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honey737
18th Nov 2002, 16:14
Hi everybody!

I would like to clear for myself one question. What is the minimum rate of climb or descent we should use? Are there any differences when we are en route or in TMA or Holding.
Can anybody reference me to the relevant document.

Thanks :confused:

Smokie
18th Nov 2002, 16:36
I believe its a minimum of 500ft /min ROD or ROC, if ATC ask you to expidite then they are looking for in excess of 2500ft/min.
I stand to be corrected though, anyone from ATC confirm or deny ?

NorthernSky
20th Nov 2002, 21:41
If you aren't achieving 500fpm, you must advise ATC.

'Expedite' means highest available rate of climb or descent. It has no numerical value in the UK.

Most ATCOs have a good appreciation of aircraft performance. Some don't. A long, long, time ago, I was on my way with a fore-runner of the present Mrs NorthernSky from Oxford to La Rochelle in a knackered old Seneca I (ex-OATS with the spare instrumentation to prove it!), which I had borrowed from a chum (my usual love-machine being on maintenance).

I was trying to coax the old girl up to FL110, and passing about 88, when ATC called: 'Golf thingy-whatnot, expedite until level'. I replied: 'I was just about to report that we're unable to maintain 500 feet per minute, Golf thingy-whatnot'. We ended up with a big turn and the traffic passed clear.

I guess said ATCO 'learnt about flying from that'.

eyeinthesky
21st Nov 2002, 08:44
It's specified in the AIP what the minimum rates of climb and descent are (500fpm as stated). Can't remember the exact reference but it's near the beginning of the Gen section.

Reference the use of 'Expedite':

The example NS gives is a brilliant illustration of how many ATCOs think 'Expedite' will solve all their separation problems. The difference between normal and expedited ROC in an A340-300 going to Tokyo might only be from 1200 FPM increased to 1500FPM (and they can only do it for a few thousand feet) and if you rely on that for separation you're in the poo. I prefer to ask what rate of climb they could manage until through a certain level and then specify that. Then you are operating to a known value rather than an unspecified 'Expedite'.

Of course you should not be basing separation PURELY upon ROC/ROD but should have a radar solution as well. The increasing of vertical movement can help in getting aircraft going where they want sooner.;)

fourthreethree
21st Nov 2002, 12:28
eyeinthesky has it spot on. Yup, 500fpm is the minimum without informing atc, but the word expedite means nothing. I don't believe it is mentioned in any AIP (feel free to correct me there) but even if it is, it opens up such a huge grey area that it cannot be used for separation purposes. As mentioned above, expedite for an A340 EDDF-KLAX means something totally different than it does for a B737-800 EDDL-EGLL.

Its simple for me, if you need a specific ROC/D in order to achieve separation, that ROC/D needs to be specified in the clearance, and read back by the pilot. Even then, depending on the situation, (opposite direction traffic for example) another solution must be kept on standby.

The use of "expedite" is, IMHO usually a result of the controller having missed a conflict when issuing a climb or descent clearance. I know, I've done it myself, and had my wrist slapped by my supervisor.

honey737
21st Nov 2002, 17:24
Many thanks to everybody who replied to my question.

The matter raised when I flew in London area and was descending with 500fpm. Then captain told me that this is wrong and I should use 1000fpm ( 500fpm when in hold). I referred him to the Jeppesen manual where it says in London area the minimum is 500fpm. He said that it is not correct and in ANO somewhere there is 1000fpm figure is mentioned. It looks like ANO and Jeppesen is in conflict.
From the ATC point of view what is the legal requirements? What about other areas? I didn't see in the Jeppesen anything mentioned about other countries.

