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When can you descend

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ACAFool

Well-known member
Joined
Mar 25, 2003
Posts
100
If you are cleared for a vor approach (full procedure) when can you descend to the outbound leg altitude. Is it once you cross the vor or do you have to be established on the outbound radial prior to descending.

Thanks
 
ACAFool said:
If you are cleared for a vor approach (full procedure) when can you descend to the outbound leg altitude. Is it once you cross the vor or do you have to be established on the outbound radial prior to descending.

Thanks
"November 12345, maintain 3,500 UNTIL ESTABLISHED, cleared vor 12 approach."

Once you're established on a published portion of the approach per the approach plate, you are able to descend to the altitude applicable for that portion of the approach.

I think that there was an airline accident that mandated the use of the phrase "maintain x altitude until established." I don't remember which one off the top of my head, and quite frankly don't care to look it up that much.
 
I've heard debate about this since the begining of my instrument training. I assume you're talking about whether or not the needle on the HSI or OBS is moving? Like you just crossed the station and the needle hasn't settled down yet or is still pegged on the side? I've never heard on official explanation, and had people argue both ways. I figure, if you just crossed over the station, heading in the right general direction (give or take any wind which you may or may not have figured out yet), and know exactly where you are, go ahead and start on down. Just make sure you center that needle in short order if you do. Otherwise you can spend all day fidgeting with the needle and run out of 10 miles to make your PT.
 
Within 10 miles of the fix has nothing to do with starting a descent. Some approaches have arc that are in excess of 20 miles of the station. Pilotkman has it right, you must be on the pulblished segment of the approach. (the short version).
The 10 miles is max distance from the FAF and that had to do with terrain clearance for a course reversal procedure.
Any of you new CFI-Is or Terps experts care to elaborate.
 
This is actually an interesting subject for which there is no clear answer that I've been able to find. I did a bit of research on this over the years and only got a bit more confused.


We've all heard this phrase used in clearances "...maintainXXX until established...". I asked an FAA inspector friend to find me "THE Official FAA Definition". He and his officemates spent two days and could not locate any FAA document defining it. Amazing, huh ?

Well, my company had a definition they claimed came from the FAA Inspectors Handbook. Why such info would be located there??? You tell me. My FAA inspector friend could find no such reference.

But, my company said it was "...5-5-alive..." Within 5 degrees of course centerline on VOR & NDB and LOC alive for LOC/ILS approaches.

Well, that got changed further over time based on what my company said was ICAO-based criteria ( can't say one way or the other...maybe YOU can...). Let me Quote from my company Ops Specs:

"The aircraft shall cross the fix or facility and fly outbound on the specified track as necessary to the specified altitude. If a further descent is specified after the inbound turn, the descent shall not be started until established on the inbound track("established" is considered being within half scale deflection for the ILS and VOR, or within +/-5 degrees of the required bearing for the NDB)."

Well, on HSI's "half scale" is one dot. So, it's one dot...one dot...five.

When you get started talking about this TERPS-OPS SPECS-FAR-ATC procedures, you open a can of worms. I guess my point is "show me the Official FAA Document". If it's buried in some obscure place only F. Lee Bailey knows about, why is it there rather than in a book/document/FAR where pilots have ready access to it ?

This was a great question and shows how confusing some everyday issues can be.

I've given the garden-variety line pilot point of view. Now....all you F. Lee Bailey's...what say ye ??????
 
bafanguy said:
We've all heard this phrase used in clearances "...maintainXXX until established...". I asked an FAA inspector friend to find me "THE Official FAA Definition". He and his officemates spent two days and could not locate any FAA document defining it. Amazing, huh ?
I don't know what you mean by "THE Office FAA Definition," but here is an FAA publication stating the requirement:

7110.65
4-8-1
b - For aircarft operating on unpublished routes, issue the approach clearance only after the aircraft is:
2 - Assigned an altitude to maintain until the aircraft is established on a segment of a published route or instrument approach procedure.
Note
1. The altitude assigned must assure IFR obstruction clearance from the piont at which the approach clearance is issued until established on a segment of a published route or instrument approach procedure.

If you're wondering what officially qualifies as "established," check the AIM. It has information about anticipating turns to a new radial over a VOR/fix, etc.

Between those two sources, looks pretty cut and dried to me.
 
2105,


Your reply illustrates the problem. You quoted 7110...the air traffic controller's handbook !!! Do YOU have a subscription...do most pilots read this ?? And, what's more, the quote did NOT answer the question.

Your AIM reference refers to en route course changes, not instrument approaches.

