For what it is worth, I am a Mechanical engineer and have worked with structural engineers all of my life. Whenever I needed to route pipe, conduit or whatever, the structural engineers would allow holes in the structural members(I beams or whatever). I have seen some beams that looked like swiss cheese. If the holes are not over a certain size and if they are placed properly the integrety of the beam is not compromised. IT just has to engineered! As far as the breaking point being at a hole, that is normal. If a structure is loaded past its limit it will break. If there is a hole or a deep scratch near that point it will take the path of least resistance and go to the hole or scratch. That does not mean the hole was the cause of the break... An aeronautical engineer needs to analize the situation to determine the effect of the holes... Bob
--- On Tue, 9/22/09, Hartmut Beil <[email protected]> wrote: From: Hartmut Beil <[email protected]> Subject: RE: [ercoupe-tech] Re: Approved holes? To: [email protected], "Techlist Ercoupe" <[email protected]> Date: Tuesday, September 22, 2009, 10:36 AM Ed Yes I pointed out before that the Alons have holes drilled for the bucket seat installation. That's why holes per se seem not be the problem. But it would be up to UNIVAIR to pull out the engineering data to proof that to the FAA and at the same time give an evaluation when holes are ok and when not. I don't see that happening. What I see happening is that all 415 Spars with not approved holes will be damned to be replaced. Is anyone having a 337 that shows holes drilled into the spar cap for seat installation? The only 337 I have on file does that not. http://www.ercoupe. info/?n=Main. CessnaSeats Hartmut To: ercoupe-tech@ yahoogroups. com From: ebengui...@aol. com Date: Tue, 22 Sep 2009 08:42:11 -0400 Subject: [ercoupe-tech] Re: Approved holes? Morning All Regarding holes in spar cap: Alons basically have the same wing spar as the Coupe. Without going into nomenclature details, Alons have approximately 16 holes on the spar cap to accept seat brackets. Does anyone know of any problems with Alons falling apart because of these approved holes? Ed check out the rest of the Windows Live™. More than mail–Windows Live™ goes way beyond your inbox. More than messages
