Hi Don,
As you know, you already have a trim function BUT someone, not necessarily wiser OR smarter than the Ercoupe owner paying the bills, had sufficient authority to decide that installation of the movable trim tab was part of the "price" to be paid to say one "had" 85 hp. I, too, fail to see any credible reason or logic behind this otherwise arbitrary requirement, but the CAA/FAA has no obligation to be logical, reasonable or even fair in it's exercise of duties largely self-defined and self-enforced. While the Ercoupe flies just fine with 85 hp and no separate trim tab, in case of an accident the question could be raised by both the FAA and any insuror as to whether said Ercoupe "conformed" to TC 718 so as to be "airworthy". If either takes the position that it wasn't the pilot is the one in "deep yogurt" holding the burden of proof that it was. Good luck with that ;<) So, as much as it pains me to say so, the lack of credible reason to make a required modification or the many safe hours of past operation without such clearly unnecessary modification means absolutely nothing if a flight has an unexpected ending. You (and your heirs) can wind up being handed a financial burden far in excess of begrudging compliance. Ercoupe Service Bulletin No. 38 is very specific that installation of the "new" trim tab system requires replacement of the old elevator with the new type. That said, I see no reason whatsoever that a confident mechanic could propose to a cooperative FSDO (presuming such to exist) a 337 to simply add the tab to the existing elevator. Yes, elevator area is increased, but the amount of increase is by an extremely minor percentage that would likely have no measurable effect on flight characteristics. If a reasonable flight test program could be agreed to demonstrate that, rigged as the "standard setup", the power off and power on results are identical there should be no reason whatsoever that such a 337 should not be approved. On the other hand, there is no incentive whatsoever for a non- engineer bureaucrat to take it upon themselves to sign such approval. These federal employees that no longer have ho hold an engineering degree never got paid any less of our tax money, so I believe it is factually accurate to bitch that the taxpayer thusly once again gets less service than was once delivered for their tax money. Now aircraft owners must hire and pay a DER to do what once was a responsibility and obligation performed with a measure of pride by these federal employees. This is one of a number of reasons that prompts me to publicly comment "I wouldn't mind paying taxes so much if the money went to a friendly government". But I DO pay them, however reluctantly, and on time. The penalties for not doing so are simply too much to accept. Regards, WRB -- On Aug 29, 2010, at 16:19, Donald wrote: > > > - > I suppose someone smarter than I decided upon it, but I fail to see > why the additional 10 hp requires a trim tab. I sure have not > missed having one so far, and am reluctant to install one.. > > > > -- In [email protected], iflysmo...@... wrote: >> >> Hey Don: The way to determine what is required is to read the type >> certificate/installation instructions. Item 110 of the type >> certificate states: >> 110. Engines >> Continental C-85-12 or -12F >> Engine limits for all operations: 2575 r.p.m. (85 hp.) >> (Eligible with item 1(c), 3, 4, 6, 7, or 8 propeller only). >> Eligible on model 415-CD; eligible on model 415-C provided the >> following >> are accomplished: >> (a) Modifications specified under item 106 for installation of >> C-75 engine. >> (b) Wide elevator trim tab (1-3/8 in chord) installed per Erco dwg. >> 415-22031 or narrow trim tab (3/4 in. chord) installed per >> Erco dwg. 415-22027 (or item 401). >> Note: Conversion of continental C-75 engine to C-85 must be >> accomplished in accordance with Continental Service Bulletin M47-16, >> dated 6-7-48 and the oil sump dip stick recalibrated to indicate >> full when >> >> So I think it is clear that the trim tab be installed. >> However, it >> does not have to be the wide (1-3/8 in. chord) that is required >> when you >> convert a C model to a D model. >> Lynn Nelsen >> >> >> In a message dated 8/28/2010 10:57:57 P.M. Eastern Daylight Time, >> dongen...@... writes: >> >> >> >> >> >> >> This is very confusing to me. I have a C75 upgraded to C85. My >> plane came >> with the extra oil tank and carb baffles NOT INSTALLED. I have >> been under >> the impression I was not correct until I installed them (although >> it has >> been flown for years with them in a box in the hangar. Am I >> reading this that >> there is no requirement to add those baffles on my 415C model? I >> am also of >> the belief that I must add a trim tab system to fully be in >> compliance with >> the C85 conversion (again it has flown for years that way without >> the trim >> tab, mine is an early model that came without a trim tab) >> >> --- In [email protected]_ (mailto:ercoupe- >> [email protected]) >> , "Kevin" <kgassert@> wrote: >>> >>> For the 1320 STC the aircraft must be in compliant with A-718 so >> therefore no additional cooling baffles needed. >>> >>> Kevin1 >>> >>> >>> >>> --- In [email protected]_ >> (mailto:[email protected]) , William R. Bayne >> <ercoguru@> wrote: >>>> >>>> >>>> The question (as I interpret it) seems an important one inasmuch as >>>> the answer essentially addresses the "airworthiness" of a given >>>> Ercoupe, with or without said baffles. Always remember I'm NOT a >>>> mechanic...I do have considerable engineering and legal experience >>>> reading and interpreting applicable specifications necessary to >>>> the >>>> supervision and inspection of installations by others. >>>> >>>> As previously stated here, there are NO special cooling baffles >>>> involved with a 415-C, or 415-CD with a 75 hp engine. >>>> >>>> If one upgrades the original C-75 to C-85 spec. for operation >>>> at the >>>> 1400 lb. gross wt. of the 415-D under Type Certificate 787, >>>> then the >>>> extra cooling baffles around the oil tank shown in the Ercoupe >>>> Parts >>>> Manual, Fig. 17, Items 13, 14 & 15 are required (as explained >>>> in the >>>> description of these items on p. 23). >>>> >>>> Since the 1320 lb. STC was approved using data from the 415-D >>>> Model >>>> under TC 787, logic would seem to dictate that flight >>>> operations at >>>> the higher weight would require the extra cooling baffles that are >>>> required on the 415-D when a C-85 is fitted. >>>> >>>> I seem to recall someone knowledgeable having previously commented >>>> that there was no actual flight testing associated with the review >>>> and approval of said STC. It may be that the actual wording of the >>>> STC paperwork does not specifically require the installation of >>>> these >>>> baffles (I don't have a copy for reference, but would appreciate a >>>> copy if anyone has the time and the inclination ;<). >>>> >>>> It is likely demonstrable that at 1320 lbs. with "standard day" >>>> conditions the extra baffles are not necessary to meet applicable >>>> cooling criteria, but that's a potential financial mine field in >>>> today's regulatory climate probably best not entered. >>>> >>>> Hope this helps, >>>> >>>> WRB >>>> >>>> -- >>>> >>>> >>>> On Aug 27, 2010, at 16:05, Ronin Sensei wrote: >>>> >>>>> >>>>> >>>>> >>>>> >>>>> Can anybody direct me to, or send me, a detailed diagram and >>>>> instructions for installing the cooling baffles on a 1320 lb >>>>> Coupe? (or a D model, since they are the same, I understand). >>>>> This is driving my A&P crazy. >>>>> Any help will be appreciated. >>>>> Dave Winters >>>> >>> >> > > > > > ------------------------------------ > > Yahoo! Groups Links > > >
