What is PMAed, STDed, etc.?

In researching after-market instrument lights (see:

http://groups.google.com/groups?hl=e....tagonline.com

), I've run up against some terms that I think I should understand better.
These are "STCed" and "PMAed". I understand that they're somehow related to
having these lights (or whatever is under discussion) approved for installation,
use, or some such in an aircraft. But I think I need to understand this better.

STC stands for "Supplemental Type Certificate". This "certifies" a
modification of an aircraft from its original design.

PMA stands for "Parts Manufacturer Approval". This is an approval of a
replacement part.

I don't quite have the "big picture". For example, the Nulite web site
indicates that all their products carry a PMA certification. Thus, again
according to the site, "any certified person" can make the appropriate log
book entry and the installation is "legal". That's right? Is "any
certified person" an I&A?

But I'd be using the Nulites not as a replacement for anything, but as
a new lighting solution. Does that make a difference? That is, does this
mean that a PMA is insufficient, and that an STC is required?

If not...when is an STC required instead of a PMA?

Thanks...

Andrew

A PMAed part or assembly is one that can be used as a direct replacement for
the original part or assembly. Whether or not the owner/operator can
legally install a PMAed part depends upon the type of part and whether its
replacement is within the bounds of allowed owner/operator maintenance as
defined in FAR 43.17(c). However, regardless of whether the PMAed part is
installed by the owner/operator or an A&P, it requires just a simple logbook
entry just like any other part replacement.

An STC introduces an alteration that was not covered by the airplane's
original type certificate. Installation of an STCed part or system must be
accomplished in accordance with the STC. This may be a major or minor
alteration, but as I understand it, it would in any case need to be signed
off by an A&P, and possibly an AI. In many cases a new weight and balance
would need to be calculated and recorded.

--
-Elliott Drucker

In article ,
wrote:

A PMAed part or assembly is one that can be used as a direct replacement
for
the original part or assembly. Whether or not the owner/operator can
legally install a PMAed part depends upon the type of part and whether
its
replacement is within the bounds of allowed owner/operator maintenance as
defined in FAR 43.17(c). However, regardless of whether the PMAed part
is
installed by the owner/operator or an A&P, it requires just a simple
logbook
entry just like any other part replacement.

An STC introduces an alteration that was not covered by the airplane's
original type certificate. Installation of an STCed part or system must
be
accomplished in accordance with the STC. This may be a major or minor
alteration, but as I understand it, it would in any case need to be
signed
off by an A&P, and possibly an AI. In many cases a new weight and
balance
would need to be calculated and recorded.

and the OP wrote:
But I'd be using the Nulites not as a replacement for anything,
but as a new lighting solution. Does that make a difference?
That is, does this mean that a PMA is insufficient, and that an
STC is required?

If the part is not PMA'd for your aircraft, you'll need a different
"basis" for the approval of the installation in your aircraft. This
does not need to be via an STC.

As an example, a digital OAT probe I installed in my cherokee
was PMA'd for certain beechcraft aircraft but not my cherokee.
The installation this digital OAT probe was approved via a 337.

good luck.

--
Bob Noel

I was told in A&P school that It stands for Parts Manufactured Approved.



Tim A&P PP-SEL IA
wrote in message
...
A PMAed part or assembly is one that can be used as a direct replacement
for
the original part or assembly. Whether or not the owner/operator can
legally install a PMAed part depends upon the type of part and whether its
replacement is within the bounds of allowed owner/operator maintenance as
defined in FAR 43.17(c). However, regardless of whether the PMAed part is
installed by the owner/operator or an A&P, it requires just a simple
logbook
entry just like any other part replacement.

An STC introduces an alteration that was not covered by the airplane's
original type certificate. Installation of an STCed part or system must
be
accomplished in accordance with the STC. This may be a major or minor
alteration, but as I understand it, it would in any case need to be signed
off by an A&P, and possibly an AI. In many cases a new weight and balance
would need to be calculated and recorded.

--
-Elliott Drucker

wrote in message ...

An STC introduces an alteration that was not covered by the airplane's
original type certificate. Installation of an STCed part or system must be
accomplished in accordance with the STC. This may be a major or minor
alteration, but as I understand it, it would in any case need to be signed
off by an A&P, and possibly an AI. In many cases a new weight and balance
would need to be calculated and recorded.

An IA must sign off the 337, which is required of any major alteration. An STC
provides authority to make the major alteration. A minor alteration requires
neither a 337 nor an STC.

"aptim" wrote in message ...
I was told in A&P school that It stands for Parts Manufactured Approved.

Parts Manufacturer Approval.

Aircraft manufacturers publish parts manuals for the airplanes they
build. The law says that you must use the parts specified in the
manual when replacing things. If the part has an industry-standard
number, like an AN bolt or fitting or wheel bearing, you can buy it
from any aircraft parts supplier.
If the number is a proprietary number (invented by and belonging to
the airplane manufacturer), such as a throttle control cable, the
requirement to use only that part means that you have to buy it from
the airplane dealer. The manufacturers are inclined to take advantage
of this and we see some ridiculous prices.
The PMA (Parts Manufacturer Approval) provision relieves us of
some of the robbery. McFarlane Aviation, for example, manufactures
engine control cables, seat parts, hinges, and a lot of other common
stuff that fits common airplanes, and their prices are much more
reasonable. Their numbers are the original proprietary number with an
identifying prefix added to it to avoid the copyright mess on the
original part numbers, while still qualifying as meeting the parts
manual requirements. Their competition often forces airframe
manufacturers to lower their prices, and some of the stuff they build
is actually better or stronger, such as the McFarlane Cessna seat
rails and roller washers.
It's still wise to shop around. Sometimes the dealer's OEM prices
are better than the PMAd stuff.

Dan

Nope. Parts Manufacturing Approval

Jim


"Ron Natalie"
shared these priceless pearls of wisdom:

-
-"aptim" wrote in message
...
- I was told in A&P school that It stands for Parts Manufactured Approved.
-
-Parts Manufacturer Approval.
-
-


Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

"Jim Weir" wrote in message ...
Nope. Parts Manufacturing Approval

"Ron Natalie"
shared these priceless pearls of wisdom:
-Parts Manufacturer Approval.

Sorry, Jim. I disagree. While the FAA abuses the term term as "manufacturing"
in a few advisory circulars. The term is "manufacturer" in both the FAR (Part 21,
subpart K) and in order 8110.42A (the PMA process itself).

Ron Natalie wrote:

An IA must sign off the 337, which is required of any major alteration.
An STC
provides authority to make the major alteration. A minor alteration
requires neither a 337 nor an STC.

It sounds from the above like an STC is required before any major alteration
because it "provides authority to make the major alteration". Is that
right?

A lot seems to hinge on the distinction between "major" and "minor"
alterations. What is the difference? Given a particular change (ie.
replacing a panel overlay, or adding instrument lights), how does one know
into which category the change falls?

- Andrew