Replacement of a full skin with no splices, identical (or factory approved) rivets and spacing, and Identical or factory approved materials (in this case stainless) is a minor modification.
Bill A&P-IA To: [email protected] From: [email protected] Date: Thu, 30 Jul 2009 11:38:22 -0500 Subject: Re: [ercoupe-tech] stainless steel skin Hi Linda, Yes it is a safety issue big-time. When Fred Weick redesigned the cowling from his original model 415 (with ERCO inverted inline four cylinder power) to accept the much wider and higher-mounted Continental opposed-four, to properly fair the top and sides he had to extent it back over the fuselage from the firewall to the windscreen. At the time, no one realized that, in case of an engine compartment fire, there was no stainless steel "firewall" protection for the fuselage tank. Only a thin sheet of aluminum would separate the 5-6 gallons of fuel in the header tank (and souls on board) from such a fire. This was corrected on the later 415-D, CD and subsequent models. Unfortunately, the simple substitution of the stainless sheet for the aluminum sheet in production is much more expensive as a retrofit endeavor than simply adding a stainless covering to the existing aluminum with cherry rivets. The fire protection is identical but this process was never factory or FAA -approved as an option when converting a C to a D model. Since the 1320 lb. STC does not do this, and since the addition of such stainless protection is obviously desirable from a safety standpoint and does not in any manner adversely affect the structure of the upper forward fuselage it would be my humble opinion that addition of the stainless panel over the existing aluminum sheeting should be considered a "minor modification" and relatively simple to do within the existing regulatory framework, but I'm no mechanic. That said, nothing is "easy" anymore when dealing with the FAA unless you "know somebody". Regards, WRB -- On Jul 30, 2009, at 04:09, Linda Abrams wrote: > John, > > Someone else on the list wrote > "The stainless steel panel was not functional for the gross weight - > its > addition was regulatory to correct an error in the original C > certification." > > Do you think the stainless steel panel is a safety issue? I realize > that C models are not required to have it, but should we consider > adding it as a matter of safety? > > Linda > N3437H (Sky Sprite) > 415-C > L.A. > > 2a. Re: Model C or D; gross wt. STC > Posted by: "John Cooper" [email protected] > Date: Sat Jul 25, 2009 10:12 am ((PDT)) > > <snip> > The stainless steel skin is required on the model D and later because > of > differences between the regulations under which the C and CD are > certified > (CAR 4a Aircraft Specification A-718) and the D and later models were > certified under (CAR 3 Type Certificate Data Sheet A-787). Since > 415-C's > under the STC remain C's the stainless steel skin is not required. > (CD's > already have it). > > > John Cooper > Skyport Services > www.skyportservices.net > > > > > > > > > ------------------------------------ > > Yahoo! Groups Links > > > _________________________________________________________________ Windows Live™ Hotmail®: Search, add, and share the web’s latest sports videos. Check it out. http://www.windowslive.com/Online/Hotmail/Campaign/QuickAdd?ocid=TXT_TAGLM_WL_QA_HM_sports_videos_072009&cat=sports
