The International Cessna^® 170 Association

I bought a new UMC tach for my C-170. It is TSO'd but not STC'd. Has anyone done a 337 field approval on this tach on any airpIane? I would appreciate any info you can give me. It's a great tach and works exceedingly well. If you're not familiar with it it has a standard face but is run electroncally rather than mechanically. Thanks.

There are some who will argue with this but.... there is no requirement that a TSO'd tach be STC'd for a particular aircraft.

George,

That's what my AI thought as well but apparently the FAA, where this tach is produced, wants a 337 field approval done. The factory called me and asked if I had one so they could show the FAA that there was a field approval somewhere in the US. I hate to call the FAA here and just stir up something that may not have to be stirred up.

Thanks.

N2782C wrote:George,

That's what my AI thought as well but apparently the FAA, where this tach is produced, wants a 337 field approval done. The factory called me and asked if I had one so they could show the FAA that there was a field approval somewhere in the US. I hate to call the FAA here and just stir up something that may not have to be stirred up.

Thanks.

Experience tells us that if you're not in the region where a particular FSDO has a certain opinion.... then their opinion doesn't count in your region. (Witness the rear-seat-removal issues discussed previously here in the forums. As has been pointed out by one of our own FAA-participants, the onus would be upon them to prove it.) I'd not have any qualms about it if my IA didn't.

I have no qualms....thanks.