Altitude restrictions

[Sink Rate]

May I pose a question to you all as to altitude restrictions on SIDS and STARS?
If say you are flying flying a STAR and the controller clears you down to, say FL180, level by ABCDE.

You look at the plate and it says "thou shalt be at ABCDE AT FL180". Easy so far.

If then ATC clear you down to FL140, before you have reached ABCDE, are you still then expected to meet with the AT FL180 AT ABCDE restriction and then continue descent to FL140?

I think not, but some of the guys I fly with seem to think so, others aren't sure. Also vice versa with a SID and climb clearances.

What are your opinions of this. I am especially interested to know what our TC controllers think/know!?

Thanks in advance.
SR

[Buffy Summers]

I believe its the same whether SIDs or STARs - you should ask if "unrestricted" climb or descent. ie. climbing on SID, have to cross point A at 3000 feet, ATC clear you to FL160 (unlikely, I know), your reply should be "confirm climb UNRESTRICTED FL160?". However, I also think that ATC is meant to say "climb/ descend "unrestricted" XXX".
Perhaps a controller can confirm?

[TinPusher]

Unless the restriction is cancelled formally I would expect you to still comply with the Fl180. The only time I would expect you not to meet the restriction would be if you were stopped off at Fl190 or above.

[Sink Rate]

Is there anything formally written down regarding this matter. It seems that so far it is personal opinion as to what restrictions apply.

Any other controllers care to comment? (Perhaps someone from CATC?)

[PPRuNe Radar]

Sink Rate,

In the UK, level restrictions on STARs are placed there for flight planning purposes so that crews may plan their descent profiles and fuel loads. They are not cleared levels and there is a plain language message on the STAR charts which states that actual levels will be assigned by ATC.

Now if ATC have cleared you down to FL180 level by ABCDE (which matches the published profile on the STAR) and then subsequently reclear you to FL140 by VWXYZ but do not mention the original restriction, then that original restriction is automatically cancelled.

SIDs are subtley different in that the restrictions published in them are actually part of the ATC clearance (a SID is in fact just an ATC clearance which is charted to cut down on RT). These restrictions are placed there to ensure terrain clearance, noise preferential routeings, and ATC procedures are all complied with.

Strictly speaking, ATC clearing you above the SID final altitude would by default cancel all other restrictions in the SID, however as the pilot you are still responsible for ensuring that you follow the noise preferential route (and altitude elements) plus maintain terrain clearance. As most pilots are busy after departure I would imagine they would just continue with the SID restrictions rather than work out for themselves the levels they need to be at to ensure compliance.

Examples of SID & STAR charts from the AIP can be found here. Just pick the airfield you want. The references to levels, NPRs, and climb gradients for terrain purposes are contained within the notes of each chart.


http://www.ais.org.uk/uk_aip/pdf/ad/aipad2.pdf

'Unrestricted climb/descent' is not in UK pharaseology.

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PPRuNe Radar
ATC Forum Moderator
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[gaga1976]

On STAR, if after "...descent FL180 by ABC" we get "...descent FL150 by XYZ" it is clear to disregard first restriction. What happpens when second clearance is just "...descent FL150"?
If after "...descent FL180 by ABC" we get radar vector (from "present hdg to left/rigt 90*) are we to be given level abeam given point (hard if hdg change is big)?
For SID: In UK we have altitude restrictions on chart and initial level is not given in Clearance-pre-taxi (you take it from chart). In other places like Madrid, Rome... there are max altitudes on chart (at or bellow), and clearance altitude is higher. You can climb clearance level only passing these points. Does the departure ATC clearance above these altitudes before these points cancels SID restictions?

[Grandad Flyer]

PPrune Radar, I love this forum, I learn so much!
Anyway, here is a question about SIDs. Lets take the STN CPT 3R as an example. There are two stop heights, both 3000 feet (for historical reasons I suspect), one before BKY and one after BKY. We almost always get cleared to FL70 prior to these points, then generally we will get radar vectors at some point further on, but we always go for an "open Climb" which means we don't stop at the stop heights. We do usually say "climb unrestricted" but now you have posted your reply above, I think we are doing this wrong and should maintain the 3000 feet limit until we're past the second (post BKY) stop height and then climb to FL70. We always follow the SID laterally.
It has never been queried by ATC.
Its not a problem either way for us to do in the aircraft.

