Clearance Clarification Clarence

[autopilot_off]

Hi All,

I had this one today for the first time and was wondering if one of you ATCO's could clarify it for me?

The clearance was "Descend FL150, when level speed 220kts"
As we passed through FL160 we were further cleared down to 80.

Are we expected in this case to slow to 220 as we pass through FL150 or to maintain speed and slow when level at 80?

We were on one of the London frequencies at the time and as I'm sure you know we couldn't get a word in to clarify so we dropped to 220kts at FL150 and nothing was said.

Was that what was expected or does the "when level" bit then apply to the new level?

Thanks in advance.

[ZOOKER]

Any ATC clearance cancels the previous clearance.
Unless the controller stated otherwise, I believe the speed restriction no longer applied.
If you couldn't get a word in, possibly, the sector/frequency needed 'splitting'.

[ab33t]

I believe what you did is correct , speed applied to FL150 and you did pass through and Im sure there was a reason for the speed . The new instruction applied to flight level

[jackieofalltrades]

Any ATC clearance cancels the previous clearance.


What Zooker says is correct, however, I would still expect you to slow to 220kt at FL150 unless you were explicitly given another instruction regarding speed. By the book the controller should have reiterated the speed restriction when you were cleared to FL80, but being busy and having it in his/her head that they've just instructed you to fly 220kt, it wouldn't be something they would necessarily think to say again.

[Knackers]

It's a poorly phrased clearance if it leads to so much doubt.

[Pera]

Any ATC clearance cancels the previous clearance.

Better restate the airways clearance with any change of level then. :ugh:

[tczulu]

As an old git with 25 years experience as a LTMA controller,I drum this point into every trainee, that they should restate the speed restriction required if further descent is given before the previous level is reached.On a busy frequency,the last thing required is ambiguous phraseology leading to more transmissions to clarify exactly what the controller expects thecrew to do.Time to retire methinks!

[bekolblockage]

Thats why I just don't get this interpretation.
What if the restriction was assigned by a previous controller, then handed off, legitimately without any coordination, why should you reiterate it? You may have no knowledge of it.
Surely it would have been better to assume that all restrictions previously given are in force unless specifically cancelled?
E.g. Our TMC controllers give descent clearance with a requirement to reach F130 by the APP hand-off gate. That is to ensure that departures with a requirement to be above F140 by a point will not be in conflict as soon as they call APP. Normal hand-off approaching the gate, the APP controllers says "descent to 8000 ft". The F130 requirement should still be in force. Surely we don't want the APP controller to have to reiterate the F130 requirement every time to separate with DEP traffic he/she knows nothing about.
I reckon its a crock.

the last thing required is ambiguous phraseology leading to more transmissions
Not aimed at you but I also reckon there's a certain group out there in ATC who search for and can find ambiguity in almost everything that is said. The job has become a ridiculous game of semantics because of "bush lawyers" within the system.

[Pera]

In my neck of the woods a subsequent restriction cancels previous restrictions unless restated. The idea that a speed instruction is cancelled by a level or altitude assignment seems foreign to me... :) (pun intended).

[BGQ]

Descending into EGLL first controller "Descend to FL150 to be at FL150 by Baker"......

After changeover to the next controller and still above F150

"Descend FL80 turn right head ___

Is there a requirement to be at FL150 abeam baker?

We clarified the issue by asking but what do you think?

What do the controllers think?

[bekolblockage]

Pera, point taken, but I think the point was that when the aircraft was level
F150 it should reduce, however the aircraft never leveled.

[jackieofalltrades]

The other point pilots would do well to be aware of is that in busy environments as a controller it is important for us to have the aircraft vacate the levels to make room for other aircraft coming in behind. Hence the instruction which permits the aircraft to stay at speed til it reaches FL150.
I always remember the phrase, "you can't expect the aircraft to slow down and go down."

[5milesbaby]

autopilot_off: was it the same controller that cleared you below FL150 that had given the original instruction? If so then they should have reiterated the speed clearance (or just said "fly speed 220kts" as they gave you the descent through FL150 if you were nearly there).
However, if there was a frequency change then what did you report on first contact exactly? I had a situation once where this exact instruction was issued but then on contact with the new frequency it was reported as "descending FL150 by TIGER, 220kts". They were given FL80 before leveling and they didn't come back to 220kts and lost separation with the jet in front. The pilot was blamed for not passing on the EXACT clearance to the next controller and for making a false statement when they said they were doing 220kts to the next controller.

BGQ - all UK controllers know that a new clearance cancels the previous so if they still required the level restriction, they should have reiterated it. We don't like it but its a very black and white ruling.

[flyboy114]

In my neck of the woods (canada) I would read that as speed 220 kts@FL150. I would maintain 220 kts as I go to FL80. We're used to hearing "speed your discretion" or some such if the speed restriction gets cancelled. Other than that it's 220 kts till told otherwise. I agree it seems a bit ambiguous. We would, if passed on to another controller, be told "contact such and such with your speed". Not sure about EU airspace as I only fly in N.Am. right now, but here you would be expected to maintain your speed restriction regardless of FL clearance.

[autopilot_off]

Hi all, thanks a lot for the replies, very helpful.

It was indeed the same controller on the same frequency. I'll happily admit that I have very little idea of what goes on in the ATC side of things so I'm in no way having a go at the controller here.

