Hi John R.,
Appreciate the link to the 1320 lb. STC.
Sorry for delay...problems upgrading computer affecting internet access.
Having now read the wording of the STC I believe the "burden of
proof" would fall on anyone arguing for installation of these
baffles. Accordingly, I agree with previous opinions offered that
the C-85 baffles are not required by this STC when applied to an
Ercoupe with 85 HP.
That said, the case seems clear that any 415-E or G Ercoupe operating
without these baffles runs the risk of airworthiness questions.
Regards,
WRB
--
Begin forwarded message:
From: William R. Bayne <[email protected]>
Date: August 27, 2010 19:49:44 CDT
To: [email protected]
Subject: Re: [ercoupe-tech] cooling baffles diagram
Reply-To: [email protected]
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