[identnospeed]

G'dad Flyer,

Clearance to FL70 is unrestricted in the case you mention. If a controller wanted you to comply with the the SID altitudes as per the plate, then he/she would not clear you to FL70 in the first place.

We get a lot of US pilots asking the same type of question. This is due, I believe (?), to the nature of American SIDs where a clearance on a particular SID requires the a/c to follow the particular profile stated and aircraft are not generally authorised by ATC to deviate from that profile.

Sink Rate,

With regard to STARs : you may be istructed to be FL200 level 20nm before ABCDE and later told to be FL150 level ABCDE. The book says that the ATCO must restate the previous restriction if he/she wants you to still comply with it.

In practice this is never done.

Due to the requirement to fly standard speeds unless otherwise instructed, which involves a speed of 250kts at, say, ABCDE; most a/c need to be at FL200 level 20nm before ABCDE in order to make the 150 level by ABCDE AND reduce to 250 kts by that point.

Almost all the STARs into the LTMA are constructed in this way. And if you ended up being 200 level 17 miles before ABCDE (ie. 3 miles late) I don't think any radar controller would notice.

These STAR restrictions are usually designed to avoid you entering the airspace of a controller who has no information on your flight. However, they are generally not so tight as to be dangerous if missed by a mile or two.

INS

[PPRuNe Radar]

Grandad Flyer,

Sorry, I was not as precise as I should have been. When I was talking about pilots still complying with SID restrictions even when cleared above the final SID altitude I was thinking more about the cross at or above levels rather than the stepped climb ones.

For the stepped climb ones, identnospeed has hit the nail on the head, the restriction has been removed and therefore you may climb on the vertical profile as you see fit, subject noise and terrain constraints.

That should be all the angles covered now ;)

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PPRuNe Radar
ATC Forum Moderator
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[TinPusher]

It never ceases to amaze me that when most of the worlds procedures are based on the same ICAO recommendations there is still so much conflict of opinion on matters that are really very important.

In Sink Rates original scenario a published (standard) restriction is reiterated by ATC ie Be level FL180 by ABCDE.ie He/she wants you to comply. Subsequent descent to FL140 is NOT a restriction, it is issued to prevent the acft leveling at FL180 when there is no need to do so. In my opinion the original restriction still applies!

Where the 'Be level FL180' is followed by a further restriction, as in gaga1976's scenario, where a further restriction is added then the original restriction is cancelled unless ATC reiterate.

Pprune radar, I agree that level restrictions on STARS are not cleared levels, however if cleared levels are issued that will enable the flight to comply with the STAR profiles (as they should 90% of the time or there is little point in having STARS) then it should be a valid expectation that the flight will comply unless they are specifically cancelled, in the same way that speed restrictions and max entry levels to holding patterns should be complied with unless ATC has issued a specific clearance to disregard what are standard procedures.



[This message has been edited by TinPusher (edited 03 September 2000).]

[PPRuNe Radar]

TinPusher,

Part of the problem is that ICAO procedures are very generic and never go into the level of detail which States tend to publish for their specific operation. Their advice on reclearances tends to cover changes to flight plans, destinations, etc. There is nothing I can find on the scenario we are discussing. Also looking in the ICAO documents for phraseology terms, there is no ICAO phrase such as that suggested by Buffy, the only vertical reclearance phrases are 'Stop climb/descent' or 'Recleared'.

Both the UK and US procedures are quite specific however, and that is that all restrictions for a particular element (level, speed, time or route) are cancelled in a reclearance of the same element.

In Sink Rates example the descent clearance to FL140 is a reclearance, replacing the original clearance which was FL180 level by ABCDE. The fact the original FL180 was given as a restriction doesn't change the fact it is a clearance whether stated explicitly by ATC or as part of a published SID/STAR on which the aircraft has been cleared (these types of routes are just documented ATC clearances after all).

Unfortunately I don't follow your logic on restrictions I'm afraid. I apologise if I've misunderstood. What you seem to say is that if the aircraft has a restriction A (lets call it FL180 by ABCDE) and is then given a reclearance to FL140 with no restriction stated, then you still expect the pilot to comply with restriction A. Yet if he is given restriction A, but instead of a free descent is given a descent to FL140 level by VWXYZ (i.e. restriction B), you would only expect restriction B to be complied with. What's the difference such that restriction A is assumed to be cancelled in one case but not the other ?

