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comments from gps users?

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Well-known member
Mar 30, 2002
You and your plane are good for IFR. Off you go IFR. You have a VFR GPS on board...can't afford the IFR pannel mount. You would love to go direct to that point 350nm away to save time/fuel. How many of you out there will ask for it? Do you say you are GPS equiped when you file your plan?
Comments anyone?
wouldn't need to tell FSS if you were GPS, I believe.

File direct for GPS usage.

As for using VFR GPS in IFR conditions, would you bet your life on it? It's between you and God. Good luck
I used to fly a King Air with a VFR GPS. I filed /A - but in the air if I wanted direct I would advise the controller I was either "Radar vector equipt" or TLAR equiped (That Looks About Right). They knew what I meant. Fortunately I've got IFR GPS now.

File /G, get cleared direct, oops VFR GPS doesn't have RAIM and won't tell you if RAIM not available, GPS signal gets very distorted, controller is busy and doesn't see you headed for a mountain, and POOF you're dead.

There's a King Air on the field that hasn't done the IFR cert of his unit yet. But he files /G all the time, gets cleared direct quite often, and is risking his company $50,000 per incident, his pilot certificates, his mechanic certificates and his $70,000+ job each time.

But what usually happens is the GPS gives inaccurate information because the database is expired and the pilot goes direct using the moving map to tell if the plane is in or out of airspace. The 40 nm wide line that is one pixel wide doesn't bust the pilot, ATC RADAR busts the pilot. Or they find themselves with an F-16 escort. . . Those are NOT Class "D" rings on GARMIN units.

Jedi Nein
And with the above said, HSI fails, A.I. tumbles, and the engine oil pressure just exceeded your heart rate. NRST Direct on a VFR GPS unit works mighty fine.
Just file /a, then when you're in the air say this...

N123AB: LA Center, I show El Paso at heading 090, 936 miles, could I have direct?

LA Center: 123AB, approved as requested.

As far as rocks or airspace goes, that's why you have the chart out...
I used to buzz around in an arrow that we had at our flight school with a hand held and file direct. I normally wasn't in hard IFR though. But on time another person rented it and was filing with flight service and they flied /A and the briefer made the comment that we filed /G last time. We just told him that it was inop. I also worked for a company that had a panel mounted GPS and was to cheap to get it certified so we filed /I cause we had Rnav but never used it. I never had a problem with the GPS not working either. I guess I was just lucky. The place I am at now has a KA100 and has a panel mount but it isn't certified either and that's what they use. I would think if you have the money to buy it and mount it you would have the money to certify it too. Just have a back up plan I guess.
What I've done in the past is filed /A then put in the remarks, VFR GPS equipped. I also filed from VOR to VOR in as straight of a line as possible. That way if I was in solid IFR I could cross check the VOR's and GPS against one another. Much safer in my opinion.
KSU Aviator, I wonder if the various ATC folks have the remarks section in front of them. I would think they just have the basics and not all the filed flight plan data.
I flew once with a captain on a B727 (lucky to have DME onboard)who asked the co-pilot to ask for direct San Diego after taking off from Chicago late in the evening. The F/O did as he was told and ATC approved it. A few minutes later, ATC asked if we were RNAV equipped. Not being RNAV equipped the F/O looked at the Captain for advice on how to reply. The Captain told him to tell ATC that we are CNAV equipped. All was well for a few minutes untill ATC called again and asked what CNAV was. The Captain picked up the mic and said, "It's Captain Navigation". We never got asked about it again. The Captain had his own portable Loran with him.
GPS IFR Certification

Ok, it's really easy to do an IFR cert on a GPS.
First, it must be a certifiable unit.
Second, it must be an IFR installation. (hooked to encoder, in full view of the pilot, no separate annunciator panel
required if internally displayed, etc. The shop just follows the STC.)
Third, it must be test flown. Our FSDO expects 3 approaches and overflight of 5 waypoints along with certain
other tests. Usually about 1.5-2 hours flight time. Other FSDOs require less. Those that require more, PM me
and we'll chat.
Fourth, a Form 337 removing the VFR only placard must be filled out and sent to the FAA from the avionics
shop (or "approved" person doing the cert).
Presto! IFR Certified GPS and the plane is now /G.

Total cost? $200-$500 depending on flight time and need for a datacard.

Not bad compared to a $50,000 fine, loss of pilot certificates, or the $12,000 cost of the unit (GARMIN 530).

Jedi Nein

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