NDB/RNAV approach

[tarp]

G.6, you said:

"My question is this: Since there is a transition route from a VOR w/ DME to the NDB, which is the IAF/FAF, can I legally use the RNAV to create a waypoint at the NDB and use it as lateral guidence on the approach? "

If the VOR is behind you and defines a transition route, why wouldn't you just fly "FROM" the station using the raw data VOR and the NDB in front. Why create a nebulous waypoint? Is it just so you can have it in front of you?

I agree with all that if an NDB approach is coming on your ride, the only unit that will eventually work on the approach will be the NDB, despite all your attempts to use RNAV's or GPS's or other sources. The thing I would be most afraid of (if you haven't practiced already) is the DME arc request. It is completely fair game for the examiner to ask you to just "fly an arc" as defined by some mileage off of a VOR.

One other thing with RNAV (VOR/DME) units. Watch the service volume (i.e distance from the VOR) when at low altitudes! Your friendly DE might be testing to see if you read that part of the AIM as well. Remember, below 1,000ft agl, the parabolic curve of a low service VOR falls from 40 miles to 10 miles of usable service (as compared to regular/high service model).

Our DE can play the best game of oneupmanship you've ever seen. Good luck on your ride.

 

[alvin]

I had my instr ride cancled 4 times by weather...I almost ran out of my 60 hour signoff before I took it...Then I had to learn a new plane, comm / nav panel etc...

I tried setting the GPS to act as a DME. As soon as it was set, the DE turned it off...


Don't sweat it...just go with whatever comes up

 

[avbug]

When I did my instrument rating practical test, there were no useable NDB's available. I created an approach using an AM radio station, and drew it up to match a Jepp chart. When the examine first saw it, he thought it was a legitimate approach, until he realized it was in pencil. He accepted it, I flew the approach successfully and to his satisfaction, and I got my instrument rating.

I had to buy six cases of crackerjacks before I found one with the ATP inside, however.

 

[A Squared]

When I did my instrument rating practical test, there were no useable NDB's available.

Was this because they hadn't been invented yet?

 

[avbug]

Didn't need them. We still were getting ample use out of two soup cans and some twine. And we were grateful!

(

And there were no operable NDB's or available NDB approaches within reasonable flying distance, or in the state)

 

[bigD]

And there were no operable NDB's or available NDB approaches within reasonable flying distance, or in the state

At some point that's going to be true again, and you will have seen it come full circle!

 

[ksu_aviator]

I didn't see anyone else address this so I will just to see if I can throw a monkey wrench into the whole thing. Is the NDB approach even approved for RNAV? I know most have been, but if it hasn't been then the simple answer is no. However its not bad situational awareness.

 

[groundpointsix]

No, it's not an approved RNAV approach; just a simple NDB. I was just asking about it for situational awareness purposes because in actual IMC you can bet I'm going to use it as a backup assuming I decide to even shoot the partial panel NDB in the first place as opposed to divirting somewhere with a positive guidance approach or even some sort of surveilance approach.

Tarp- to answer your question: The advantage of creating a waypoint over the NDB is that you could then fly the NDB final approach course by setting to OBS for the course and following the needles (for situational awareness only, obviously) I understand that flying the feeder route would only involve tracking outbound from the VOR, though at that point I'd probably be going direct to the NDB anyhow.

Thanks for the input everyone

 

[tarp]

Yeah, that's where I thought you were going - and of course the DE is just going to switch the RNAV unit off so you have to fly the ugly needle on the ADF or he's going to let you hang yourself on a service volume issue (busted).

Cruel guy - partial panel NDB for a checkride? I can see giving you a partial panel on a VOR, but thats just cruel to lose your DG on an NDB approach (FOR THE CHECKRIDE). He'll probably be the type that tells you not to look up at the mag compass (cheating a glance outside). I can hear it now, "keep your head down son and fly the approach, ask for the heading and I'll give you the value".

My instructor who was definitely out of the dark ages did that time after time - by the time I took the checkride, I felt like I could fly an NDB approach blindfolded and with one hand tied behind my back.

Good luck on your ride, you sound ready.

 

[bigD]

I swear, I must be the only person in the world that's weird enough to think that an NDB approach (full or parial panel) is less difficult than a VOR approach. No knob to turn - just look at the ADF needle and fly what's written on the plate. I was given a partial panel NDB approach followed by a miss and a hold, and I thought I had died and gone to heaven. For some reason I've found that finding a good wind correction angle while partial panel is easier and faster with the ADF than the VOR.

The only thing I don't like about NDB crap is listening to the stupid morse over and over and over again.