By "Offical FAA Definition", I mean..SHOW ME WHERE IN YOUR OFFICIAL GOVERNMENT DOCUMENTS YOU HAVE DEFINED " ESTABLISHED ON AN APPROACH PROCEDURE COURSE "
Based on your references, it is anything BUT "...cut and dried...". In fact, you have demonstrated how confusing this issue is.

Show me the definition...
 
Lets see here

From what I remember established on an instrument approach means VOR less than 3/4 scale-NDB within 10 degress of course. The instrument PTS states 2 different standards one for not on the Final Approach segment (less than a full scale deflection) and for on the final approach segment( no more than a 3/4 scale deflection). However in the case of an RMI regardless of which segment you are on you are to be within 10 degress of course. However the ATP PTS requires max of 1/4 scale for ILS. I guess since I brought up the ATP standards being different that Instrument rated pilots maybe my guess of what it means to be established is shot out the window. I would imagine the answer would bw found in the TERPS manual. The more I type the less I feel I know the answer so I'll quit.
Peace
 
Willis,


I feel your pain, Bro !! I don't know what "instrument PTS" or "ATP PTS" is. If you are referring to an FAA Flight Test Standards Guide delineating acceptable deviations for an FAA rating/check ride, then we're not talking apples and apples.

SHOW ME THE FRIGGIN' FAA DOCUMENT THAT DEFINES "...ESTABLISHED ON..." for purposes of you and I, as regular guys flying an approach to earn a living without huring anyone. SHOW ME...

And don't quote 7110.65(e)...pilots don't read the Air Traffic Controllers Handbook, nor are they required to.

I'm on your side...great question, huh ??
 
bafanguy said:
2105,


Your reply illustrates the problem. You quoted 7110...the air traffic controller's handbook !!! Do YOU have a subscription...do most pilots read this ?? And, what's more, the quote did NOT answer the question.
1- It's the 7110.65. There are at least two publications in the 7110 series.
2- Yes, I do have a copy one. Anyone can look through it at http://www.faa.gov/atpubs/
3- Simply because it is the 7110.65 doesn't mean that pilots are forbidden from reading it or taking the references it gives into consideration. Take a look at it sometime and learn.

Your AIM reference refers to en route course changes, not instrument approaches.
No, it references "airway or route course changes." 5-3-5. A route does not necessarily have to be found in the enroute structure. Paragraph c. "Consequently, the FAA expects pilots to lead turns and take other actions they consider necessary during course changes to adhere as closely as possible to the airways or route being flown." Nonetheless, that reference was coming from memory, not after reserach.

By "Offical FAA Definition", I mean..SHOW ME WHERE IN YOUR OFFICIAL GOVERNMENT DOCUMENTS YOU HAVE DEFINED " ESTABLISHED ON AN APPROACH PROCEDURE COURSE "
Based on your references, it is anything BUT "...cut and dried...". In fact, you have demonstrated how confusing this issue is.

Show me the definition...
Ok then, after getting off my a$$ and doing some research, pull out a copy of your Pilot/Controller Glossary.

Route - A defined path, consisting of one or more courses in a horizontal plane, which aricraft traverse over the surface of the earth.

Established - To be stable or fixed on a route, route segment, altitude, heading, etc.

If you're looking for something more precise than that (ie: number of dots of deflection, etc.), I seriously doubt that you will find it. There are built in safety margins in approaches, and by making those public, the FAA would be doing a dis-service to pilots. Someone would say "aw, no need to center the needle, we've got x feet of safety margin we can use," and then end up a smoking hole in the ground.

Bottom line is, as was mentioned before, get yourself "established," then descend.
 
bafanguy said:
By "Offical FAA Definition", I mean..SHOW ME WHERE IN YOUR OFFICIAL GOVERNMENT DOCUMENTS YOU HAVE DEFINED " ESTABLISHED ON AN APPROACH PROCEDURE COURSE "
Based on your references, it is anything BUT "...cut and dried...". In fact, you have demonstrated how confusing this issue is.

Show me the definition...
I'm not sure why you are yelling. Are you talking about the definition of "established"? You're not the only one who finds it a problem. I guess a lot of us are looking for every simple English word or phrase to have some "special" FAA meaning. Sometimes they don't.

AFAIK, there's no technical regulatory definition.

Under FAR 91.181, we are generally expected to fly the centerline of any course. In fact the Pilot/Controller Glossary defines "ON-COURSE" as
==============================
"ON-COURSE - Used to indicate that an aircraft is established on the route centerline."
==============================
(There's that word again) Obviously, there are tolerances built into the system since neither people nor navigational aids are perfect.

