Conversion to a D requires the plane meet the 787 type certificate. 787 was certified under a different set of rules than 718 and the fire protection requirements differ slightly. Since this part does not in any way affect the flight characteristics, and since the STC does not remove the plane from TCDS 718, the stainless skin is not required.
John Cooper, A&P Skyport Services PO Box 249 4996 Delaware Tnpk Rensselaerville, NY 12147 518 797-3064 Fax 518 797-3865 www.skyportservices.net _____ From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Roy Stubbs Sent: Wednesday, November 07, 2007 2:38 PM To: [EMAIL PROTECTED]; mbpowell; [email protected] Subject: RE: {POSSIBLE_SPAM}: [PHI] RE: [ercoupe-tech] LSA Weight increase STC So years ago I considered changing my C to a D. Boy, now Im glad I did not! But there is at least one significant modification required to change from C to D that surely is not part of the 1320# STC, and that is the requirement to replace to skin over the center tank with stainless steel. It is part of the Univair mod kit. Roy _____ From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Ed Burkhead Sent: Wednesday, November 07, 2007 12:33 PM To: mbpowell; [email protected] Subject: {POSSIBLE_SPAM}: [PHI] RE: [ercoupe-tech] LSA Weight increase STC Importance: Low Mike, May I answer from the perspective of having flown around 800 hours in that configuration, much of it at a gross weight of very near 1320 lb., some of it at higher gross weights. 1. As I understand it, the STC requires that the same changes be made in the plane AS IF you were converting it to be a D model (though you are NOT converting it really to be a D). 2a. This includes changing the up elevator restriction from 13° up travel to 9° up travel. This elevator restriction changes the touchdown speed from the close ballpark of 50mph to the close ballpark of 55mph. YMMV. 2b. Side comment: If the runway is long enough, you can still land with touchdown at 50 mph by having the engine about 200 rpm above idle as you hold it off, hold it off, hold it off in the flare about 1-3 feet high and hold the nose about even with the far end landing lights. This slows down the sink rate, the air over the tail lets the tail push down farther getting you to a higher angle of attack and slower airspeed (50 mph) and almost guarantees a perfect squeak-squeak landing and compliments. It's the same technique used for night landings when you aren't absolutely sure just how far down it is to the runway. It's very gentle on the plane AS LONG AS YOU HAVE ENOUGH RUNWAY. 3. If you were really foolish, foolish enough to be 50' high with the nose pointed way down, that elevator restriction might make a difference in hitting nose first rather than pancaking onto the runway level. I don't recommend either. Fly the plane like you would any other plane, with normal airspeed cushion, and it lands just fine. I NEVER came anywhere close to such a situation in the hundreds of landings I made in this configuration. 4. On takeoff, you have a bit less up elevator authority to get you off of a very short or very soft field. But that only matters to get you off the ground, in my analysis. I don't think it'd make any big difference in your climb over a 50' obstacle. That's because, with the engine at full power, there's plenty of air over the 9° elevator to push the tail down and obtain the best angle of climb airspeed. More elevator would only push you BELOW the best angle of climb airspeed and thereby reduce your climb. 5. The structure of the plane is fundamentally the same whether you have the C, CD, D, E, G and even with the 1450 lb. gross weight Forney F-1A, Alon and Mooney models. The structural strength is not a problem at all. 6. To handle the heavier gross weights on landing, the increased gross weight STC (just like the change to model D) requires the earlier model Coupes to make some small modifications to the landing gear, changing orifice sizes in the shock and such, if I remember correctly. Summary: DO IT! It's a good change to get the increased gross weight. This is what's necessary to do it legally. (There are those who say these changes are not needed for safety and I won't argue with them but flying over legal gross can be bad for your ticket and insurance coverage.) JMHO. Ed Ed Burkhead http://edburkhead. <http://edburkhead.com> com East Peoria, Illinois ed -at- edburkhead???.com (change -at- to @ and remove "???")
