GPS Approaches IFR

Center_Mid

Well-Known Member
In order to fly a GPS approach, are you required to load the approach into the GPS, or can you simply fly from fix to fix (using the moving map) and descend as called for by the IAP?

I ask because I was on a GPS approach the other day and the KLN 94 wouldn't "pink line" the damn procedure route - which seems to indicate that the approach isn't loaded (even though I JUST loaded the damn thing). I suspect that a prior flight plan loaded by the renter before me was fouling up the works. My instructor suggested that I just fly the procedure by pointing the airplane at the fixes and descending when necessary.

Ok fine, but would that cut it on a checkride??
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From the GPS approaches I've shot I had to load the approach. Then the approach would either start at the initial approach fix or when I manually started it. At FlightSafety, we were not allowed to use the GPS for our approaches. The examiner either turned it off or told us not to mess with it, either way you can't beat the old fashioned way of doing it with the dials.
 
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From the GPS approaches I've shot I had to load the approach. Then the approach would either start at the initial approach fix or when I manually started it. At FlightSafety, we were not allowed to use the GPS for our approaches. The examiner either turned it off or told us not to mess with it, either way you can't beat the old fashioned way of doing it with the dials.

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Really? Can a pilot get an instrument rating in an aircraft with a GPS and simply ask the DE not to test for GPS approaches? I would think that eventually you'd need to be tested on it.
 
I think he meant we weren't allowed to use the GPS to monitor an ILS, or better yet...an NDB approach. And that was just on checkrides, at least in my experience.
 
I'm no expert, so this advice may be worth about what you paid for it, but:

I would bet my shirt that you'd get busted for flying a non-loaded and non-armed GPS approach on the checkride. And I sure as heck wouldn't do it in IMC if my life were depending on it. After you load a GPS approach, as you approach the IAF and continue on toward the FAF and MAP, the scale of the CDI decreases, thus increasing it's accuracy. I don't remember the exact numbers (you can find them in the AIM) but it's something along the lines of 3-5 miles from centered to full deflection before you start the approach and it drops down to around .3 miles for that same deflection inside the FAF. Plus, the requirements for RAIM get more stringent with an armed approach, I think.

Bottom line, DON'T try it on the checkride or in IMC. During practice with a safety pilot in VMC anything goes, so hopefully that is what your CFI was talking about.
 
Hi Needle,
I hope that you instructor was just saying that was okay for practice, and hope that he emphasized that it is definitely NOT okay for a checkride or for sure in actual IMC. Your GPS approach needs to be loaded and HAS to go from terminal to approach mode before reaching the FAF or you have to go missed.
 
You definitely need to load and fly the approach. You may not have activated the approach. Choose the approach you want to fly and when it asks to activate it then press enter. You then will have to choose the IAW (sometimes there are several). Highlight the one you want and hit "direct". That should have you on the approach. Also, you are correct, the GPS has to go to .3 sensitivity (this happens within 2 miles of the FAW), and say "ACTV" in order for you to continue. I would shoot as many GPS approaches as I could since some airports don't have any other kind, and they can be a little tricky doing procedure turns and holds (OBS) if you aren't used to them.
 
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From the GPS approaches I've shot I had to load the approach. Then the approach would either start at the initial approach fix or when I manually started it. At FlightSafety, we were not allowed to use the GPS for our approaches. The examiner either turned it off or told us not to mess with it, either way you can't beat the old fashioned way of doing it with the dials.

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Which is one way in which flight tests do not come close to reality in terms of what you would actually do. A much better way to conduct a checkride would be to allow the candidate to use "all available means" of navigation and information, provided a) it was legal to use it for that purpose and b) the candidate used it correctly. That would determine that candidates overall judgment and decision-making ability along with the opporuntity to assess his level of knowledge about what's available to him in the aircraft. I do not view use of the GPS system, when used carefully and correctly (as with anything in flying), to be "cheating", "easy" or otherwise inappropriate for checkride usage.

For my 135 rides, my POI wants me to use everything that I can on that aircraft to help me do my job. That means GPS, A/P, FD, TCAS, WX Radar, kneeboard and coffee pot, among others. If he wants to test my ability to live without a certain something working, then it unexpectedly "fails" for a few minutes and he watches how I deal with the situation. After he is confident that I can handle life without that piece of equipment, it miraculously fixes itself and on we go with the checkride.

If use of GPS and other advanced technology is not regularly tested on checkrides, then like anything else in flying, it probably won't get taught. What ends up happening then is your newly certified Instrument Pilot goes out and flies and airplane with a fancy new GPS in it, has no idea how to use it, and ends up as some crash statistic either because he was too fascinated by this box of tricks and forgot about his other duties, or didn't use it, when use of it could have saved his life. Exaggerated situation, yes, but the point is that we're moving more and more towards advanced technology and unless it is taught, tested and used correctly, it's going to end up hurting many more people than it helps.

Ok, I'm done ranting
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Ray

Ray
 
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From the GPS approaches I've shot I had to load the approach. Then the approach would either start at the initial approach fix or when I manually started it. At FlightSafety, we were not allowed to use the GPS for our approaches. The examiner either turned it off or told us not to mess with it, either way you can't beat the old fashioned way of doing it with the dials.

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I just finished at FlightSafety in August, and we did use the GPS for airports that had published GPS approaches. I even had to do one on my instrument checkride. (I do agree though that we were not allowed to monitor an NDB approach with the GPS.)

Grayson
 
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Hi Needle,
I hope that you instructor was just saying that was okay for practice, and hope that he emphasized that it is definitely NOT okay for a checkride or for sure in actual IMC. Your GPS approach needs to be loaded and HAS to go from terminal to approach mode before reaching the FAF or you have to go missed.

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Well, he didn't really say for sure. I'll ask him the next time I see him. Luckily, I took the checkride today and the KLN94 loaded the approach and made the switch into appr mode without any problem. For future reference, I'll go missed in that situation. Still, does anyone know of a relevent FAR or AIM section dealing with this?
 
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Still, does anyone know of a relevent FAR or AIM section dealing with this?

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AIM 1-1-21(o)(8) [2003 version] sheds some light on the subject. Primarily, it appears that the proper sensitivity for course deviation and RAIM are not guaranteed if the approach procedure isn't loaded and active.
 
Not too familiar with the King GPS but on the Garmins you can load the approach but then you also have to activate it as well in order to get it to become effective.....
 
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