"Established"

[memooch]

I've been told that ICAO defines "established" as at least 1/2 scale CDI. The AIM is far more very vague, so the ICAO definition is obviously better to teach instrument students. Of course, the latest PTS permits in most cases no more than 3/4 scale for most tasks.

HOWEVER, I'm not able to find a decent reference for this. If anyone knows where this is actually published, please let me know! If this discussion is in a thread already, please enlighten me...

Thanks all!

 

[PURPLEHAZE21]

I might be wrong here, but, I think you might be mixing two things together. To determine if you are "established" on an approach you must have "needle/ course deflection" on the CDI (LOC/VOR). The Instrument Handbook does not give an actual amount of degrees due to winds and being vectored which will or can alter the rate of intercept. Again, it's been 20 years....but...we usually call "course alive" to indicate needle deflection, then turn as required for intercept. Is'nt the PTS giving you parameters for flying the approach (course guidance) ? I'll get back too you...

 

[trickle99]

The Instrument Procedures Handbook - Appendix B covers this. Specifically page B-5 where it references the ICAO procedures for air navigation. In a nutshell you are considered established when within half full scale deflection for ILS and VOR and within plus or minus 5 degrees of the bearing for NDB. Yes the AIM is quite vague.

 

[midlifeflyer]

ICAO uses a +/- X degrees standard. The US uses the English language.

I don't think the AIM is vague at all and that, like all attempts to overdefine something, the ICAO definition comes up short (unless one thinks that when the inbound course is 355, passing through 350 on a heading of 080 with a tailwind is "established.")

 

[nosehair]

ICAO uses a +/- X degrees standard. The US uses the English language.

I don't think the AIM is vague at all and that, like all attempts to overdefine something, the ICAO definition comes up short (unless one thinks that when the inbound course is 355, passing through 350 on a heading of 080 with a tailwind is "established.")

KA-A-RAACK!! (sound of a bullwhip kracking)

 

[JAFI]

Mark, Great point..... I liked it so much I read it three times....

But ya know, You are "confusing" someones opinion with logic and facts. How dare you.....

 

[MauleSkinner]

... (unless one thinks that when the inbound course is 355, passing through 350 on a heading of 080 with a tailwind is "established.")

Ah, but one must assume that when one reports "established", they're actually established within the established parameters of The Establishment.

...And we all know what happens when you "assume"...

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You look like a friggin' idiot!:smash:

 

[trickle99]

Guys,

Was just trying to answer the posters question which was where is this referenced. The half scale and plus or minus five degrees bearing comment surely wasn't my "opinion" on the matter. The ultimate goal is to stay within protected airspace and the FAA Instrument Procedures Handbook, Appendix B (B-5 through B-9) spells out the cockpit indications and tolerances required for each phase of flight.

 

[lawfly]

I think the original poster/asker meant "at most /2 scale", rather than "at least 1/2 scale" ?

 

[PURPLEHAZE21]

I referenced the PTS and I believe the +/- 5 is in reference to actaully shooting the approach and being within parameters. This is a good question for the ATC section of this forum...Good luck and dont hit a mountain....