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2019 GRT Horizon HXr IFR WAAS approaches TSO pursuit update?

Since it is reported that process cost more than a million to complete, is it really likely that they will invest that heavily into such a relatively small market?
 
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Since it is reported that process cost more than a million to complete, is it really likely that they will invest that heavily into such a relatively small market?

The title of the post is mis-leading, IMHO. I do not believe GRT has any intention of pursuing a TSO. Their web site quite clearly says so, "...for use in VFR or emergency conditions only...".

However, it's easy to read between the lines. I for one have been flat out surprised by the reversal of the FAA, in recently allowing non-TSO'd Dynon, GRT, and Garmin EFIS units (approval is only for the AI) in normally certified aircraft. I presume GRT is hoping for the same with GPS navigation under IFR rules. I note that in recent times the FARs themselves have gone from "TSOd" to "suitable" in describing what the FAA will approve for IFR GPS.
 
No misleading. I'll get a Garmin 175 IF GRT is not going for IFR actual WAAS approaches.

Dead serious question.

Glad I skipped a used or 400W, which was my current plan til GRT started with the HXr end of last year.

Last email sounded hopeful, so I wanted to get any Sun n Fun updates without bugging Jeff.
 
Oooo... please elaborate. :)

When ifr gps first appeared, the FARs specifically used the word "TSO" as to what equipment was required. Now, they use the word "suitable". And if you go to FAR 1.1 (definitions), it says (paraphrase) "...suitable gps is what the FAA says it is (!).....a TSO is one way, but not the only way, to produce a suitable gps...."
So they've left the door open, a crack.
 
I just talked to GRT today at Sun n Fun, but did not ask the TSO question.

Flying a non-precision or ILS using an FMC (121 version of a navigator) has been taught for more than a decade in the US, and is legal as long as the raw data is referenced for the approach. I never actually did this in the US. The last 10 years I haven't flown an airplane east of Honolulu. I have probably done over a thousand of them. Many were built into the FMC (navigator). Maybe 100-200 times I built the approach with LAT LONG, and monitored the NDB or VOR.

To truly fly an approach using GPS as the primary, one of the requirements is to be notified if the "quality" of the GPS/AHRS is no longer suitable for the required accuracy of the approach.

GRT is doing this. The EFIS provides this notification. I see no issue using a GRT, or any EFIS, to fly an approach as long as the raw data is referenced for accuracy. I wouldn't be surprised if the FAA doesn't allow a WAAS GPS aircraft to fly a full on GPS approach, as long as their is notification of the accuracy of the GPS/AHRS. I am not sure when it will happen, but I think it will.
 
If it were that easy, Dynon would have already done it. Their owner has the capital to pull it off. Makes one question why they have not. Maybe the investment is not worth the reward or the risk that will come with it with such a relatively small market.
 
EAA's position is that the system you install does not necessarily need to be TSO'd, but if it's not, you better be prepared to show the FAA that it meets TSO specs if you wish to use it for IFR ops. And that would be on you, the builder, to provide evidence of testing and analysis that shows this equipment you installed complies with the TSO.
 
EAA's position is that the system you install does not necessarily need to be TSO'd, but if it's not, you better be prepared to show the FAA that it meets TSO specs if you wish to use it for IFR ops. And that would be on you, the builder, to provide evidence of testing and analysis that shows this equipment you installed complies with the TSO.

Yes and those TSO specs are akin to the US Tax code in their requirements......
 
Yes and those TSO specs are akin to the US Tax code in their requirements......

and therefore really requires the manufacturer to state that they meet the performance of the TSO. As soon as GRT makes this statement, they really open themselves up to serious liability if they cannot prove it or otherwise show a meaningful effort in doing so. Otherwise it's negligence and they are wide open. If GRT doesn't make that statement, the FAA would never accept it in my opinion and the builder and/or pilot takes on that liability.

While it's very exciting to potentially see this happen some day, I just can't see GRT exposing themselves to that level of liability. This is not like adsb, where most of the TSO testing is on the GPS antenna and reception circuitry and the manufacturers can rely upon the testing and compliance statements of the few component providers that have actually done this testing and understand the TSO in order to sell components to certified providers.

While speculation, I also believe that the FAA relaxed their standards (in allowing stated conformance instead of compliance testing for TSO) in the ADSb market in order to help get products to market and ensure there was not resistance to adoption and therefore meet their timeline. It's unclear if this was a one time thing or a trend. I certainly hope it's the later. The Navworx distaster showed that they don't simply want a statement; They want some meat behind it and they are watching.

Larry
 
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Yes and those TSO specs are akin to the US Tax code in their requirements......

-:) A great analogy!
The only hope for small manufacturers is if the FAA allows demonstrated conformance to the Performance specs of the TSO, which is much less work than the full TSO. For example, the full TSO contains requirements on ?parts traceability?. This alone could overwhelm a small company.
 
I believe Dynon and Garmin both are going where the meat is in the market. Nothing against them.

I would not guess when the FAA will allow GPS based approaches off an EFIS, but I do think we are headed in that direction. GRT and maybe MGL both are equipping their EFIS's with some built in functionality for this. I thought I was going to buy Dynon/AFS, but I am pretty sure I am going with GRT for this reason. If more customers wanted it, I am sure the other two would follow suit.

Flying a VOR/LOC/NDB by using and EFIS based approach should be totally legal, as I have been trained by 4 airlines to use it, and flew them at 3. I never had to do one in CONUS.
 
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