The closest thing to an FAA definition of "established" is in the AIM/ATC Handbook Pilot/Controller Glossary
==============================
ESTABLISHED - To be stable or fixed on a route, route segment, altitude, heading, etc.
==============================

Hmm. Pretty close to the Merriam Webster definition of "establish"
==============================
3 a : to make firm or stable
==============================

That's good enough for me.

If you're looking for something more precise dividing line like "off the peg" or "within 30 degrees" or some such, you won't find it. And I personally wouldn't expect to see one.

So, are you "stable" on a route when the needle moves off the peg and you begin to make your turn? Or are you "stable" when you complete your turn, the OBS and your flight path (roughly) agree, and the needle is no longer moving (except for normal bracketing corrections)? Or is it somewhere in between?

I think it depends on conditions other than the position of the needle. Let's take a favorite and try it on for size. The "3/4 scale deflection" that is in the instrument PTS as tolerance for the final approach segment on an ILS. 3/4 deflection while turning inbound on a localizer with a bit of headwind so that you can "milk" the turn all the way may well be "established". Blowing through 3/4 deflection twice because of a 40 KT tailwind probably isn't.

I'm satisfied with the English definition. I don't think there's any reason for anything more precise. You can make it more confusing, but you really have to work at it.

Sometimes a cigar is just a cigar.
 
Don't know what I was thinking ... Ususally I check my sources before posting something like this, but my TERPS was elsewhere so I just posted what I tought I remembered. Bad Idea. Anyway. the real answer, now that I've checked my TERPS is that you can descend anytime you are past the fix and are proceeding outbound and have passed abeam the fix, that puts you in the manuvering zone where descent to the procedure turn altitude will give you at least 1000' of obstacle clearance.

Hypothetical approach VOR XYZ to RWY 27. inbound course, 270, barb on north side of course;


Approaching from the west (heading 090) you can descend as soon as you pass the VOR, as you are in the manuvering zone upon passing.

Approaching from the east as you pass the VOR you are in the entry zone, you may not have obstacle clearence at PT altitude, descend after you have turned and have passed abeam (north) the fix outbound.
 
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ACAFool said:
If you are cleared for a vor approach (full procedure) when can you descend to the outbound leg altitude. Is it once you cross the vor or do you have to be established on the outbound radial prior to descending.
It depends on where you are in relation to the outbound course.

Procedure turns are a bit different than other courses. Remember that the barb on a procedure turn only shows which side of the course you are supposed to use for the course reversal, not how to fly it. It's possible to do a proper procedure turn without ever tracking the outbound course.

Example to illustrate. Check out the PUB VOR 26R (http://naco.faa.gov/d-tpp/0410/00334VT26R.PDF) You are southwest of the field and are given the following by ATC.

"Proceed direct Pueblo Akron VOR. Maintain 7,500 until Pueblo. Cleared for the Pueblo VOR Runway 26R approach. "

As the profile view shows, the outbound portion of the turn maybe done at 7,000' and you can descend to 5,500 when inbound.

A traditional "approach" would have you fly to the VOR, turn right to 064° to track the inbound course outbound descend to76,000', fly for a minute or two and then turn left 019°.

But, since the barb =only= tells you that you must do your course reversal north of the 064 Radial and east of the VOR (while staying within the 10 NM distance) you could also go to the VOR, for example, turn right to °019 begin your descent, and then turn to reintercept the inbound course without ever flying outbound at all.

So in this situation if your were going to do the traditional thing, you could descent as soon as you crossed the VOR. But coming from the northeast you might no be able to because, unless you lead your turn, you would probably cross into the wrong side of the final approach course and want to wait until you were on the outbound course before descending.
 
Midlife...


Yelling ? That's possible here ?? Oh, that's right...I forgot...upper case is yelling in email terms. MEA CULPA !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I'm computer/email illiterate so I forgot. I thought I was emphasizing a facet of my point.

And all your points were interesting, but didn't answer the guy's question. What definition YOU ( emphasis again...) are happy with means nothing to the FAA. And I guess that's my point and what makes questions like this so interesting for discussion.

Am I asking the definition of "established" ?? Well, yes Sir. I don't know how to be any more clear about that. It was the gist of the original question.

And, that question remains unanswered...
 
bafanguy said:
And, that question remains unanswered...
To you perhaps. To the FAA, other pilots, and myself, it's resolved.
 