In the UK and the USA, there should be no doubt. The controller is required to reiterate the restriction if they want it to apply. Now, what many people do in my experience is to monitor the profile being followed and issue the reclearance when it is obvious that the aircraft is going to make the restriction anyway. So we do not physically reiterate the restriction, but manage the traffic profile so that it complies anyway. This echoes what identnospeed says.

I think your last point will very much depend on what the STAR chart says. For the UK, the published levels are for guidance. If the controller wants the pilot to comply with them then they have to pass that as part of the clearance. It would not be good enough for us to simply clear the pilot to FL180 and then expect them to cross ABCDE at that level as per the chart, because that is not what we have cleared the pilot to do. Other countries may have different procedures and have 'hard' altitudes on the chart. In those cases what I have heard is the pilot being cleared to follow the STAR 'with the profile'. No descent clearance is passed and the pilot is expected to follow the route both laterally and vertically.

As to why have STARs ?, again from a UK viewpoint, the prime purpose is so we know where the aircraft are going to fly laterally. The vertical elements are enshrined in ATC procedures such as Standing Agreements between sectors or airfields so when it's busy the profile will be followed by the clearances issued, rather than the pilot being cleared to follow the profile on their own. However these vertical profiles, which are often not ideal in economy terms, are relaxed when traffic permits. In fact sometimes in the quieter periods the controller will be working both the sectors for which the profile has been designed (for ATC co-ordination purposes). So unless they have a split personality (mmmmm, in ATC that is quite possible !!), the restriction can be lifted and usually is, saving the crews a couple of Kg of fuel.

I agree with you that speed restrictions should be adhered to, but that is because the controller has generally not varied or lifted them. In the examples we are talking about the levels have been varied by ATC, thus overriding any restrictions.

Now we've got Grandad Flyers attention, I hope this lot doesn't scramble their brain too much :)

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PPRuNe Radar
ATC Forum Moderator
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[Grandad Flyer]

You guys and girls in ATC always have my full attention :)
Basically you have just confirmed what I always thought was the case, and cleared up my error on "unrestricted" climbs.
Now, lets throw one more spanner in the works.
Why IS it that some pilots insist on saying "Charlie Charlie" instead of "affirm". I looked in my reggie spotters radio telephony manual and couldn't find it in there.
I think it might be an ex-RAF pilots thing.
I hear it ALOT on the Casablanca sector.
Please can someone confirm that this is non standard - we are always being lectured to about non-standard RT in our company and I would like this to be sorted.
Thanks!

[PPRuNe Radar]

Grandad Flier

'Charlie' is definitely non standard, as is 'squawk coming down', 'out of 2 point 3 for 6', etc, etc.

Whilst these sorts of phrases may have their origins in days of old, the old tricks are passed on to the young ones coming through the system and so live on well past their sell-by date http://www.pprune.org/ubb/NonCGI/frown.gif



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PPRuNe Radar
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[Sink Rate]

Thanks PPRruNe Radar et al.
That has just about cleared up my question (even if it did take me a bit of time to work through it!).

As soon as my head stops spinning I shall go to work and put in into practice!

Cheers!



[This message has been edited by Sink Rate (edited 05 September 2000).]

[TinPusher]

I've been prompted to a little research and found that in NZ there is nothing published concerning this scenario, apart from a few phraseologies that apply to reclearances.

PPrune radar, I dont follow my logic either although I am sure I had a point...perhaps it was my other personality. http://www.pprune.org/ubb/NonCGI/eek.gif

Whilst our manuals may be lacking, an informal survey amongst my collegues resulted in a 60/40 split on opinion, with the majority expecting the aircraft to be somewhere close to the published level anyway. Assuming the restriction is necessary it will be for a reason (read traffic) and where there is potential for doubt, good operating practice would dictate a confirmation or reiteration.
There are new FMS STARS soon to be published for Auckland that will have 'hard' altitudes published but they are all not belows for noise abatement and there is a comment stating that they are mandatory.

