My thanks to all who replied on the altimeter issue, especially Harry Francis for including the copy of Joe Norris's letter. You've all been a great help! I just hung up the phone with Joe Norris (EAA) who put it even more simply than before: PROVIDED you're NOT flying IFR, the ONLY panel instrument for which we're advised that VFR-only Ercoupes do want/need to get TSO'd equipment is our encoding transponder (and that's only because the reg says it must "meet the standards of TSO'd" and the easiest way to do that is just get the TSO'd one). This comment is limited to Ercoupes (our A-718 Type Certificates don't even mention altimeters), and expressly limited to flying ONLY VFR. This was as far as my inquiry needed to go; please don't consider it applicable to any other aircraft or to IFR flight without further checking which I didn't do.
Also, Jose wrote to me off-list and I'll paste his very helpful note below. I did phone Naylor's as he suggested, and found them very courteous, helpful & informative. I was considering an eBay altimeter that Naylor's had certified, and I learned from Naylor's that certification just tells you that it was tested within mfgr. specs on a certain day & time. It does not imply that Naylor's did the rebuild/overhaul (they hadn't in this case), and it carries no warranty. I also learned that different manufacturers have different acceptable margins of error at different altitudes. If Naylor's DOES go beyond testing and do the overhaul/repair, they give you a 1 yr. warranty. One last interesting note: SkyWest had insisted that the static port plumbing be extended from my airspeed indicator (where it has been) onward to the altimeter and other instruments (at $159.) Joe Norris said that *sometimes* having the system open to the atmosphere of our Ercoupes, rather than plumbed to static, results in *less* error, or in a case where there is some observed error, removing it from the static port plumbing may correct itself. He suggested trying it, and then using whichever way gives you a reading more in line with what altitude ATC says you're at. Counter-intuitive, but interesting... Linda N3437H (Sky Sprite) 1946 415-C L.A. Linda, New altimeters run about $700.00 I found a shop in Gainesville, Florida that is reasonable and very knowledgable. They can overhaul your unit for maximum costs of $225.00 Give them a call. 1-877-374-8160. Email: [email protected] Naylor's Instrument Service 4323 NW 6th Street Suite 5 Gainesville, FL 32609 Jose