I can cite the exception that proves the rule:

http://naco.faa.gov/d-tpp/0409/09142N13.PDF

Download the NDB 13 For Appleton MN, and pay close attention to the procedure note that is asterisked.

It states that you must maintain 3300 or above until established outbound.

What need would there be to issue this restriction if it was necessary to maintain last assigned altitude until established outbound.

Answer: None.



To understand this issue, you must be familiar with the protected area for procedure turns.

As one previous poster sugested, your ability to descend is based on whther or not you are on the PT side of the outbound course as you turn outbound.

This is not a restriction. You have 4 miles on the NON-PT side before you even hit the secondary obstacle clearance area.

As long as you are going to turn outbound when you hit the VOR, you can descend to the outbound altitude, unless there is a procedure note as shown in the example.

It doesn't matter if you are on the "correct side" (no such thing) of the outbound course. Hit the VOR, start your turn and descend.


Now, you MUST be on the correct side when you do the PT, because it is assumed that you are leaving the course to essentially dead reckon your PT.

You have 8 miles of primary protected area to the side of the course at the ten mile outer limit. At the IAF, you have 6.

On the 'non-protected' side, you have 4 miles all the way out to the ten mile limit.

If I can find a pic of the PT template, I'll post it.
 
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Philo,

You know, what I posted first (before the editing and backtracking) was essentially what you posted here ... then I read the relevant TERPs section, and saw it differently, and decided to edit my post, now im reading your post and I see the compelling logic in your "exception which proves the rule". D@mn.... I wonder if this is what Kerry feels like.
 
Keep it simple! Answer the original question.

ACAFool said:
If you are cleared for a vor approach (full procedure) when can you descend to the outbound leg altitude. Is it once you cross the vor or do you have to be established on the outbound radial prior to descending.

Thanks
If I understand your quote correctly, I'll assume you mean a procedure turn after crossing a VOR. Look at the VOR on the approach plate, it should have (IAF) under the name of the fix. (IAF), you are established on the approach phase, you are cleared to descend.

Remember the 5 Ts:

Turn
Time
Twist
Throttle (retard and descend)
Talk

I hope that answers your question.
 
bafanguy said:
And, that question remains unanswered...
Only if you want it to be.

==============================
ESTABLISHED - To be stable or fixed on a route, route segment, altitude, heading, etc.
==============================

seems about as simple and understandable as it can be.
 
When you hit the VOR and start to turn, you are established on that segment. That is why they give you 4 or more nm of protection in the primary area alone.

Check out that plate for appleton again. Why the procedure note if being established on the RADIAL was always a condition of descent?

Being established on a radial and being established on a segment of the approach can mean two different things.

To be fair, I believe that the military requires their pilots to be firmly on the radio prior to descent, but that does not prove anything about civilian regulations.

Point of order: If you are established on an airway that bends sharply at a vor and overshoot the new radial, are you temporarily not established, requiring you to consider the sector altitude? I think not.


Here's a question for all of you:

When do you report "established in the hold"?

A. When you first cross the holding fix.
B. When you turn outbound
C. After completing the entry on your first inbound leg
D. After you get the 1 min inbound all worked out


And to clarify the point again, you may descend regardless of the direction from which you arrive at the IAF. There is no "wrong" side when turning outbound, so no worries about overshoot. Personally, I lead the turn by about .7-.9 dme if available jsut to make a clean intercept. But then, I usually make a hold-type entry instead of the standard PT, since it is sompler and a more elegant solution than the dull axe that is the PT.

Caveat: Hold type entries do not work as well if there is a lot of altitude to lose outbound or inbound.
 
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ACAFool said:
If you are cleared for a vor approach (full procedure) when can you descend to the outbound leg altitude. Is it once you cross the vor or do you have to be established on the outbound radial prior to descending.

Thanks
It's rather amusing to see all the twists and turns the answer to this simple question can take.

To begin with, let's assume that ACAFool intended to specify a Procedure Turn type of Instrument Approach Procedure, as opposed to a teardrop approach or procedure track of some sort. If so, then there IS no "outbound radial." The procedure turn has an INbound Course, and a manuevering side.

Examine the question further, and notice the poser asks a multiple choice question:

Is it (A) once you cross the vor or (B) do you have to be established on the outbound radial prior to descending.

Since we've already established that there is no outbound radial, the answer must be (A)!


:)




.
 
Midlifeflyer,


Okee, dokee... was just trying to have a little shoptalk with fellow aviators on an interesting technical issue. MEA CULPA !!! ...oops, mea culpa...