Here's another scenario:
SID has maintain 3000 to 10DME, the route clearance has cross 35DME 11000 or above. Aircraft calls airborne climbing 3000, is identified and given climb to cruise level (FL330). Does the 11000 by 35DME still stand??? I think it does given that the SID finishes at 10DME but there are some who disagree ie, give climb and you cancel previous instructions, including the 11000 by 35 (The SID and route clearance are published as Standard Route Clearances eg CHAA3)
This sort of stuff gives me a head ache http://www.pprune.org/ubb/NonCGI/confused.gif http://www.pprune.org/ubb/NonCGI/confused.gif


[This message has been edited by TinPusher (edited 07 September 2000).]

[karrank]

The variety of views here is quite frightening! My experience in OZ on flight-deck famil at least encourages me that a cross section of OZ pilots understand the procedures.

Consider a STAR (which is also an ATC clearance which is charted to cut down on RT) with "reach FL180 by PRANG". For a start I would not re-state the requirement with a level assignment, the pilot has it already.

Even without a STAR I am most unlikely to assign "descend to FL180 reach FL180 by PRANG" unless I want the aircraft to maintain, or there is something else in the way. If I then assign FL140 (without a requirement) the previous requirement STANDS.
If I want to impose an additional requirement I must prefix it "additional requirement" or 180xPRANG is cancelled. So, with the above STAR:

"Descend to FL180," means "descend to FL180, reach FL180 by PRANG."

"Descend to FL140," means "descend to FL140, reach FL180 by PRANG."

"Descend to FL140, reach FL140 by AUGER," means "descend to FL140, cancel PRANG requirement, reach FL140 by AUGER."

"Descend to FL140, additional requirement, reach FL140 by AUGER," means "descend to FL140, reach FL180 by PRANG, and reach FL140 by AUGER."

Finally, (if anybody is still reading) I understand CC is an old morse thing, certainly beloved of Asian Aeradio operators.



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"Station calling Centre, grow a head..."

[gaga1976]

I still do not know if I agree with the way Karrank sees things about STAR restrictions but I LOVE the way he had put it. It's clear and concise.

"Descend to FL180," means "descend to FL180, reach FL180 by PRANG."
-All clear

"Descend to FL140," means "descend to FL140, reach FL180 by PRANG."
-This is the way 90% of people would do. Even if not correct, it's on a "safe" side and ATC won't bug you about it (you only burn few more kilos of fuel). I see CaptPPRuNe doesn't agree on this one

"Descend to FL140, reach FL140 by AUGER," means "descend to FL140, cancel PRANG requirement, reach FL140 by AUGER."
-Agree

"Descend to FL140, additional requirement, reach FL140 by AUGER," means "descend to FL140, reach FL180 by PRANG, and reach FL140 by AUGER."
-Never heard that one. It would be to much from ATC to expect we want to deal two restriction at the same time. There are other things to think during descent (weather, terrain, cabin rate...)

Q to you Karrank:
"Descend to FL180 by PRANG"
"Direct AUGER, descent FL140"
Does that means?
"Direct AUGER, descent FL140, be FL180 abeam PRANG" or
"Direct AUGER, descent FL140, cancel FL180 restriction by PRANG"

[Sink Rate]

It's a minefield again! I'm not sure what I believe anymore!

[LoLevel]

Star Requirement to Cross GUDIT not above 10000FT.

ABC when ready descend 8000, QNH blah blah.
Rog..
ABC descend 6000.

I am expecting you to still cross GUDIT BLW 10000, cos there is a good chance that level dovetails with a SID cross of FL120 or something similar. Even though on Radar it will be monitored I would still be expecting the ACFT to toot if he/she ain't gonna do it.



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"The views expressed here are a personal rant and rave and in no way reflect the views of my employer/s "

[PPRuNe Radar]

Sink Rate,

In the UK (and the US, which is unlikely in your fleet !!), it is perfectly clear. Restrictions are cancelled with any subsequent clearance UNLESS they are restated.

gaga1976

I have no problem with people complying with restrictions in charts even when they have been cancelled......the only pain is on the airlines fuel bill, possibly.

karrank

Oz seems totally different, including the phraseology....but then they also have TAATS !! ;) Fortunately ASA have been ruled out of the bidding to buy the UK ATC system so this old dog will not have to learn new tricks ;)


I vote the two busiest air traffic nations in the world get ICAO to adopt their standards, all in favour say aye !!