What we took from his original clearance was that at FL150 he wanted us at 220kts so (possibly wrongly as it wasn't an actual clearance) we assumed the speed restriction applied to this flight level as opposed to the level flight aspect. In the past where this has happened there is normally a clearance of, "now cleared FL80, on passing FL150 speed 220kts" but on this occasion we didn't receive that. Again, busy airspace and the controller was having to work hard so it's understandable that a small omission like this may slip in.

5milesbaby: It's interesting the point you make about the pilot not passing you the exact clearance as I've flown with people who on initial contact will state "we've been given a speed of 220kts" whilst we're still at 280, and as someone said earlier, losing those 60kts can take time, especially if you've been distracted by the headlines and are coming in a bit hot! (That's a figure of speech by the way! There's no tray on my a/c and the control column gets in the way of reading the paper!) I'll make sure that we always make our speed and restrictions clearer in future.

[coracle]

Evening Autopilot Off.

A difficult one this not helped by a little ambiguity on the controllers side! I know one never should, but I assume (:E) that you were comming into LAM or BNN judging by your clearences. But what I try to practice and indeed teach is to say something like "ABC123 descend FL80 upon passing (abeam) SABER/SOPIT speed 220kts".

A difficult one from your end but if it happens again, as soon as you can get a word in then don't be afraid to ask what the controller wants.

[autopilot_off]

Thanks Coracle. The levels were made up because I couldn't remember the actuals but for your curiosity sakes we were inbound to GWC for KK.

[JayeRipley]

Agree with those that reiterate the speed reduction.

If I give a 'level by' or 'speed at' then give another level change before
the initial level is reached, I add 'previous level/speed restriction still applies'.

Similarly if an a/c calls on a 'when ready' to be level by and I reclear it to another level before it's commenced descent I give 'previous level restriction still applies'.

Most if not all my colleagues use the same or words to that effect.

Cheers

[5milesbaby]

autopilot_off - the standing agreement you would have been on is FL130 level GWC unless the TMA is holding high and ask for you to come in at a slightly higher level to help out. Freq 127.825 would have given you the descent to FL130 and then transferred you to 133.175 as you approached GWC. The SLP is GWC where, unless otherwise instructed, you should be 250kts anyway. I'm glad you came back to 220kts however the controller should have reiterated the speed when they gave you the second instruction.

Are you based in the south UK? A trip to Swanwick can certainly be a benefit ;)

[BGQ]

Interestingly the pilots in my company are being told by the training staff that they still have to comply with the original instruction. Can you give me a reference please.

In this case when asked the controller re-imposed the "descend by" restriction.

I don't like having to ask but I dislike the uncertainty more.

[jackieofalltrades]

I don't like having to ask but I dislike the uncertainty more.
That's exactly what this forum is for. I would rather you asked and got clarification.
It also highlights to us controllers that pilots might have a different interpretation of the instructions to what we expect.

BCQ> In the example you give the controller reiterated the descend by reporting point instruction and so this would still stand. However, by the book, if s/he hadn't then on issuing the descend FL80 command the "to be level FL150 at BAKER" part would no longer be required to comply with the instruction.
I know several colleagues that would still nevertheless be expecting you to be level FL150 at the originally given point, but as alluded earlier, it is best practice to reiterate the level restriction if it is still required.

[5milesbaby]

BGQ:

UK AIP ENR 1.1.3 - 2.2 Level Restrictions:
NATS | AIS - Home (http://www.nats-uk.ead-it.com/public/index.php%3Foption=com_content&task=blogcategory&id=4&Itemid=11.html) (click ENR 1.1 General Rules)
2.2 Level Restrictions
2.2.1 For all stages of flight, clearances to climb or descend cancel any previous restrictions or levels, unless they are reiterated as
part of the clearance.
UK MATS Part 1 (CAP493) Section 1 Chapter 4 Page 4:
http://www.caa.co.uk/docs/33/CAP493Part1.pdf
7 Amendments to Clearances
7.1 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 with the revised clearance.

[Pera]

I wondered when someone was going to get out the books.

[5milesbaby]

Pera, I'm with you on
the idea that a speed instruction is cancelled by a level or altitude assignment seems foreign to me...
however, in the OP query the instruction was "when level speed 220kts" and the aircraft didn't level so technically the instruction needs changing and reiterating. It is very unfortunate that there are so many law chiefs on preciseness and common sense doesn't take over but at the end of the day they are correct.

May be us controllers should avoid the loose phrase of "when level....." and introduce "speed 220kts at and below FL150" which I've used once or twice recently. Caution must be exercised though as the first time I said "Descend FL180, reduce to 250kts passing FL180" and the pilot then replied "but we're only descending FL180, so what do you want us to go down to now then?" :ugh: You cannot please everyone.

And the books reference was requested......... :8

[250 kts]

How about "at FL220 reduce speed to 250kts".

It doesn't matter whether they level off or not then.

[Plazbot]

I would restate it. Same with an altitude. No confusion then.

eg

speed 220K when level at A090.
Give further descent before A090 then say
Descend to A050, speed 220K passing A090

Only addition for level requirement is that if you then track the acft away from the point they had to cros a level at, specify a rate of descent ot at least something like continue present rate of desent and track direct to XXX.