Undo and STC

Danny Deger

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Mar 17, 2007, 2:38:03 PM3/17/07

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If you have an aircraft that has had an STC done to it, can you remove a
piece of equipment required by the STC and take the airplane back to the pre
STC condition?

Danny Deger

ji...@specsol.spam.sux.com

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Mar 17, 2007, 2:35:02 PM3/17/07

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> Danny Deger

If you mean remove everything involved in the STC, sure, why not?

If you mean one part of an STC, the airplane would then neither conform
to the STC nor the orignal certificate, so no, not without something
to justify it.

--
Jim Pennino

Remove .spam.sux to reply.

Bob Noel

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Mar 17, 2007, 3:24:41 PM3/17/07

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In article <45fc2783$0$28164$4c36...@roadrunner.com>,
"Danny Deger" <danny...@hotmail.com> wrote:

I hope so... I don't have the autogas STC anymore (became invalid when
convert the engine to 160hp).

--
Bob Noel
(gave up lookingn for a particular sig the lawyer will)

John

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Mar 19, 2007, 5:33:18 PM3/19/07

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You have to remove all of the equipment required by the STC and file
another Form 337 documenting the removal of said equipment and STC.
STC stands for supplemental type certificate and it modifies the
original type design of the aircraft. Unmodifying the aircraft is
another change to the type certificate. Removing only part of the STC
does not return the aircraft to the original certification. You
cannot remove an STC with a simple log book entry.

Slightly off topic but I see lots of aircraft that have had fairly
simple STCs installed like Zeftronics ACUs or Brackett air filters
where the STC and Form 337 was never filed by the installing agency.
This means that the aircraft is technically illegal and has been ever
since the STC was not filed.

John Dupre'

Bill Zaleski

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Mar 19, 2007, 5:53:28 PM3/19/07

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You do not need to file a Form 337 in order to completely remove an
STC and return an aircraft or engine to it's original type design. It
is NOT another Major Alteration to return a product to it's original
unaltered TC condition, and that's what a 337 is only for (Major
repair or Major Alteration). A simple logbook entry using the
approved data of the TC is the only required entry.

Bill A&P IA

Bill Denton

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Mar 19, 2007, 7:14:54 PM3/19/07

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While probably not relevant here, things are a little bit different when you
are dealing with aircraft that are to be flown by Sport Pilots.

Consider an aircraft that, as originally manufactured, would meet the Light
Sport Aircraft criteria. But it was STC'd in such a manner as to no longer
meet those criteria.

You cannot remove the STC's to restore the aircraft to its manufactured
state and fly it as a Light Sport Aircraft.

The Light Sport regulations required that the aircraft must have met the
criteria continuously from the time of manufacture...

"Bill Zaleski" <w...@instrumentratings.com> wrote in message
news:ff1uv2p63p6dpi7rm...@4ax.com...

John

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Mar 20, 2007, 8:27:44 AM3/20/07

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On Mar 19, 4:53 pm, Bill Zaleski <w...@instrumentratings.com> wrote:

> Bill A&P IA- Hide quoted text -
>
> - Show quoted text -

I used to thinkso and it is probably another case of different FSDOs
interpreting the regs in their own way but at our FSDO (EA 61) the
word is that since you altered they type design with an 337 you are
altering it again when the STC is removed and that requires another
337. They told us that without the 337 filed the FAA has no way of
knowing the proper status of an aircraft's certification.

John also an A&P IA