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Hello all.
My 2 cents to the model discussion.
I own 3330H, that came out of the factory as a
415-C.
It had been factory converted to a 415-C/D and
later the 415-E conversion was approved.
The factory conversion to a C/D was one way of Erco
to improve sales in 1947. How?
ERCO tried to analyze the selling points and
payload was one of them. So they tried to get the D Model approved in the new
normal category, maxing out the new weight limitations. With 1400 lbs the coupe
would stall earlier and the elevator had to be restricted to keep the design
stall proof. It had to be that way, cause without ruder pedals, ones the stall
becomes a spin, no rescue would be possible.
We all know the story - undesirable landing speeds made the 415-D not that marketing success as expected, so the next idea was to go back to the old TC with a payload of 1260 lbs. This was not that simple.
With the new additions of a stainless steel fire wall extension and all the other changes, the Coupes coming from the line were not the approved 415-Cs anymore, they were something else.
So they called them 415-CD.
Whether the Marketing for the CD had in mind that it could be registered under either Type Certificate is not clear. It could be, because the CD Model is no different than the D Model, except for the elevator adjustment. (S/N 4501 and up designated model 415-CD identical to model 415-C except for revised throttle and trim control, wide
We all know the story - undesirable landing speeds made the 415-D not that marketing success as expected, so the next idea was to go back to the old TC with a payload of 1260 lbs. This was not that simple.
With the new additions of a stainless steel fire wall extension and all the other changes, the Coupes coming from the line were not the approved 415-Cs anymore, they were something else.
So they called them 415-CD.
Whether the Marketing for the CD had in mind that it could be registered under either Type Certificate is not clear. It could be, because the CD Model is no different than the D Model, except for the elevator adjustment. (S/N 4501 and up designated model 415-CD identical to model 415-C except for revised throttle and trim control, wide
trim tab (1/3/8 in. chord) in accordance Erco
dwg. 415-22031, improved fuel venting system, revised nose gear oleo
strut,improved interior trim and installation of
stainless steel upper fuselage skin.)
So why went ERCO out and retrofitted a number of
Ercoupes that were already in Dealers hands, but not further sold yet? The
conversion did not give you more payload or anything else that you did not have
in a 415-C. The only visible change is the throttle control. I doubt that the
airliner style throttle was such a killer feature that Ercoupe buyers were
searching for.
My only explanation is that the 415-CD could have
been either way registered. Under both TCs.
And that's how it should be. All Ercoupe 415s are
pretty much alike.
The minor differences between the models that
justify different payloads or engines, can easily be changed on almost any
airframe.
That means that one type certificate would just be
enough. Most airspeeds don't change and engine/airframe changes are
minimal.
That certificate would list the model designator
and lists the necessary changes to fit into that model or category.
Example:
415-C - normal category - 1260 lb gross,
stall at 48MPH/
gross
415-C - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
(elevator restriction would have to be reduce to 11-12 degrees up for the C, CD, and D models to stay in the power on stall proof area)
415-C - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
(elevator restriction would have to be reduce to 11-12 degrees up for the C, CD, and D models to stay in the power on stall proof area)
415-CD - normal category - 1260 lb gross,
stall at 48MPH/ gross
415-CD - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
(elevator restriction would have to be reduce to 11-12 degrees up for the C, CD, and D models to stay in the power on stall proof area)
415-CD - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
(elevator restriction would have to be reduce to 11-12 degrees up for the C, CD, and D models to stay in the power on stall proof area)
415-D - normal category - 1400 lb gross,
stall at 56MPH/gross
415-D - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
(elevator restriction would have to be reduce to 11-12 degrees up for the C, CD, and D models to stay in the power on stall proof area)
415-D - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
(elevator restriction would have to be reduce to 11-12 degrees up for the C, CD, and D models to stay in the power on stall proof area)
415-E - normal category - 1400 lb gross,
stall at 56MPH/ gross
415-E - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
415-E - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
415-G - normal category - 1400 lb gross,
stall at 56MPH/gross
415-G - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
415-G - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
415-F1 - normal category - 1400 lb gross,
stall at 56MPH/ gross
415-F1 - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
415-F1 - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
415-F1a - normal category - 1450 lb gross,
stall at 58MPH/ gross
415-F1a - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
415-F1a - sport pilot category - 1320 lb gross, stall at 51MPH/ gross
All models would qualify for the sport pilot rule
when operated under those limitations.
The models stay the same, just the requirements
change.
But how everyone thinks these days is that a
certain model , certified under a certain category, has to stay in this category
and model designation, otherwise it is not model anymore and not
airworthy.
This is the error everybody is making and that's
why we are all in pain with the tiny changes we are trying to do.
So in my eyes , all Ercoupe 415s are pretty much
the same except for some minor details, I would not try to split hairs over
it.
Hartmut
----- Original Message -----
From: "Ed Burkhead" <[EMAIL PROTECTED]>
To: "A J DeMarzo" <[EMAIL PROTECTED]>;
"Coupe-Tech" <[email protected]>
Sent: Wednesday, March 02, 2005 6:46
PM
Subject: [COUPERS-TECH] D and CD model
history
>
>
>
> Al,
>
> Please permit me to disagree without digging through all the books.
>
> As I heard it, there was a lot of pressure to get an increase in the
> gross weight approved. The airplane structure was OK but the FAA was
> unhappy in their testing at 1400 lb., full power, full up elevator
> (with, according to Bill Bayne, an extra few degrees added during
> testing to allow for maintenance errors in the field so 13° + 3 or 4°
> for testing). So the FAA limited the D model to 9° of up travel. It
> went into production.
>
> With the 9° up travel, the stall speed / landing speed increased
> somewhat and became less desirable. After making something like 77 D
> models, the factory cranked the elevator back to 13° (with few, if any,
> other changes) and sold the planes as model 415-CD for a while.
>
> My memory tells me that the sales slowdown started in the fall of '46
> when the dealers and pipeline became filled and demand suddenly
> slackened.
>
> Your comment that CDs were C models recalled by the factory is something
> I don't remember seeing in any of my source documents. Could you let me
> know, please, where you learned this?
>
> By my old charts (Bill Bayne is making new ones), there were 77 415-D
> and 368 415-CD made. It's true that there were a lot of planes sitting
> around in the winter, spring and summer of '47. If any were 'converted'
> to be D or CD, they were serial numbered with D or CD series numbers.
>
> I'm looking forward to Bill Bayne's upcoming book even though I don't
> know which year (or decade) he'll publish it. He's been doing some
> seriously careful research as is shown in many of his answers here on
> the list.
>
> Ed Burkhead
> http://edburkhead.com/
> ed -at- edburkheadQQQ.com (change -at- and remove the QQQ)
>
> I know you believe you understand what you think I said, but I am not
> sure if you realize that what you heard is not what I meant. (Jim, AKA
> Midnight Plowboy)
>
>
> -----Original Message-----
> From: A J DeMarzo [mailto:[EMAIL PROTECTED]
> Sent: Sunday, February 27, 2005 7:05 AM
> To: [email protected]
> Subject: Re: [COUPERS-TECH] 1947 415 CD Data Plate
>
> ----[Please read http://ercoupers.com/disclaimer.htm before following
> any advice in this forum.]----
>
>
> Larry;
> The CD and D are two different animals, they are not the same. You're
> on
> the right track by saying they were converted at the factory, but not
> all of
> the required work was performed. The CD's were actually C's that were
> either recalled by the factory or were excess factory stock that had a
> few
> of the improvements done. Many were done by Ercoupe dealers in the
> field,
> too!
>
>
>
>
>
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>
>
>
>
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