaps takeoff setting to 250 IAS. 10% flap isn't enough, the manual gives a 50% position for combat flap at 250. The current speed restriction on half flap sort of castrates it's high altitude maneuverability, in a big way.

[Woke Up Dead]

I tried some dives in QMB; the P-38 is definitely not a death-trap when diving steeply anymore, the 109 has also improved.

However, it appears that the 1941 MiG still suffers from heavy elevators at speeds above 500km/h. Am I wrong? If not, is this by design?