I still seriously doubt a dictionary definition suffices for an area where things are so carefully defined ( legally and technically ) as they are in instrument flying. But...that's just one guy's opinion.

ASquared seems to have a handle on the TERPS stuff.
 
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bafanguy said:
I still seriously doubt a dictionary definition suffices for an area where things are so carefully defined ( legally and technically ) as they are in instrument flying.
In other words, it depends on what the meaning of "is" is? ;)

That English thing? There's an awful lot of it going around.

ATC: Climb and maintain 8 thousand feet.
Pilot: What do you mean by "feet"? I can't find a definition in the FAR! Nor can I find definitions for "climb", "maintain", "eight" or "thousand". How do you expect me to know what to do?

:D
 
Now THAT'S funny!

Obviously, there are tolerances built into the system since neither people nor navigational aids are perfect
I think the answer is hinged on this statement. The reason that no defined numbers or tolerances are published regarding what is ESTABLISHED is because, as it was stated, it's human nature to bend the rules. So when a particular approach is developed, the courses, routes, and altitudes have to be established with a degree of "fudge factor".
I used to tell my students to not fixate on hold entries, "you're gonna be disregarding aviation rule NO.1, you'll be trying to hold the "Vulcan Peace Sign" over the DG with one hand and have a note pad, pencil and caculator in the other and in the mean time, will be flying into some mountain because you've blown past the holding fix."
If I am approaching the holding fix directly from the direction of the inbound leg and decide to do a PARALLEL entry instead of direct "there won't be an FAA helicopter there waiting to give me a ticket!"
In my opinion, the question has been answered. You may descend once Established(as defined), unless other specifics of the particular approach have otherwise been published(as has been discussed).
 
The relevant crash was in the 70's, an arrival to Dulles, I believe. 727 or -9. Eastern? Accident aircraft was cleared for approach while still a ways out. And was not yet 'established' on any published segment of the approach procedure. And terminology back then was simply "cleared for the approach". Descended into terrain.
Once cleared the approach, can descend when "established" on published segment of the approach procedure for which a lower altitude is published. "Established" is not precisely defined anywhere by reference to instrument indications and will depend in part upon intercept angle, aircraft speed, wind speed/direction, etc., which in turn will affect the speed at which the needle is moving/centering, assuming there is a needle/CDI involved. Also, on whether it's a localizer or a less sensitive directional system. The biggie here I think is the published approach segment.
The Terminal Arrival Area descriptions in the AIM look interesting. (e.g. Figures 5-4-7, 5-4-8).
 
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lawfly said:
..............."Established" is not precisely defined anywhere by reference to instrument indications and will depend in part upon intercept angle, aircraft speed, wind speed/direction, etc., which in turn will affect the speed at which the needle is moving/centering, assuming there is a needle/CDI involved. Also, on whether it's a localizer or a less sensitive directional system. ................
That's the point that I was trying to make with my obtuse FAA helicopter scenario.
I wouldn't want to intentionally make a 210 degree turn away from the fix towards the the "unsafe" side of the holding course. On the same token, there aren't complete dimensions for a holding 'racetrack', beyond leg distance and overall approach tolerances(MSA, MOCA, "do not exceed XX DME" notations) either. If I DO have a strong tail wind as I cross the fix or if I enter the hold from the direction of the dividing line for the parallel/direct sectors or am unfortunate enough to encounter both elements at once.........I may be flying a minute or so out in "unsafe side" land before I can become ESTABLISHED.

I may allow for a degree of tolerance as far personal standards for hold entries but if this same hold is associated with an approach, of course I will lead a radial but I'm not going to DESCEND until the needle is centered.
 
That is a common technique, but is not required. Most folks I know use a live needle.


Me, I use station passage plus a turn outbound.

4nm is a lot of real estate.
 
Uncle Sparky said:
Now THAT'S funny!

I used to tell my students to not fixate on hold entries, "you're gonna be disregarding aviation rule NO.1, you'll be trying to hold the "Vulcan Peace Sign" over the DG with one hand and have a note pad, pencil and caculator in the other and in the mean time, will be flying into some mountain because you've blown past the holding fix."
If I am approaching the holding fix directly from the direction of the inbound leg and decide to do a PARALLEL entry instead of direct "there won't be an FAA helicopter there waiting to give me a ticket!"

Your student's will be fine unless they happen to be in a simulator for an airline interview.

I do agree with what you are saying, I am amazed that anyone can actually draw a hold entry out while still keeping the shiney side up. I have never drawn a hold in my life except as a flight instructor during initial holding ground.
 

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