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-   -   Expidite through which level? (https://www.pprune.org/atc-issues/170899-expidite-through-level.html)

unwiseowl 13th Apr 2005 22:14

Expidite through which level?
 
Question for radar controllers:

When you say, "expedite through FL150" do you mean the traffic's at FL150, or do you mean that FL150 is the level which will achieve separation?

(sorry if this has been asked before)

Lock n' Load 13th Apr 2005 22:41

When I use it, it means the level which will give me separation. Can't speak for everyone though.

Jerricho 13th Apr 2005 23:00

With Lock 'n Load with this one.

If asking for an expidite through an altitude/level, that will be the separated altitude from the traffic/airspace etc I am trying to separate you from.

DtyCln 13th Apr 2005 23:02

Agree with previous

If given "expedite climb until passing FL150" traffic is generally at FL140 or below.

Have been caught out before when I gave the expedite level as the same level as the confliction, and the aircraft, Airbus A321, reduced climb to 200fpm after the expedite and nearly caught me out.

Yes I know UK AIP states minumum climb in UK is 500fpm, most pilots don't notify ATC if unable however.

Cheers

Evil J 13th Apr 2005 23:25

Agree also, if I say expedite through 50 I mean just that! Once you are passed 50 you can go back to normal

BALIX 14th Apr 2005 08:00

Did exactly the same as DtyCln a number of years ago. The aircraft (an MD80) duly expedited to the level I'd specified and then basically stopped climbing when it traded climb rate for forward speed. Just about got away with it but the old sphincter was beginning to flutter.

It is fair to say I learned about ATCOing from that and always specify a level above the conflict. Sometimes several levels above the conflict...

EmergingCyclogenesis 14th Apr 2005 08:05

Here's one for the pilots then. If I asked you to expedite, what sort of climb rate could you expect to achieve in say a 737 or 757 at levels between FL 100 and FL300?

Capt Pit Bull 14th Apr 2005 08:30


If I asked you to expedite, what sort of climb rate could you expect to achieve in say a 737 or 757 at levels between FL 100 and FL300?
How long is a piece of string. Depends hugely on the flavour of 737, the loading, the speed we had at the start, and finally any wind gradients.

Anything between about 1,500 and 6-7000 fpm.

I fly 300,400 and 500.

Lightly loaded 300 at one extreme versus full -500 at the other. Add an unfavourable wind gradient and the latter may struggle even more.

CPB

EmergingCyclogenesis 14th Apr 2005 08:53

Pit Bull,

Thanks for that. It is a pertinent question although it might not seem so at the moment, I am interested in the upper figure of course.

Thanks for your reply

DirtyPierre 14th Apr 2005 10:38

I remember something about "expedite" in another thread.

The use of expedite is not great technique for a controller. Should really be giving a requirement to be at a level by something. Or at best something like, due traffic at F140 request best rate of climb through F150.

Many a controller come unstuck saying expedite, then it all goes bad.

Barry Cuda 14th Apr 2005 14:33

The use of expedite should never be your primary source of separation, but when it is used with discrete headings it can make the job an awful lot easier...

Talla Radar 14th Apr 2005 16:17

"Expedite through" is not CAP413 phraseology (in the UK). The correct instruction is "Expedite until passing". If ATCOs would stick to standard phraseology then they would avoid these sort of ambiguities.

I only use an expedite climb or descent for about 5000ft in "normal" operations. Some controllers use expedite for 10000+ feet, just so they don't have to vector traffic!

unwiseowl 14th Apr 2005 18:41

Very interesting, thanks. Do you guys know that most HGV a/c types have to trade R.O.C. against speed to expidite; there's not usually any more power available.

av8boy 14th Apr 2005 19:32


The use of expedite is not great technique for a controller.
Agreed. That's why I like to use "Gimme a good rate through..." or "climb like a banshee through..." or something else of that sort. That is what you meant, right?

:D

standard warning: Americans DO utilize irony from time to time...

