The STC has been accomplished with a model list, which I'm sure includes the Twin Commanche. A 337 is still required if you want to install it for IFR (not sure about a VFR installation). The FSDO will also approve your Flight Manual Supplement for the 430 which is specific to your airplane and equipment interfaced with the 430. Hope this helps.
A little over 2 years ago there was a new interpretation of the installation of certain GPS units. It deemed the installation of an approved GPS into a certified aircraft (on the list of those that it has been installed in and proven to work) to be a minor alteration. This same new interpretation also allowed them to be used for IFR without doing the "stupid" tests to see if it works in yet another common airplane. It always works...
337s are not so bad... BUT- My Garmin 530 (along with a 106C, 340, 330...) was installed on a logbook entry and a W&B recalc.
If you want the reg I'd have to get it for you out of my logbook.
I would love to know how to install this thing without a 337 so me and my A&P could get started on it this week... According to his avionics friend of his, a 337 must be done and could take a week or two of processing or somthing like that. I think the guy just wants us to use him for help so we by things from him. ( I will be using a KI-106 instead of a GI106, will this make a difference?)
If there is any way you can detail what i need to do for this install it would help me out SOO much.
My avionics shop gave me the same information as flyguydon has posted.....to the best of my knowledge a standard 430/530 in a certified aircraft is approved for IFR with just the routine logbook entries from the avionics shop. All the special paperwork, POH amendments, test flight, etc is no longer required for IFR. Make sure you get up to date information before spending a ton of money on paperwork.
I confirm that no supplemental 337 is required to install the Garmin. I had mine put into a Warrior in December, and when I flew away from the avionics shop it was fully IFR certified.
Edited 1 time(s). Last edit at 05/14/2008 07:11PM by Jeff S.
If any of you have the FAA references that document that 337's are no longer required for a GNS 430 installation, please post those or send them to me. I'm in the midst of a 337 paper chase right now and could use your help.
I believe the document that FlyGuyDon refers to is not actually a "regulation" but rather an FAA Advisory Circular.
AC 20-138A does indeed give guidance on installation of GPS equipment as a minor alteration as opposed to previous FAA guidance. This document is very informative giving examples of what installations should be considered major or minor installtions.
Appendix 5 of the same document specify criteria for GPS installations for VFR use only.
I'm not sure how to include links in my posts but you can google "AC 20-138A" or copy and paste the following URL in your browser.
PS! I am happy to see the link appeared automatically in my post above. It seems you just type or paste the actual URL into the post and voila the link appears.
BTW! AC 20-138A contains a lot of information. The portions relevent to determining whether an installation of GPS equipment is a major or minor alteration begins on page 10 and gives guidance on post installation checks required for IFR use. VFR only installations are discussed starting on page 12 with additional info in Appendix 5.
