comments from gps users?

[buzzer]

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?

 

[troy]

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

 

[Capthuff]

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.
Cappy

 

[JediNein]

Howdy!

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.

Fly SAFE!
Jedi Nein

 

[JediNein]

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.

 

[Wiggums]

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...

 

[Dep676]

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.

 

[ksu_aviator]

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.

 

[buzzer]

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.

 

[JediNein]

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).

Fly SAFE!
Jedi Nein

 

[buzzer]

JediNein,
Hmm...Perhaps an inexpensive, no map, used IFR GPS installed/tested would allow you to use your fantastic VFR GPS as your "main" companion during IFR flights on a budget.

 

[sstearns2]

Hello,

You can get a factory reman King KLN-89B for about $1700. There may be an IFR GPS that will just plug into your current tray.

As far as using a VFR GPS in actual IFR.... I have a lot more faith in the GPS signal than any VOR signal. I've seen VOR needles wander all over the place, but I've never seen a GPS needle so much as quiver. The question is whether it's worth risking your tickets or not.

Also, someone previously talked about RAIM. I don't belive RAIM monitors the signal at all, it just looks into the future and makes sure you will have acceptable satalite geometry along your route. I beleive that there are enough GPS satalites over the US now that it is never a problem. I've never seen less than 7 or 8 satalites available on my handheld. The minimum is 4 to get a solution and they can't be in a straight row across the sky. (The geometric accuracy of the signal is directly related to the area enclosed by connecting the satalites together, the larger the area the better the solution.) Has anyone see less than 4 anywhere?? Also most GPS units actually monitor more that the minimum number of satalites and constantly cross check between them, so the unit will quickly figure out if it's getting a bad signal. Also the military monitors all the satalites all the time.

Scott

 

[JediNein]

Howdy!

Yes, I've seen an IFR GPS disagree with a VFR LORAN, a handheld GPS, and the view out the window. The IFR GPS was the most correct, and the view out the window was the absolute correct.

I've watched another IFR capable GPS, VFR installation, quit with database and other errors while the VOR continued working.

I can tell when a student is using GPS navigation versus the VOR because the VOR scallops on a certain approach. Lotsa fun.

I've watched a student fly a GPS approach in actual to see the "RAIM not available" message just before the FAF. It gave the student a much needed wake-up call. If he would have checked the GPS NOTAMS, he would have flown the VOR approach instead.

I watched another GPS unit, IFR installation, just not certified, give an "estimated position" when it lost signal reception from all but two satellites. The NDB was the only signal available in that particular situation. There was a lot of rock between us and the other satellites.

I've also seen all sorts of wierd and unusual error messages from the units when installed incorrectly. Usually it is a missing ground wire connection, or two flip-flopped. The worst occur when the shop forgets to reset the sensitivity, squelch, and OBS setting.

As for the eBay sale on both the KLN89B and Garmin 430, I know the manufacturers tend to yank dealership authorizations for selling new units there, used, well, good luck. Buyer beware. It will be interesting to see how much those go for. The completed sales on the GARMIN 430s show about $5200 through $5900. Not much more money and one gets a new unit; $960 through 1800 on the KLN series. Still much cheaper than a couple of pilot certificates.

Fly SAFE!
Jedi Nein

 

[Timebuilder]

I submit that there is a difference in many units between a "VFR only" unit, and a unit which is certified for IFR use, but has an expired database. I would only use the VFR unit as an adjunct to the VOR nav system. I would put significantly more faith in an IFR unit which is not currently "legal" due to the data, particularly for enroute use above obstructions, such as above 14,500 MSL. I would not shoot an approach GPS only with expired data, but I would have it up and running to augment the VOR indication.

Using the moving map function, I have never been mislead by a GPS because of the course line being too wide in terms of pixels or miles. I just change scales to have the map represent a smaller area.

 

[aggiepilot87]

GPS is more reliable than VOR and LORAN at any given point in the US. A particular GPS reciever may be more or less reliable than a particular VOR or LORAN receiver, though.

Expense and one's ability to absorb it is *relative*. I'm glad Jedi can buy Garmin 430's off eBay and have them installed and kept current in her(?) plane. I can't.

But I can buy *enroute charts that are current* and use my $89 Garmin eTrek GPS to give me a direct heading. Where in this assumption did I say I wouldn't be checking for obsticles, keeping track of "primary" navaids, assuring alternate airport availability, or keeping good situational awareness?

For those folks not flying >$1 mil aircraft, I think filing /a or whatever is appropriate (minus the handheld), *then* asking for direct by own nav or "suggesting" a direct vector, is totally acceptable and legal. Therefore the risk of loosing a certificate is not a factor.

If they ask how you determined your direct nav, CNAV sounds good to me... maybe a very sharp pencil and a good straight edge!? same difference really.