legal to install a non tso EFIS ?

DKirkpatrick

Pre-takeoff checklist
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DKirkpatrick
hello. buying an older airplane and need to install an AV-30 or Garmin G5 for non vacuum AI. The airplane has an AI but runs off input from an old external Venturi, etc., etc... The newer AV-30 would give me AI plus alot of other EFIS information, but they seem to be alot cheaper if you buy one that's "non TSO"...
Question is, can I buy and get installation on one of those if I move the old AI to the right side of the panel, but leave it installed and the old vacuum system in place?
THANKS for the help w this
 
can I buy and get installation on one of those
Yes it can be legal to install one of those however it falls more on the type of installation than whether the item is TSO or not. For example, if your installation is considered a major alteration then usually any money saved is lost on getting the approved data to make it happen. Most TSO or "certified" versions come with some sort of approved data like a STC. That said, regardless what route you wish to pursue it will always be subjective to the mechanic or shop who will be performing the work so perhaps start the discussion with them to see where they stand on the issue.
 
Even if you can get a mechanic to install it and even sign off as a minor alteration, the next mechanic that looks at it may have a problem with it. Most mechanics don't check those things when they do inspections, especially if they didn't know how the plane used to be. If you were to have an accident, then it's possible that they would look at that if they determined that the cause of the accident was related to that. There are a lot of things you "can" do and probably never get caught on, but there are things that you "may" (allowed to) do that you are fine even if you get inspected. Example, you can drive 90mph in a 70, but you will probably get nabbed if you pass a cop. If you drive 70 in a 70, you can wave at the cop and not worry that you will get pulled over. You have to decide if it's worth the risk. The valavionics argument provides a valid point to consider. The issue is the approved data with a major alteration, if it is considered a major alteration. The Val issue is that changing out a com radio with a com radio is not a major alteration, so a minor alteration is handled one way. Changing out a nav/com with a gps/nav/com is a major alteration because you have changed the capability of the panel substantially, unless you placard the GPS as "for var use only" or some other thing (and even that could be debated).

In summary, since they have an FAA/PMA and STC version, your safest option is to have that installed per the STC.

This advice is worth what you paid for it.
 
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In summary, since they have a TSO and STC version, your safest option is to have that installed per the STC.

Just to clarify, there is no TSO version of the G5 (or G3X, or Dynon's HDX). They have an STC without a TSO.
 
Just to clarify, there is no TSO version of the G5 (or G3X, or Dynon's HDX). They have an STC without a TSO.
I believe the uAvionix is also STC-PMA with AML.
 
For the $400 difference in price, I would go with certified AV-30 and remove the vacuum AI and Venturi...but that was not what you asked.

The link I posted above does not pertain to just a nav com install.
 
FYI: if any of the above EFIS were PMA'd they wouldn't need the STC per se as a PMA covers design, install, and production approvals. Its my understanding the "certified" versions of all these type instruments are mfg'd under a production certificate with the design and install approvals covered by the AML-STC and are not marked as PMA.
 
Some PMA’s are only production approvals, not installation approvals. Some are for direct replacement (no STC required), some are in place to support parts production for STC’s.
 
Some PMA’s are only production approvals, not installation approvals.
FWIW: All PMA applications/approvals require the listing of the specific aircraft model the part will be installed in, ie, installation approval. No exceptions. And the only difference between a standalone PMA and a PMA under an STC is the design side which is approved through the STC process that in turn lists the installation approval. There are several guidance docs that get into more detail.
 
wow. thanks for all the great information.
 
A supplemental type certificate (“STC”) is a design approval only. It does not provide any inherent production approval. An STC is usually developed when there is no product that meets a required need. An STC holder who wants to produce articles for use on aircraft will need some other production arrangements (in addition to the STC). For example STC holders may use production approval holder or parts manufacturer approval (PMA) to obtain FAA production approval for parts where the design has been approved under an STC.
 
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