SID Climb, a question

[SixDelta]

A Question that came up on a briefing we had today:

Cleared for a SID with an additional clearance to a level above the final level given on the SID chart. i.e. SID clearance limit is FL60, you're cleared for the SID but instructed to climb to FL100. Do we still have to adhere to the "stepped climb" limits (if applicable) in the SID or does the clearance allow us to climb straight to FL100 following the SID "ground track"?

To clarify, it came up on a discussion about the use of VNAV for SID climbs.

Thanks

[Turn It Off]

I am sure people will come up with another answer to mine on this one!!

If I (the I is important there i expect) issued a climb to FL100 whilst you were on SID (or a descent on a star for that matter) I would not expect you to follow the vertical profile in the SID unless i specifically stated that.

Probably however quite a grey area.

[Slaphead]

SixDelta,

See FODCOM 1/2006 and the associated Safety Leaflet which gives the definitive answer, available at;

http://www.levelbust.com/downloads.htm

[SixDelta]

Slaphead

It doesn't really give a definitive answer to my question. Obviously if you're not sure you're going to check. it does not say whether a clearance above the "final SID level" absolves you from the stepped climb responsibilities.

My personal belief is that you should adhere to the stepped climb, the "higher" clearance only counting on completion of the SID i.e no need to level at 6000', climb to FL100. Probably the safest way to do it.

[Slaphead]

Unless I am missing something I thought that the following clarified the question although admittedly I hadn't read the original question in the context of receiving the amended clearance on the ground..


'When an amendment is made to a clearance, the new clearance must be given in full to the pilot by the air traffic controller, and this new clearance automatically cancels any previous clearance.Thus, when an air traffic controller issues a clearance, which amends the route or vertical profile of an aircraft on a SID, e.g. 'climb FL 120', this automatically cancels the vertical profile of the SID. If the profile contains a restriction which provides vertical separation from conflicting traffic on another SID, air traffic controllers must reiterate the restriction, e.g. 'climb FL120, cross XYZ 5000 feet or above'. Similarly, when air traffic controllers issue instructions which amend the SID route, they are to confirm the level profile to be followed e.g. 'fly heading 095, climb FL 80' or 'route direct to ABC, stop climb at altitude 5000 feet'.

[SM4 Pirate]

In Oz if we no longer want you on the SID profile we will say "cancel SID, climb to FL120" when cancelling SID we would also give route or heading instructions too, just to ensure there is no cockpit confusion etc.

Otherwise a clearance to a higher level is just that a clearance to a higher level, nothing to do with your route (SID or STAR) and/or the routes limitations/restrictions/requirements.

[Tarq57]

And in NZ, prior to takeoff, we will say "Track via the SID, climb to....."
(The phrase used to be "Cancel maintain xxx thousand, track via the SID, climb to ...."

[Pierre Argh]

IMHO depends upon the wording of the clearance... "SID climb F100..." unrestricted; whereas "On completion of the SID, climb F100..." you're restricted. Clearances have to be carefully worded, as this and many other threads here have shown

[SixDelta]

Thanks for your input guys, we're talking about an unamended initial clearance here.

The original question still remains unanswered: if, prior to getting airborne, you are given an "XYZ 1 Y" departure with a clearance to a higher level than the SID (as published) allows do you still have to adhere to any "stepped climb" restrictions?

So far we've had different answers from current Controllers at a major UK airport and the College of Air Traffic Control at Hurn.

Seems to be a bit of a disconnect here, leading to confusion in both ATC and the flightdeck and quite possibly Level Busts.

[Willard W. Willard]

If the clearance for the higher level/altitude is given together with the dep-route ,any restriction within the dep-route is still valid.
Only the "climb to" level/altitude has been amended.
However I would always confirm the restriction with the clearance.
Other countries might have different regulations.

WWW

[SixDelta]

WWW thanks

Just to clarify i'd like to know the UK answer, unless of course it's a standard ICAO thing :)

[Over+Out]

I'm a TC Controller .
If you are on a SID, and I say nothing about levels/altitudes,I expect you to follow the SID profile.
If you are departing, say, LL on a DVR SID and I say ' Sqwauk ident,No ATC speed restriction,climb altitude 6000' '( which in this case also happens to be the final SID alt). I would expect you to cancel any SID level restrictions and climb directly to 6000'.
The same would apply if I climbed you to any FL, I would expect you to climb directly to that FL with no stop offs.

