The extra 15 deg doesn't lower the stall speed on PA 31's. The diff between flaps up and full flap is only about 4 kts anyway. The difference between having 25 deg and 40 deg is via a piper modification, that was required to overcome an assymetric flap problem that appeared. All PA 31's have the ability to apply 40 deg of flap, it's just that unless the AD's are accomplished, the flaps are required to be mechanically limited to 25 deg, which allows some control of the aircraft in that situation. And it is marginal control at that, hence the max of 25 deg. The differences in speeds etcetera wing lockers and sans winglockers are due to drag considerations and single engine speeds I think. Welcome back to 'em, they not that bad..............
While we're at it check the VG kit manufacturers AFM supplement. If you get to fly the -350, MCP goes from full throttle and 2575 RPM, to 40" and 2400 RPM. The old MCP has a 5 minute limit applied to it after fitment of the kit. Dunno if it affects the -310 tho.
Last edited by Dale Harris; 2nd July 2002 at 10:37.