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PPRuNe Radar
ATC Forum Moderator
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[gaga1976]

LOLEVEL,
What if, before reaching POINT you give me "Maintain present hdg". I'm still gonna overfly POINT but technically I'm not on STAR.
Or "Direct XYZ". POINT goes out of my FMC and putting it back (abeam) takes few strokes.

PPRuNeTower, is there a piece of paper that I can quote to my Captain next time on UK Star

P.S. Last time when I said CaptPPRuNe, I meant PPRuNe Tower. Sorry

[PPRuNe Radar]

gaga1976

The instruction for controllers is found in the Manual of Air Traffic Services (MATS) Part 1 (CAP493). I don't have one to hand to give the exact reference but will advise shortly. Unless of course one of my learned colleagues jumps in first. In the meantime, any UK AIP published STAR will provide the Captain with the following:

DESCENT PLANNING

Pilots should plan for possible descent clearance as detailed in the table below. ACTUAL DESCENT CLEARANCE WILL BE AS DIRECTED BY ATC

For example, Bovingdon STARs to Heathrow

http://www.ais.org.uk/uk_aip/pdf/ad/32LL0702.pdf


There is no corresponding entry in the UK AIP that I can see to relate to the MATS entry, nor is it repeated in the ICAO documents. However it does also appear in the US ATC manual, which is available on the web from the FAA site. I don't have a CAP413 (RT Manual) to hand either to check that, but will in a day or so.

Perhaps it would be prudent for the CAA to put the text from the MATS Part 1 in the AIP and then it is clear for all to see on both sides of the mike........in UK airspace at least.

PS PPRuNe Towers is not Captain PPRuNe but nor is he PPRuNe Radar. I'm the one they keep down below in the darkened room.

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PPRuNe Radar
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[This message has been edited by PPRuNe Radar (edited 09 September 2000).]

[gaga1976]

PPRuNe Radar,
Operationally it doesn't make much difference that this Altitude Restriction is only for planing purposes since it can be issued any time during descent and you have to be able to make it, preferably without extending gear or speedbrake (I've heard they call it 'shamestick' in Australia).
Yesterday I flew to LGW and we had to descent to be FL160 by BEXIL even before the actual clearance was given to be able to make it when the clearance was given.
Also would like to hear your opinion about
"Descent FL160 be level at BEXIL" compared with
"Descent FL160 by BEXIL" (as in UK STARs)
Is it same thing?

[PPRuNe Radar]

gaga1976

Most ATC'ers have a fair idea of the normal profiles generally flown in order to meet restrictions. So in the main, descent clearances will be given in sufficient time to make good any ATC imposed restriction. This can either be by ATC instructing you to descend now, based on their knowledge of profiles, or as a 'descend when ready' instruction which leaves it up to you to make the move at the right time.

The BEXIL instruction you quote is the same. One is a written version, the other is the RT phraseology required to say the same thing. There are 2 phrases which can be used on the RT.

Descend FL160 to be level by BEXIL, or,
Descend FL160, cross BEXIL level.

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PPRuNe Radar
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[PPRuNe Radar]

gaga1976,

There is no entry in the CAP 413 (RTF Manual) regarding reclearances and previous restrictions.

The MATS Part 1 (CAP493) quote for your Captain is from Page 1-27 Para 6 which says:

AMENDMENTS TO CLEARANCES

When an amendment is made to a clearance the new clearance shall be read in full to the pilot and shall automatically cancel any previous clearance. Controllers must be aware, therefore, that if the original clearance included a restriction, e.g 'cross ABC FL150 or below' then the issue of a revised clearance automatically cancels the earlier restriction unless it is reiterated in the revised clearance'

Anyone out there with contacts in SRG Flight Ops who could ask what they think ??

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PPRuNe Radar
ATC Forum Moderator
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[karrank]

For GAGA1976:

Multiple requirements do have a place apparently, I've never tried though, If I have more than one I would usually do them one at a time while assigning an intermediate level, but it is in our manual.

If STAR = Reach FL180 by PRANG (60NM from IMPACT)

"Track direct AUGER, descend FL140, reach FL180 by 60 miles from IMPACT."