[Slaphead]

SixDelta

Just to satisfy my curiosity which UK airport are we talking about here?

Slaphead

[SixDelta]

Over+Out,

You miss the point, we're talking about the INITIAL CLEARANCE given on taxi prior to departure, not about ammendments made after take-off.

So, once again, if cleared on the Initial Clearance (from GND or Delivery) to a level higher than the SID allows, are we allowed to go straight to that higher level, ignoring the "step climb fixes" whilst following the SID lateral profile?

Slaphead, rather not say at the moment :)

[Over+Out]

SixDelta.
TC Contollers do not give Airfield Controllers levels above the SID.
We often ask Tower Controllers to stop a SID at an intermediate altitude, eg not above 4000'
In which case I would still expect you to follow the SID profile until the level specified and maintain this level until you receive further climb.

[SixDelta]

Over + Out, i've been cleared for a level higher than the SID on an initial clearance, maybe you don't but some places clearly do.

So far from conversations with various controllers there does not appear to be a clear understanding of what is expected. I've had "yes you should adhere to all stepped climb limits only climbing to the higher level on completion of the SID" and "no, you can climb straight to the higher level while following the lateral path of the SID"

I'd like to know which is correct but i'm not sure anyone really knows!

In the meantime if it happens again, i'll ask the question prior to getting airborne.

[Pierre Argh]

Six Delta... I'm sure you realise the climb clearance above the SID has probably been given for expedition... avoids the need to issue two clearances, or maybe at the time there may no need for the standard restriction?

Sorry you feel there is confusion... indeed it seems there is, but as several have said if ever in doubt about your clearance question it... ATCOs have to think carefully about the clearances they give, but a question often highlights an unthought-of abiguity... CRM I think you call it?

[SixDelta]

Pierre

I believe i just said that was what i would continue to do.

Seems strange that the College would teach one thing while operational controllers would expect exactly the opposite. Someone needs to get their ducks in a row.

[ukatco_535]

Six Delta
If you are flying from one of the London TMA Airports and the radar controller tells you to climb to a level above your SID level then you can climb to that level unrestricted. In fact, I will rephrase that, not 'you can' but 'you should'.

That is how we operate in the London TMA. I would suspect that other TMAs in the UK are the same.

For example we will sometimes will give a/c that are on a restricted SID a higher level in an effort to beat Heathrow traffic because we know that the Heathrow traffic will be stuck down at SID levels due to stacks etc.

It would be potentially dangerous if that a/c was then to follow the SID climb profile before dawdling up to the higher level.


The SIDS in the TMA are designed around Heathrow and are done to provide initial separation only - if we can give you a higher level we will do - our aim is to get you up and off our frequency as quickly as is safely possible. No controller in the TMA should give you what is effectively a conditional climb to a higher level (the condition being follow the SID levels)

Unless you are given a condition to any clearance, then you should fly your a/c in accordance with the clearance as soon as you are in the correct configuration to do it.

[SixDelta]

Thanks guys.

Looks like we're going to have to chase it through SRG to get a definitive answer.

Cheers

[2miles600feet]

In that case, expect the 'definitive' answer some time post 2015.

[Pierre Argh]

SixDelta, sorry if I ruffled your feathers. I don't think you'll find a definitive answer, even SRG will give you an interpretation (although it may be true thay have the power to enforce their will) but that will only apply to UK Civil airports (i.e. the minority of airfields)

Listen to the clearance. Like I've said before ATCOs have to think carefully about the wording to avoid ambiguity (and therefore most of the time will get it right)... pilots have to listen carefully to the clearance and fly it as given. If in doubt ask... approaching feather ruffling stage once again!!!!

[Pierre Argh]

Thinking on about this.... if the Controller doesn't want you to fly the SID profile before climbing to the higher cleared level, why would he used the phrase "SID" in the first place... surely a non-standard release clearance would be more appropriate?

[Slaphead]

Pierre Argh

Using the SID would ensure that any noise restrictions would be complied with, if you go down the route of a non-standard clearance you run the risk of making the clearance very wordy or open to misinterpretation. Funnily enough he/she managed to do that anyway...

[jonny B good]

SIX DELTA.....

CHECK YOUR PM's

[Pierre Argh]

Slaphead... As a Controller I understand SID's, why they are used etc... and that to give a non-standard clearance could be wordy.

If you re-read my previous posts you will see I was simply offering Six-Delta an interpretation of the instruction he had been given that started this thread in the first place?