Dan, I believe the nine degree up elevator limit in the 1329 lb STC resulted from the same restriction in the conversion of the C Model to the D Model. The data for the 1320 lb STC was based on the data used for the C to D conversion. Thus the question becomes, "Why the restriction for the conversion of the C to the D?" I have heard several different reasons but I don't know if any of them are correct. For one reason or another the FAA required the restriction when the higher gross weight was approved. Many pilots seem to agree that the heavier plane might be in danger of stalling with too much full up elevator and, should that occur, a recovery might be difficult. However, I don't know if that has ever been proven by a flight test. Another factor that could be involved is the amount of weight the FAA wants as a buffer over the allowed gross weight so that someone who misfigures and is "slightly" over gross won't be at extreme risk. I have had the 1320 gross since it became available and find that the elevator restriction is not really a problem to me.
John Roach N 2427H Caliendo Dan wrote: > > > Can anyone explain the 9 degree limit with the 1320 lb STC? If you are > within > > CG limits, I don't see how the extra 60 lbs play a role in 13 degrees > of elevator. > > Dan Caliendo > Ercoupe Mach 0.14 > 3658H > > On Apr 21, 2009, at 3:50 PM, Daniel Arditi wrote: > >> >> >> >> Yes Ed, I know, and I told him. I really don't know why it is like that. >> I will measure the up travel as soon as I can just to see how much it >> moves upwards. I'm just telling you what he told me, but I did not >> measure that. >> >> Serial number is 4849 (Model 415-CD). >> >> Thanks ! >> Daniel >> >> ------------------------------------------------------------------------ >> *From:* Ed Burkhead <[email protected]> >> *To:* Daniel Arditi <[email protected]> >> *Sent:* Tuesday, April 21, 2009 4:44:49 PM >> *Subject:* RE: [ercoupe-tech] RPM Drop during Climb Out >> >> >> >> Daniel, >> >> >> >> If the elevator up travel on an Ercoupe or Aircoupe isn’t correctly >> restricted, the plane is illegal to fly. It is also unsafe to fly. >> If the elevator does not have the up travel limits, the aircraft can >> stall and may not be able to recover. >> >> >> >> The airfoil used on Coupes is efficient but it has bad stall >> behavior. It is only safe on a Coupe because of the elevator up >> travel limits which prevent a normal stall. >> >> >> >> The 415-C and 415-CD should have the limiter set to 13° up travel >> unless you have the 1320 lb. gross weight STC in which case the limit >> must be at 9° up travel. >> >> >> >> The 415-D must be set to 9° up travel. >> >> >> >> Any model after the “D” will have the “split” elevator (the elevator >> with the cut out section in the middle). Some C, CD and D models may >> have been upgraded to have this elevator. It should be set to allow >> 20° of up travel (and gives about the same elevator effect as the >> 415-C and CD have with 13° up travel, but with increased saf ety ). >> >> >> >> You haven’t yet told us what model and serial number your friend’s >> plane has. That would help us help you. >> >> >> >> Ed >> >> >> ------------------------------------------------------------------------ >> >> *From:* [email protected] >> [mailto:[email protected]] *On Behalf Of *Daniel Arditi >> *Sent:* Tuesday, April 21, 2009 1:45 PM >> *To:* [email protected] >> *Subject:* Re: [ercoupe-tech] RPM Drop during Climb Out >> >> >> >> >> >> Yes Ed, I agree with you. >> >> >> >> One thing I told to my friend is that I don´t like the idea of not >> having the limit in the upward elevator travel. This can allow the >> coupe to climb too steep, when in combination with the the C90 engine >> power and low weight (fabric covered wings, not metal covered). >> >> >> >> Thanks again for all the help and advice. >> >> >> >> Next time, when everything seem to be OK, I would suggest my friend >> not to climb so steep, at least at take of. >> >> >> >> Daniel >> >> ------------------------------------------------------------------------ >> >> *From:* Ed Burkhead <[email protected]> >> *To:* Daniel Arditi <[email protected]>; ety >> <[email protected]> >> *Sent:* Tuesday, April 21, 2009 2:54:23 PM >> *Subject:* RE: [ercoupe-tech] RPM Drop during Climb Out >> >> >> >> Daniel, >> >> >> >> As far as fuel feed to the engine during extremely steep climbs, one >> could say that there’s no “limit” on how steep a climb a Coupe can >> safely do. >> >> >> >> If you try to go too steep, the fuel won’t feed, the engine will lose >> power, the nose will drop and the engine will immediately regain >> power. That’s pretty safe unless you’re trying desperately to climb >> over trees or a mountain ridge.. >> >> >> >> There is a physical fuel-flow limit on how steeply the Coupe can >> climb, though, and it’s so steep it’s very rare to encounter it. >> >> >> >> Normally, your best climb just won’t be steep enough to have this >> problem as long as your elevator up travel is rigged the way it’s >> supposed to be and the center of gravity is within the allowed >> limits. Come to think of it, perhaps you should double-check those >> items. >> >> >> >> I would avoid any flying situations that */forced/* me >> to */need/* that steep of a climb. >> >> >> >> Ed >> >> >> >> >> >> >> > > ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/ercoupe-tech/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/ercoupe-tech/join (Yahoo! ID required) <*> To change settings via email: mailto:[email protected] mailto:[email protected] <*> To unsubscribe from this group, send an email to: [email protected] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
