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What to put in the panel GRT LPV GPS

Deweyclawson

Well Known Member
For those still considering what to put in the panel, or are considering an upgrade.
I talked to Greg Toman, Head Guru at Grand Rapids Tech, this week at Sun n Fun. The long awaited LPV approach certified GPS is about to go into the beta test stage.
The really good news - NO longer $3400 but is now $750
More good news, NO subscription fees. Simply download the nav data base from GRT to your memory stick, every 4 weeks, and plug the memory stick into the efis.
More good news. No additional GPS is required. The uAvionix ADSB coupled with the GRT 2020 GPS provides the WAAS GPS signal and the RAIM integrity checks. The uAvionix SkyFyx GPS also works but does not have the integrity checks. Some other GPS' may also work but without the integrity checks.
$10-$15,000 for a Garmin or $750 for GRT.
What's not to like?
 
What standard is it being certified to meet? Or is there a new TSO for this category?

If this does nothing more than provide a competitive pricing option to Garmin subscriptions, I would consider it a win for the experimental community.
 
Built to standards

The "LPV GPS" is actually just software. It is designed to appropriate TSO standards, according to the GRT web site, but it is not "certified" so is "experimental use only."
In addition to being a replacement for Garmin subscriptions, it is a replacement for expensive Garmin hardware. Cost savings lessened somewhat by still having to buy a com/nav.
Also you can keep your existing transponder with the uAvionix/2020 ADSB/GPS
 
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Legal statements from GRT

From GRT's webpage:

"These approaches are legal to use in VFR conditions for instrument instruction and currency. FAR 91.3 allows their use in an emergency."

"We make no claim regarding the legality of our GPS approach when intentionally flying in IFR conditions."
 
The "LPV GPS" is actually just software. It is designed to appropriate TSO standards, according to the GRT web site, but it is not "certified" so is "experimental use only."
In addition to being a replacement for Garmin subscriptions, it is a replacement for expensive Garmin hardware. Cost savings lessened somewhat by still having to buy a com/nav.
Also you can keep your existing transponder with the uAvionix/2020 ADSB/GPS

I'm not sure I agree.......

If the intent is to fly IFR, you still need a TSO certified GPS Navigator per the FAR.

Training for IFR in VFR conditions is ok in the early stages of training, but I would highly encourage to train is as much IMC as you can find for the experience. It's not the same experience as doing the approach in VFR under the hood.

I'm not sure I see the value in a VFR only LPV approach.
 
If the intent is to fly IFR, you still need a TSO certified GPS Navigator per the FAR.

Well... about that...

The GPS has to meet the performance requirements of the TSO. It does not technically have to have the TSO approval itself. This, in fact, is why we are able to use "non-certified" ADS-B solutions in our homebuilts--the manufacturers of these systems demonstrate that they meet those requirements, but they don't go through the approval process to produce them under the TSO umbrella. (side note: certified airplanes can also use non-TSO'ed ADS-B solutions... but getting approval to install them is the trick. TSO'ed units can be installed by 337 on most light aircraft; a non-certified unit would have to be done via the much more expensive STC process... which Dynon has now done with Skyview).

One could, if desired, produce an LPV-capable IFR GPS system, prove that it meets the TSO performance requirements for the GPS itself and the database, and use it. The trick is that documenting that performance is a tall order (read: expensive), and the odds of recouping that cost through sales to essentially only a small fraction of the homebuilt market, has made it so far a non-starter. Anyone wanting to make an IFR GPS has gone the full TSO route so as to be able to capture sales to the certified market.

This, I think, is also why it's harder to find a "basic" IFR GPS now (e.g. a refreshed GPS-400W). Anyone installing one on a certified ship is going to want as much bang for their buck as they can get, and get things like weather and traffic and terrain and nav/com and all that other stuff, since they have limited real estate on the panel. We on the homebuilt side often have all that already in our EFIS, so we don't really need it on the IFR GPS, but we're such a small part of that market that it's not worth developing something like that just for us.
 
I think Bob M (too many Bob's -:)) has summarized the situation well. I found some FAA guidance material that said, "... a TSO is one way, but not the only way, to .... meet the standards of an approved system." But those standards are complex, and I honestly doubt that most inspectors at the FSDO understand them at all. I for one am curious to see what happens next. My guess is the FSDO's will strongly oppose non-TSO'd IFR-GPS units, if they're asked. My guess is some pilots just won't ask. (I also guess that some pilots are even now shooting approaches with little more than an iPad). A few years ago I would have bet that the FAA would never allow a non-TSO'd Dynon as the primary or sole AI in a 172, but I would have been wrong. I hope I'm wrong on this, too, and the FSDO's will not oppose this. It's well past due for IFR GPS prices to come down to reasonable numbers, at least for part 91 operations (IMHO).
 
I think Bob M (too many Bob's -:)) has summarized the situation well. I found some FAA guidance material that said, "... a TSO is one way, but not the only way, to .... meet the standards of an approved system." But those standards are complex, and I honestly doubt that most inspectors at the FSDO understand them at all. I for one am curious to see what happens next. My guess is the FSDO's will strongly oppose non-TSO'd IFR-GPS units, if they're asked. My guess is some pilots just won't ask. (I also guess that some pilots are even now shooting approaches with little more than an iPad). A few years ago I would have bet that the FAA would never allow a non-TSO'd Dynon as the primary or sole AI in a 172, but I would have been wrong. I hope I'm wrong on this, too, and the FSDO's will not oppose this. It's well past due for IFR GPS prices to come down to reasonable numbers, at least for part 91 operations (IMHO).


We're getting a bit off topic and I really don't want to steal GRT's thunder, but....

I don't think it's FSDO that I'm worried about. I'm more concerned about insurance underwriters and their opinion. I think that they would claim that the FAR requires a TSO or demonstrated data that proves it meets the TSO or they will most likely deny any claims for incidents that occur in IMC.

I think this is a step in the right direction, but until GRT states it meets the TSO and authorize use in IMC conditions, I think it's just tempting people to push their luck.
 
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