Hi Dennis,
To summarize that "lengthy discussion":
1. When your plane was flown to demonstrate conformance with its Type
Certificate before receiving an Airworthiness Certificate, the Spinner
was listed Equipment on the ERCO Equipment List which was kept as a
factory record unique to your airframe.
2. I believe the ERCO production drawings applicable to your serial
numbered coupe to be part of the "Type Certificate: incorporated by
reference in pertinent CAA/FAA regulations. In all such drawings
produced by ERCO (and subsequent Forneys, Alons and M10s) the
"certificated aircraft" is shown with a spinner. That is why specific
automotive type temperature and oil pressure gauges, etc., are "legal"
in the Ercoupe...because their use was part of the CAA/FAA drawing
review and approval process. I have provided Ed Burkhead with FAA
documentary references to post that I believe support this position.
Perhaps he will provide necessary link(s) reference.
3. Those who advocate that no spinner is required (or that a "skull
cap spinner is an OK substitution) dismiss production drawings as
having no regulatory effect. If that were true, it would not be
necessary for the CAA/FAA to review and approve each revision to them.
Because a spinner is clearly a fairing in function, therefore, to be
consistent, they must also advocate that it is "legal" to operate an
Ercoupe without the fairings between the wing root and the fuselage.
Good luck with that (and on collecting on insurance if the bird gets
bent in the process)!
4. Anyone can remove their spinner or substitute a "skull cap" type to
such extent as they have complete faith that the FAA (and their
insurance company) agree this to be a "minor modification" and it is
entered in the appropriate log book. I would not choose to risk
operating in such manner without submitting and gaining FAA approval of
a 337 (which, by definition, makes it a "major modification") in
advance.
If one or more loose screws a single backplate spinner suffered
progressive attachment failure in flight such that an unsecured spinner
is sufficiently freeremains loosely "captured" flopping around the
rotating prop I believe it within the realm of possibility that
resulting vibrations could either rip the engine mount/engine off the
fuselage or cause sufficient damage to the prop that such could result.
If a loose engine remains secured by cowl supports, grounding strap,
hoses, cables, etc., the pilot has a change of surviving a controllable
glide to earth. If the engine departs the plane, the concurrent change
in CG assures virtually NO chance of survival.
Regards,
William R. Bayne
.____|-(o)-|____.
(Copyright 2010)
--
On Jun 6, 2010, at 16:41, Hartmut Beil wrote:
Dennis.
We had a lengthily discussion about spinners a while ago.
The opinions differ. Some claim the airplane would not be airworthy
without the correct spinner on one extreme and others claim that
cooling will be effected by the lack of a spinner.
I can tell from personal experience that the spinner makes no
difference in cooling , nor was my airplane not airworthy anymore. At
least my mechanic had no problem with it and neither did I.
On my spinner, the backplate cracked and I had to wait for a new one.
Meanwhile I went flying.
There was no difference in speed, airplane handling or cooling.
Appearance suffered, but hey, that's only on the ground, the engine
not running. Not a big deal.
However, there must be a reason why the backplate of your spinner
fails repeatedly. Maybe it is not the right spinner after all?
Hartmut
From: Dennis
Sent: Sunday, June 06, 2010 10:21 PM
To: [email protected]
Subject: [ercoupe-tech] Prop Back Plate
I've had several members tell me that for the prop back plate to last
longer (on my 1946 415C), I need to install a front plate and then I
think I would need a new spinner, since the holes in the old spinner
will not work with the new front plate.
I think the only purpose of the back plate is to attach the spinner.
So, rather than spending $500-$600 for the front plate, back plate,
and spinner, I am considering running with no plates and no spinner.
Other than reducing speed slightly and not looking as good, is anyone
aware of other negatives of running with no prop plates and no
spinner?
Thanks, Dennis