Vampy 14th Apr 2005 20:43


Or at best something like, due traffic at F140 request best rate of climb through F150
But what does best rate rate mean? It's not inconceivable for pilots to hear that and then climb at the rate that is best for that aircraft in terms of fuel consumption etc etc. When training at the college I was taught this by someone who had come from TC who was caught out by saying 'best rate' to an A340 out of egll. Result? Climbed like a brick because that was the best rate in terms of economy of for the aircraft. Expedite means just that. Expedite. ie Get your ass in gear! Furthermore, using the term 'request' would be a big no-no for me. You requesting it doesn't mean the pilot has to comply. What happens if he says no? :p :ok:

Cartman's Twin 15th Apr 2005 09:46

Hello Folks.

Agree with the initial posters - when I say expedite through FLXXX, that's the 'safe' level. I'm not suggesting it was unsafe beforehand but certainly within TC that's the level you have to pass before we can point you in the direction you actaully want to fly in!

I most disagree most vehemently that it is 'poor' technique. Absolute rubbish. Within the London TMA if you didn't utilise the a/c abilities, and the pilot's of course, NOTHING would move. Occasional, and appropriate use of expedite helps ALL concerned. Bad technique? - Not in my considered.....

I would never put it as a request either. Puts variables into the instruction, if the pilot is unable to expediate - eg an A343 (I love you really guys.....) then firstly I wouldn't have asked at all, but I'd expect the pilot to say if they couldn't.

Referring to precise phraseology. Although the CAP phrase is 'expediate until passing', I'd say 90+% of controllers I work with say "expediate through". I find this causes far fewer misunderstandings with foreign pilots, and saves 2 seconds per pair of instruction. Multiply that by the 40 departures per hour and I've even got time for me crossword!!!!!


Safe day to you all - I'm going to lay in the sun!!

Ziggy 15th Apr 2005 10:59

I as a pilot see my colleagues utilise different ways af complying with the instruction to expidite. The one pilot increases his rate of climb with e.g. 1000 fpm thus only trading in speed at a slow rate. The next pilot selects MAX rate climb speed (not BEST rate) and his speeds drops quickly while increasing ROC with 3000fpm or more (and maybe 1000fpm was enough to do the job).
English is not my first language, but if I can trust my dictionary the word expedite means something like 'speed up' and not 'speed up as much as possible'. Correct me if I'm wrong here, but if I'm right the term 'expedite' is far from unambiguous.

I understand just saying expedite makes life a lot easier for controllers but wouldn't it be better practise to instruct to 'climb with minimum 2000fpm' or 'be level in 3 minutes'.

Greetings Z.

DirtyPierre 15th Apr 2005 11:35


Within the London TMA if you didn't utilise the a/c abilities, and the pilot's of course, NOTHING would move.
I'll have to take your word for that, never having been to LTCC, but I've met Paul Upton from there, so he can tell you what our centre looks like.

It is considered poor technique in Oz. Even by our busiest controllers in TMA. As for best rate meaning anything other than climb like a banshee (or a fart in a bath), well I don't know what pilot would think that best rate means for economy especially when you say "due traffic".

BTW, didn't we have this"expedite" argument in another thread?

Scott Voigt 15th Apr 2005 21:55

Dirty'

We use it as a tool here all the time. Its for when you want a pilot to not start to slow the climb at all and keep it going up so that you can get above someone that is either climbing behind them or even that is in front of them, and then go on to other trafffic. The reevaluate later to see how it is all coming out. If his expedite isn't anything different, then you cap the climb and go from there. It is more of a try to get the pilot to his/her requested altitude for traffic that you see either coming up or for something that isn't working the way that you would like, but you don't have to take immediate action with. Also no brain power to start figuring out rates of climb and time to closure etc...

regards

Scott

Bigmouth 16th Apr 2005 08:24

We're always expediting our climb. The whole point is to get to altitude as fast possible to take advantage of favorable winds, higher true airspeed and most of all lower fuelburn. Even with a max derate t.o., climb thrust will be back at max in the teens somewhere.
To expedite, trading speed for altitude is necessary (a zoom climb) and that only works for 2-5000' depending on initial speed. Once the speed is bled off, climb is going to be a lot less then it was initially, even without accelerating.


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