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"Station calling Centre, grow a head..."

[Eric T Cartman]

Along the same lines as the above, would someone care to offer an opinion on the following for me, as an Approach man who hasn't done Area Radar for 26 years & who has already had several conflicting answers!
Traffic inbound to VOR XYZ on Radar Release/Handover, descending to min stack e.g. FL70. Centre gives handover, saying traffic descending to FL70, to be level 10 miles before XYZ.
(Perhaps to deconflict traffic inbound XYZ from a different direction allocated FL80, or standard practice anyway ?)
On first contact, I descend the aircraft to 6000ft altitude. If I have not been given any information on conflicting traffic can I & / or the pilot assume that the restriction is now cancelled, or, as PPrune Radar quotes from MATS Pt.1, should the clearance now be "descend to altitude 6000ft, to be FL70 or below 10 miles before XYZ" ?

-------------------------------------------
Damn, I got old quick !

[This message has been edited by Eric T Cartman (edited 14 September 2000).]

[PPRuNe Radar]

ETC,

If you accept the handover with a restriction, then you must ensure that the restriction is met. So according to MATS Part 1, you need to repeat that restriction if you issue a reclearance. If you don't then there is nothing to prevent the pilot ignoring it.

However, in practice, what you might do is assess that the aircraft will comply by default when you issue the new clearance and so not bother.....but be aware that the responsibility for making sure the pilot does meet the restriction will be yours !!

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PPRuNe Radar
ATC Forum Moderator
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[Eric T Cartman]

PPRuNE Radar
Thanks for the above.
I understand what you're saying about a radar handover but as our traffic is always on a "radar release", MATS Pt.1 requires that conflicting aircraft are either transferred to me or identified, according to my decision. So, if no confliction is notified to me, I wonder why the level restrictions are imposed in the first place?
Also, once the aircraft hes been released to me, if no confliction is notified, I may vector it away from XYZ towards final approach & it would therefore be impossible to comply with the "level 10 before" restriction !

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Damn, I got old quick !

[gaga1976]

PPRuNe Radar,
Thanks for the answer. Only Hard Evidence matters when you have disagreement in cockpit.
It is my opinion that knowledge about this got lost in everyday operation. Pilots are doing original restrictions even when it's not repeated because they are not quite sure, and since they always do, ATC slowly forgot it needs to repeat it. And as we all know not many people bothers to go through books again from time to time. Especially if the things are going well.
I think thing are clear for UK airspace. Is there anybody from other European ATC who would like to comment?

[gaga1976]

Are forementioned documents (CAP & MATS) by any chance available online?

[StopStart]

Stumbled in here after following a link from the Tech Log - lots of good gen here.
Grandad Flyer asked a question a few days ago re: "Charlie Charlie" instead of "affirm"; I've been told by various old and bolds that it dates back to the days of the early days of HF radios. I certainly use it a fair bit (RAF I'm afraid) in the Middle East and Africa - controllers 'round those parts will often say "Is that Charlie?" (instead of "Is that correct?") the reply to which is "Charlie Charlie". Hmmm.

[10W]

Been following this one closely. I've spoken to some people in SRG who are going to get back to me with where it appears in UK pilot documentation. I suggested it should maybe be in the UK AIP, so who knows !! Watch this space.

Sorry gaga, don't think the documents are available online yet, but again there is progress being made by the CAA to come into the 21st Century and maybe one day they will be there for all.

In the meantime I'm sure some of us here can forward photocopies of extracts to those who need them.

Cheers

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10 West
UK ATC'er
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[Sink Rate]

I need them 10W!

I'll be very interested in what SRG will have to say. This is certainly not something that is covered clearly in any one publication that I am aware of. It's an important issue, and one that I'm sure we would all like to see resolved in official documentation.

I appreciate that many of you guys know the rules, mostly learned at CATC, but to have it in a quotable written form would be invaluable.

[10W]

Sink Rate,

Drop me your e-mail address and I'll send you a PDF of the relevant bit.

Cheers

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10 West
UK ATC'er
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[Chatterbox]

I just hope that no one flying out of LHR on the BPK sid decides that when they are cleared to FL130 thinks they can ignore the min alt restrictions on the sid. If they do it's all gonna get a bit messy around CHT when ya meet the NHT outbound. Surely unless told otherwise any level restriction, be it "level by" or "at or above" etc will be ignored without at least queerying it.

