---------------------------------------------------------- Avionics-List Digest Archive --- Total Messages Posted Fri 08/11/06: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:24 AM - encoder approval () 2. 04:39 AM - encoder approval () ________________________________ Message 1 _____________________________________ Time: 04:24:47 AM PST US From: Subject: Avionics-List: encoder approval --> Avionics-List message posted by: 8/11/2006 Responding to an AeroElectric-List message previously posted by Kevin Horton. Hello Kevin, Time spent in attempting to correct an injustice or an absurdity by governments is never wasted. It is a peculiarity of human nature that once people are placed in a position of authority or officialdom that a percentage of them will abuse that position either out of ignorance or arrogance. Left unchallenged, that abuse never diminishes on its own, but instead tends to grow. The current situation is that every day companies are manufacturing and selling more non TSO'd encoders that are better than the TSO calls for, some builder are buying those encoders or have bought them in the past, avionics shops are approving those non TSO'd encoders in accordance with the tests called for in FAR Part 43 Appendix E and F, and many airplanes (hundreds? thousands?) are flying around with those encoders responding with an altitude readout that ATC is entirely satisfied with. And FAA headquarters currently says: "No, that can't be because it is in violation of FAR 91.217 (b) as we interpret it." I don't know how this situation would eventually resolve itself if we just ignored it, but I don't feel that a head-in-the-sand approach is the best way to go. OC -- The best investment we will ever make is in gathering knowledge. < Good luck. I think you are wasting your time, albeit for a good cause. Granted, you might manage to find some FSDO that doesn't understand that 95% probability does in fact mean over the full range of expected conditions (speaking from experience working with the aircraft cert FARs for many years). But, once Washington finds out the FSDO has approved something under 91.217(b) without requiring testing over the full range of conditions, they will probably release a policy letter that stops you in your tracks. I'm not saying that things should be like this, but this is the way they are, like it or not. The only way out, in my opinion, is a change to 91.217, but reg changes typically take 10 years or more. Kevin Horton>> ________________________________ Message 2 _____________________________________ Time: 04:39:12 AM PST US From: Subject: Avionics-List: encoder approval --> Avionics-List message posted by: 8/11/2006 Responding to an AeroElectric-List message previously posted by Brett Ferrell Hello Brett, Thanks for your input. In fact it was the EAA web site wording that caused me to take action on this issue. My reaction was: How can the EAA, which is supposed to be our amateur built proponent, ignore the current situation which is that every day companies are manufacturing and selling more non TSO'd encoders that are better than the TSO calls for, some builder are buying those encoders or have bought them in the past, avionics shops are approving those non TSO'd encoders in accordance with the tests called for in FAR Part 43 Appendix E and F, and many airplanes (hundreds? thousands?) are flying around with those encoders responding with an altitude readout that ATC is entirely satisfied with? When I corresponded with EAA on this issue their response was: "We stand by our position." I could not accept this head-in-the-sand approach and wrote to the FAA. OC -- The best investment we will ever make is in gathering knowledge. < Have you enlisted the help of EAA on this matter? I would think that thier involvement would be helpful. They've already weighed in on this matter, in the other direction, supposedly with FAA input!!.....skip.....>>