Procedure turn inbound

[Amish RakeFight]

I just did a search on this topic and it still seems unresolved.

Anyone else care to contribute with more definitive FAA references?

 

[unreal]

I typically teach case break as "positive course guidance" necessary to start a descent. That's how I was always taught, and that's how I know most people do it. I guess that doesn't make it exactly "correct" as far as the FAA is concerned, but as A Squared said, you won't hit anything.

I think with the PTS now specifying a 3/4 scale deflection criteria on an instrument approach, that might be considered the "proper" time to start a descent. If you're close-in though, it may only take a couple seconds for the needle to uncase and get to 3/4 deflection anyway, so it doesn't really matter much.

The way that I personally do it is if I'm close-in or just passing a VOR that serves as the FAF, I descend when the CDI comes alive. That ensures that I'm going to actually make it down to MDA by the MAP. If I'm further out and have plenty of time, I don't like to rush. I like to stabilize the airplane on the segment, get any configuration changes done, then start the descent. All depends on where you are and how fast the approach is occuring.

 

[Amish RakeFight]

It's quite odd the FAA doesn't have an official defintion for being established. Therefore I'll go with the ICAO definition of "established" as it seems like good sense. I believe I o0nce read that the AF uses this definition as well. But the difference between 3/4 and 1/2 is slim. I've always began somewhere between 3/4 and 1/2 anyways.....


ICAO - "Established"

ILS/LOC/VOR - Half scale
NDB - +/- 5 degrees

 

[nosehair]

It's quite odd the FAA doesn't have an official defintion for being established.

Oh, Man ! It's not possible to have an "official" definition. The Pilot makes that decision - based on the knowledge that has been displayed here.

Different situations call for different definitions of "established".

Home Base - Flat land - Very Familiar Airplane/Environment: When the vor/loc needle comes alive or the adf needle is within 15 degrees, and my heading is within 30 to 45 degress, I am comfortable being "established" and can start down. I know I am within legal TERPs criteria, and My own head is comfotable with the known surroundings.

Very Strange Unknown Terrain/Environment/Equipment, I'm gonna getthe needle off the peg a little bit to insure it is actual navigation information, not an electical hiccup, so the PTS 3/4 scale or adf 10 degrees is my basic personal tolerance, which, by the way, is 'the way' it is taught - for the worst case scenario. When you are familiar and comfortable, and still know you are well within that broad fan of protected airspace, there is nothing "illegal" about comming down much sooner. far 91-wise.

 

[FL420]

I typically teach case break as "positive course guidance" necessary to start a descent. That's how I was always taught, and that's how I know most people do it.

How can you be sure that "case break" isn't actually caused by a temporary disruption of the signal(e.g.-caused by a large aircraft taxiing across the runway) or even a permanent loss of signal due to failure of ground-based or aircraft-based equipment that hasn't yet activated the failure flag circuitry logic? Do you always do a sensitivity check to ensure that a 5º OBS course change results in a ½ scale needle deflection and a 10º OBS course change results in a full-scale needle deflection?

I think you're asking for trouble descending at "case break" and no, I don't think most people do it that way. At least not professional pilots.

 

[unreal]

How can you be sure that "case break" isn't actually caused by a temporary disruption of the signal(e.g.-caused by a large aircraft taxiing across the runway) or even a permanent loss of signal due to failure of ground-based or aircraft-based equipment that hasn't yet activated the failure flag circuitry logic? Do you always do a sensitivity check to ensure that a 5º OBS course change results in a ½ scale needle deflection and a 10º OBS course change results in a full-scale needle deflection?

I think you're asking for trouble descending at "case break" and no, I don't think most people do it that way. At least not professional pilots.

Well obviously there is some thought that goes into it. C'mon, I'm not stupid. If you'd like to debate me on semantics, here you go: I descend when I have case break and I've seen that the CDI needle is actually alive and moving towards center.

On second thought, in my last post, I qualified the first paragraph with the second and third.

 

[FL420]

Well obviously there is some thought that goes into it. C'mon, I'm not stupid. If you'd like to debate me on semantics, here you go: I descend when I have case break and I've seen that the CDI needle is actually alive and moving towards center.

On second thought, in my last post, I qualified the first paragraph with the second and third.

But why is it moving toward center? What if it moves toward center, you start descending, and the needle goes back to full-scale deflection OR the needle centers up and THEN the FAIL flag comes ON?

I have seen both situations more than once.

 

[unreal]

But why is it moving toward center? What if it moves toward center, you start descending, and the needle goes back to full-scale deflection OR the needle centers up and THEN the FAIL flag comes ON?

I have seen both situations more than once.

Well, in your above post you mention the sensitivity check. I actually do teach that during the VOT check. 360 with a "from" indication, then go to 350, make sure the CDI swings 10 degrees. Then go to 010, make sure it swings 10 degrees. Do the same with the "to" indication.

I'll readily admit that I don't always do a sensitivity check, though. If one had been done recently with the VOT check, then I tend to skip it assuming we're going in VMC.

 

[FL420]

How long are you gonna keep dancing around the questions?

 

[unreal]

How long are you gonna keep dancing around the questions?

Alright, we're done. Why you decided to single me out is beyond me, considering my answers were really no different than just about everyone else in the thread. Have a good one.