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silver-eagle

silver-eagle

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~John
A couple of things come to mind for electronics. I was thinking of replacing my current BK (MODE C) transponder with a Garmin GTX330. I'm told I can output to a Garmin 496 for traffic (and weather). Knowing I am replacing equipment, would I be required to get a 337 or is it considered a minor alteration?
Second question, same line. Would it be a minor alteration adding a marine band radio or would a 337 be required?
The Avionics shop thinks so. I just don't want to get hurt on the ramp because I don't have the right documents.
Any references would be good.
 
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silver-eagle said:
A couple of things come to mind for electronics. I was thinking of replacing my current BK (MODE C) transponder with a Garmin GTX330. I'm told I can output to a G49 for traffic (and weather). Knowing I am replacing equipment, would I be required to get a 337 or is it considered a minor alteration?
Second question, same line. Would it be a minor alteration adding a marine band radio or would a 337 be required?
The Avionics shop thinks so. I just don't want to get hurt on the ramp because I don't have the right documents.
Any references would be good.
Click to expand...

For reasons I've never been able to comprehend, most avionics shops think a 337 is required for any electronics installation. But AFaIK there's no support for that assertion in the FARs.
 
There's no specific FAR involved, but the FAA wants to know how many airplanes have what equipment (helps them with planning for things like TIS, ADS-B, transponder capability, GPS usage, etc), so they require 337's on all avionics installations. This is written up in some AC out there. In addition, I'm pretty sure that the addition of a marine band radio would require a 337, and probably some sort of interference testing unless it's already approved for aircraft use. Again, I believe the need for that is in an AC regarding avionics installation. Your avionics shop should be familiar with the relevant documents.
 
You are likely to get as many opinions as you'll get responders on this subject.

A like-kind radio exchange (Narco Nav/Com for a King Nav/Com) generally hasn't required a 337, but some IA's file one anyway. Others don't. For a while, installing a GPS required a 337 because it wasn't "like kind". After all it was GPS, not VHF. As of a few months ago I understand that a GPS/Com is now considered "like-kind" for any other type of Nav/Com and no longer requires a 337. Installing anytihing in your aircraft that wasn't on the original equipment list would require a 337.

Unless your marine radio is approved for installation in aircraft, under several specific TSO's, it is unlikely that you'll get approval for the installation. Now if it sits on the passenger seat and plugs into the cigar lighter, well that's o.k. and doesn't require any documentation.
 
For marine radios in aircraft, there are plenty of aircraft with successful installations (CG Aux, Fish Spotters, Marine/Fisheries), so there are either marine radios approved for aircraft installations, or there are FSDOs that have blessed them in the past. Best bet is to work with an installer who's done it before.
 
To answer your question on both accounts YES a FAA Form 337 is required. And yes there is a FAR requirement in Part 21.31 because you are changing the type design and also in Part 43.13 and 43 Appendix A.

You have to ask if by changing something is it at least equal to its original or properly altered condition (with regard to aerodynamic function, structural strength, resistance to vibration and deterioration, and other qualities affecting airworthiness). If something is better than the original it is a alteration.

So to install the new equipment what is involved cutting wires, circuit protection, weight and balance, new placards, possible flight manual supplement. Any one of these would make this a major alteration. Your avionic shop is correct with their call. Beside you have to have approved data to install it and a FAA form with block 3 signed by a FAA Inspector becomes approved data. If it were a minor alteration you would only need acceptable data big difference between the two.

There is at least one AC's you may want to read AC 43.210 and the new FAA Order 8900.1 Vol 4 Chapter 9 available at MyFSIM on the web http://fsims.faa.gov/


Just one man’s opinion, but a correct one.
 
Given that Stache is an FAA Airworthiness Inspector who checks this stuff for a living, I'd go with what he said.
 
Ron Levy said:
Given that Stache is an FAA Airworthiness Inspector who checks this stuff for a living, I'd go with what he said.
Click to expand...

Ron,

I wasn't disagreeing - Merely pointing out the humor in his statement of a "right opinion."

However, since you are one of the people who constantly complains about differences between FSDO's and individual inspectors, I'm surprised to hear you say to take one's opinion as the absolute gospel.
 
flyingcheesehead said:
Ron,

I wasn't disagreeing - Merely pointing out the humor in his statement of a "right opinion."

However, since you are one of the people who constantly complains about differences between FSDO's and individual inspectors, I'm surprised to hear you say to take one's opinion as the absolute gospel.
Click to expand...
On this one, with the references he's posted, I'll take it as absolute gospel that you'll have trouble with the FSDO if you don't do it as he describes. BTW, his usual tag line is limited to "just one man's opinion," and I think he was making a point with the addition on this one.
 
flyingcheesehead said:
Ron... since you are one of the people who constantly complains about differences between FSDO's and individual inspectors, I'm surprised to hear you say to take one's opinion as the absolute gospel.
Click to expand...
No offense to Ron or Stache (it's great to have a qualified source here!), this is a good example of how different FSDO's, and airworthiness inspectors, interpret regs and operate their departments. Given a little time and resources, I can easily produce another certified FAA airworthiness inspector that will disagree with Stache.

I didn't make up my original posting. The information was told to me by an airworthiness inspector. As the saying goes, "The thing that's so great about standards are that there are so many of them."
 
Prior to my returning to flying, I went through no less than three different inspectors at the same FSDO. Their answers went from "Take the 709 ride, similar to a private pilot checkride, and you're good to go." to "You're completely revoked. You have to start over again." The funny thing is, the actual records of my situation were way up north and strictly on paper from the old days.

It finally took a Chicago regional counsel who obtained the physical paperwork, reviewed it then gave me his opinion of a correct answer... in writing!

It seems to me that if you want to do anything questionable with regard to airmen or aircraft, you just about have to get it clarified in writing for a CYA down the road; even if it's as simple as you submitting a written proposal and having at least one inspector approve it. Then, you've got that to fall back on at a later date should questions come up.

I did a similar act when I recreated times from a lost logbook based on my first 8710. It's signed by an inspector and notarized. I may never need it but I have it.
 
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