In this game, you can extend the gear up to about 300 knots in the F4U. This effectively replicates the actual use of a partial lowering of the gear selector in the cockpit which only dropped the gear doors which were used as a brake. But as with all aircraft, you have speed limitations on this in real life or the doors rip off or get jammed. So it works out just fine. Only problem is, it's easier to notice when a corsair is braking 'cause the gear is fully out, but I'm not sure why anyone would want to slow down in a Hog in the MA.