Harry's statement is right on. This is a question I personally asked Fred Weick. He gave me the same answer as Harry details. As Fred described it to me, at 1400 lbs gross, full power and full up elevator at 13 degrees, the slipstream can force the tail down enough to get the wings to or near to a stall -- enough that the CAA said the plane could not be certified at that weight. With all these conditions and 9 degree up travel, it gets squirly but stays controllable.
Practically, my 415-D lands at about 50, maybe plus a hint. I've heard but can't document that the change in touchdown speed is about 5 mph. With all these conditions and 9 degree up travel, it gets squirly but stays controllable. Since my plane has rudder pedals, I've done the max power thing with coordinated rudder (like a two control Coupe) all the way up to full power. I've also tested it up to 2300 rpm with the controls crossed and it stayed controllable __but__ it was unstable enough I did NOT do cross controlled tests all the way up to max power. Personally, in my opinion, I would prefer to not ride in a model C Coupe at 1400 lbs gross. I think it's better to do the D conversion. Better yet is to do the D conversion then do the split-elevator conversion which gives better control in all conditions. -- Ed Burkhead East Peoria, Ill. N3802H, 415-D -------------------- Harry Francis wrote: Yes, Spike, I feel certain that there was considerable flight testing done to ascertain flight characteristics of the 1400 gross certification.. Weick (I believe) stated that the CAA (FAA) required tests at excessive rear CGs to assure safety, and confirm the coupe was not stallable or spinable, and even still controlable at rear CG limits. ( I find it interesting that the Ercoupe is still controlable if you lose the metal prop - or so it seems). With 1400 lbs. and 13 degrees up travel, and power on, the coupe was able to completely stall. With 9 degrees it wasn't able to attain the necessary angle of attack to attain a stalled condition. With power off, the 9 degrees wasn't satisfactory because of landing attitude was too flat. That is why Ercoupe introduced the CD model ( going bacvk to 1260 # gross. Later, when the split elevator was introduced, the prop wash had less effect on the elevator, so that with full power, the increased "up elevator of 20 degrees" gave satisfactory engine off control, but did not raise the nose too high with power on. (Note this has nothing to do with 85 HP, but with angle of attack at specific loads..and gross weights).
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