An interesting discussion, with some cententious points. I’d like to add a few words on the P38 Lightning side of things.
Yes, the P38 always had contra-handed props but the protype had them handed inwards, whereas the production models had them handed outwards. For the reasons explained above, inward would have been ideal, however the XP38 suffered alot of elevator flutter problems and one of the factors contributing to it was deemed to be downwash from the inwardly handed props. (This didn’t actually cure the problem entirely, it was eventually cured by a re-design of the wing root fillets.)
Unfortunately, this meant that BOTH engines on the P38 were ‘critical’, and the type therefore had a relatively high single engine safety speed. There is an article by Stephen Grey in an old issue of Pilot where he stresses the importance of keeping the aircraft low on take-off to let the speed build up to the single engine safety speed, any slower and the only option in the event of an engine failure was to throttle back the good one and put the aircraft down straight ahead. This issue with both engines being critical might explain why the Model 322, the British Lightning, had props turning in the same direction- atleast one engine wouldn’t be critical.
As for the 322 being a ‘dog’, yes that’s often the view expressed. However, the A&AEE put together a pretty positive report on the type, and there don’t seem to have been any handling problems associated with prop-rotation. All in all, they seem to have felt it was a good aircraft, if a little lacking in high altitude performance. (This is based on an online discussion I had with a guy who had a copy of the original report.) The advent of the Mosquito and other types meant that the Lightning was left out in the cold.
Someone also mentioned the dive recovery flaps on the later P38’s. Yes, the Lightning accellerated damn quickly in a dive, but the key factor was the low critical mach number of the aerofoil. Basically, it was very easy to dive the aircraft into compressability, and the dive recovery flaps introduced from the J model onwards brought the centre of lift back toward the leading edge, aiding recovery. They weren’t ‘air brakes’ as such, which is what they’re often described as. The P47 could also dive like a brick, but there was no need for dive recovery flaps because the type’s aerofoil had a much higher critical mach number. So, the use of dive recovery flaps was a sign of the limitations on the P38’s aerofoil, rather than just a sign of outright high performance.
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