Paul,
It is legal to install anything in an experiential. However with
transponders they must meet the TSO requirements if they are to be
turned on. Doesn’t matter what type of aircraft. TSO required for all
aircraft and all airspce.
Just wish the certification would get done on the Trig 21.
Mark Mahan
2K


§ 91.215 ATC transponder and altitude reporting equipment and use.
(a) All airspace: U.S.-registered civil aircraft. For operations not
conducted under part 121 or 135 of this chapter, ATC transponder
equipment installed must meet the performance and environmental
requirements of any class of TSO-C74b (Mode A) or any class of TSO-
C74c (Mode A with altitude reporting capability) as appropriate, or
the appropriate class of TSO-C112 (Mode S).








On Jul 2, 4:07*pm, "Tim Mara" wrote:

a transponder has to be approved before it can get involved in the US ATC
system....otherwise we'd be using home made toys to mingel with airliners
and fighter jets...the controllers wouldn't appreciate this....but lawyers
might
tim

"Paul Remde" wrote in message

...

Hi,

I am looking forward to selling the Trig TT21 transponder in the USA once
they receive approval from the FAA (or whomever they need approvals from).
However, I just talked to someone who told me that his avionics person
said he could install one in his experimental aircraft - now - even though
the unit is not approved for use in the USA. *Can that be true? * I don't
think it is, but I'm not certain. *I would think it would be illegal to
use it in the USA until it receives US approvals.

Best Regards,

Paul Remde
Cumulus Soaring, Inc.

This may be a "meets requirements of TSO..." situation. And if so one
gate to this is *finding an approved technician who will sign off on
the required tests. See FAR 93.413 (c) 1. As an owner of an
experimental glider you do not get to
sign off on those yourself. So personally I would start by explain the
situation and ask a local installer/avionics guy if he can/is willing
to do this.

Darryl
Darryl

BTW I forgot, the "meets requirements" part is in FAR 91.215

The main relevant TSO is C112 (Mode-S) which traces back to RTCA/
DO-181 standards. The European
ETSO 2C112b traces back to EUROCAE ED-73B stabndards. I might have the
latest subversions of the standards wrong.

There can be subtle differences between EUROCAE and RTCA compliance so
you can just assume they are exactly the same. The question again
still is would a technician doing the post-install tests be willing to
sign off on a transponder that "meets requirements of TSO C112" and
how would they determine that?

I am not defending this or suggesting trying to do it. Just clarifying
what I think the situation is. If somebody disagrees please mention
the relevant FARs.

I'd still love to get to play with a Trig TT21.

Darryl- Hide quoted text -

- Show quoted text -