[On the air]

Hello!

In Germany we do it in this way:
If we gave you a level combined with a restriction then comply with it until we call you: disregard the restriction
To stay with the example
cleared level 180 to be at PRANG
if you get the reclearance : descend fl 140
then comply with the previous restriction until we call you: disregard
if you get the clearance: descend Fl180 with 2000ft/min which would make you to cross PRANG at Fl180 then the restriction is not further mandatory when recleared to FL140
unless I call you to keep the rate of descent

in general: if there is a restriction made with a point or FL then comply with it unless we say disregard (even if you are sent to another frequency).
If we clear a FL with rate of descend/climb then you can disregard the rate as soon you get a new FL.
Comply with restrictions of STARs/SIDs . If it is not possible (only due to aircraft/weather reasons) to comply with, inform us . Our clearances normally take care on the restrictions on the chart.
restrictions in STAR/SID are made for noise abatement and for radio com failure only!
:)

[10W]

Sink Rate,

Copy of UK ATC instructions in the e-mail for you.

The US ATC manual and other FAA Air Traffic publications can be found here:

http://www.faa.gov/atpubs/default.htm

or to quote direct from the FAA Manual Doc 7110.65 Chapter 4 Section 2 Para 4.2.5:

b. When route or altitude in a previously issued clearance is amended, restate all applicable altitude restrictions.

EXAMPLE-
(A departing aircraft is cleared to cross Ollis intersection at or above 3,000; Gordonsville VOR at or above 12,000; maintain FL 200. Shortly after departure the altitude to be maintained is changed to FL 240. Because altitude restrictions remain in effect, the controller issues an amended clearance as follows):

"Amend altitude. Cross Ollis intersection at or above Three Thousand; cross Gordonsville V-O-R at or above One Two Thousand; maintain Flight Level Two Four Zero."

(Shortly after departure, altitude restrictions are no longer applicable, the controller issues an amended clearance as follows):

"Climb and maintain Flight Level Two Four Zero."

NOTE-
Restating previously issued altitude to "maintain" is an amended clearance. If altitude to "maintain" is changed or restated, whether prior to departure or while airborne, and previously issued altitude restrictions are omitted, altitude restrictions are canceled, including DP/FMSP/STAR altitude restrictions if any.


The US pilots guidance, contained in the Aeronautical Information Manual states:

Chapter 4 Section 4 Para 4.4.4

g. The guiding principle is that the last ATC clearance has precedence over the previous ATC clearance. When the route or altitude in a previously issued clearance is amended, the controller will restate applicable altitude restrictions. If altitude to maintain is changed or restated, whether prior to departure or while airborne, and previously issued altitude restrictions are omitted, those altitude restrictions are canceled, including departure procedures and STAR altitude restrictions.

EXAMPLE-
1. A departure flight receives a clearance to destination airport to maintain FL 290. The clearance incorporates a DP which has certain altitude crossing restrictions. Shortly after takeoff, the flight receives a new clearance changing the maintaining FL from 290 to 250. If the altitude restrictions are still applicable, the controller restates them.

2. A departing aircraft is cleared to cross Fluky Intersection at or above 3,000 feet, Gordonville VOR at or above 12,000 feet, maintain FL 200. Shortly after departure, the altitude to be maintained is changed to FL 240. If the altitude restrictions are still applicable, the controller issues an amended clearance as follows: "cross Fluky Intersection at or above three thousand, cross Gordonville V-O-R at or above one two thousand, maintain Flight Level two four zero."

3. An arriving aircraft is cleared to the destination airport via V45 Delta VOR direct; the aircraft is cleared to cross Delta VOR at 10,000 feet, and then to maintain 6,000 feet. Prior to Delta VOR, the controller issues an amended clearance as follows: "turn right heading one eight zero for vector to runway three six I-L-S approach, maintain six thousand."

NOTE-
Because the altitude restriction "cross Delta V-O-R at 10,000 feet" was omitted from the amended clearance, it is no longer in effect.

ICAO does not appear to have any such guidance, maybe its time it did ??



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10 West
UK ATC'er
[email protected]