Certified or not GPS for IFR

[sglynn55]

I've read several chats on this forum about IFR requirements and it appears the general consensus is that a GPS needs to be TSO certified on an experimental airplane in order to fly legal IFR. 

How about we challenge that?  The more I read the more it appears that as the builder of the airplane you must "certify" that your equipment meets the functional requirements of TSOed equipment but that does NOT mean it has to be TSOed.  None of the EFIS instruments need to be TSOed.  Why would the GPS have to be?

Then if true that we (builders) only need to prove or certify our equipment can do the certified requirments, why not ask Dynon to help us show that instead of just saying we need a TSOed GPS in order to be legal IFR airplane?

EAA published an article that states what I'm saying but this chat room won't let me insert the link.  But you can check the EAA FAQs

I'm close to buying a panel and want IFR like my current Cherokee has with a Garmin 430.  But it seems like Dynon's EFIS and stuff can do it and meet the requirements even though it is not manufactured as TSOed.  But if we can show Dynon GPS can meet the functional requirements we can declare our airplanes IFR certified.

Right?

 

[airguy]

Legal IFR existed before GPS, remember....

A certified GPS is needed if you intend to use a GPS IFR approach, or to feed the navigational guidance to an autopilot. If you are using a non-certified GPS you cannot legally fly the IFR GPS approach but the other approaches are still available to you.

There is nothing at all that says you have to have a certified GPS in order to have an IFR aircraft. It just limits the types of approaches you are able to fly.

 

[GalinHdz]

Legal IFR existed before GPS, remember....

A certified GPS is needed if you intend to use a GPS IFR approach, or to feed the navigational guidance to an autopilot. If you are using a non-certified GPS you cannot legally fly the IFR GPS approach but the other approaches are still available to you.

There is nothing at all that says you have to have a certified GPS in order to have an IFR aircraft. It just limits the types of approaches you are able to fly.

Adding to this, the GPS must be certified for the navigation you are using, en-route only, approach only or both. Without a certified GPS you can not legally file /G on your flight plan, go GPS direct or fly a GPS (T) route while IFR.

 

[RVDan]

I do not think that you will find a non-TSO GPS that will provide guidance for GPS non precision or precision approaches. You would have to build the approaches yourself and that is one of the key issues.

 

[swatson999]

Or you could get access to the raw ARINC formatted datasets and figure out a way to read them in to your GPS, but you'd still not have things that are required such as integrity monitoring, etc.

Certified GPS navigators entail a lot more than just the GPS solution and the data...the algorithms, etc., are all designed to meet certain specs. I doubt an individual could accomplish the equivalent of TSO on their own...