I think the 500fpm helps to ATC to identify the aircraft as descending or climbing on the screen. And it is used in TCAS to display descending/climbing traffic. So that the reason to use 500fpm as the minimum.
:confused:

Vlad the Impaler
21st Nov 2002, 18:16
From a TMA point of view expedite is used more often not because the controller has missed a conflict when issueing the climb or descent but because we have short sector lengths in which to effect our plans and therefore work to far tighter tolerances than Area sectors. I agree that expedite must not be used to provide separation but it is nonetheless a useful tool under some circumstances to provide more of a comfort zone or make a difficult situation easier to solve. It is obvious that a ultra long haul A340 isn't going to be able to expedite, even to the most inexperienced controller, but a large proportion of TMA traffic is not travelling half way around the world and does have a bit extra to give on request. Not only can it solve our problems sometimes but some flexibility from crews can also result in more direct routeings. I appreciate that in a perfect world the crew would be able to set the most economical climb rate and toddle off on their merry way, unfortunately with the way the TMA has evolved this is not possible, if indeed it ever was, and to provide the best service to everybody we need to use these tools. As for traffic drifting down, 500ft per minute is the minimum but if the controller requires a greater rate then he need only ask or include a "Level by" in the clearance.

PPRuNe Radar
22nd Nov 2002, 10:34
Also a phrase not in the book is the use of the term 'Excavate'

Only applicable to JCB1, the biz jet owned by the tractor/digger manufacturers.

JCB1, excavate descent to FL120 .......

spekesoftly
22nd Nov 2002, 14:00
Certainly not 'in the book' ........ think you might be 'digging a hole for yourself' there .......... ;)

vector4fun
22nd Nov 2002, 15:44
From the U.S. AIM:

EXPEDITE- Used by ATC when prompt compliance is required to avoid the development of an imminent situation. Expedite climb/descent normally indicates to a pilot that the approximate best rate of climb/descent should be used without requiring an exceptional change in aircraft handling characteristics.

That's pretty much how it's used over here I think. I've used the term "Best rate" as well. I think, from talking to controllers in the U.S. at least, that enroute controllers make more use of defined restrictions/requests than terminal controllers. i.e. "Can you be level at FL330 in 20 miles?" I agree that using the term "expedite" without a Plan B or another form of separation immediately available is ill advised, but more often it's used to avoid a lengthy vector or altitude restriction.

Also in the U.S. Controller's handbook, 7110.65, is a table of climb and descent rates based on: average en route climb/descent profiles at median weight between maximum gross takeoff and landing weights.

Now, several of the reported figures seem like pure fantasy to me, but it does give a limited idea of normal expected performance. For example:

BOEING COMPANY (USA)


Model
Type Designator
Description
Performance Information

Number & Type Engines/Weight Class
Climb Rate (fpm)
Descent Rate (fpm)
SRS Cat.


707-100, VC-137707-100, VC-137
B701
4J/H
3,500
3,500
III


727-200
B722
3J/L
4,500
4,500
III

727 Stage 3 (-100 or -200)
B72Q
3J/L
4,500
4,500
III


737-200 (Surveiller, CT-43, VC-96)
B732
2J/L
3,000
3,000
III

B737 Stage 3
B73Q
2J/L
3,000
3,000
III

737-300
B733
2J/L
5,500
3,500
III

737-400
B734
2J/L
6,500
3,500
III

737-500
B735
2J/L
5,500
3,500
III

737-600
B736
2J/L
4,000
4,000
III

737-700
B737
2J/L
4,000
4,000
III

737-800
B738
2J/L
4,000
4,000
III

747-100
B741
4J/H
3,000
3,000
III

747-200
B742
4J/H
3,000
3,000
III

747-300
B743
4J/H
3,000
3,000
III

747-400
B744
4J/H
3,000
3,000
III

747SR
B74R
4J/H
3,000
3,000
III

747SP/SUD
B74S
4J/H
3,000
3,000
III

757-200
B752
2J/L
3,500
2,500
III

757-300
B753
2J/L
3,500
2,500
III

767-200
B762
2J/H
3,500
3,500
III

767-300
B763
2J/H
3,500
3,500
III


777-200
B772
2J/H
2,500
2,500
III

777-300
B773
2J/H
2,500
2,500
III

Now, before anybody laughs out loud, remember, this is an FAA publication.......

I get questioned by pilots about climbdescent rates, and the best answer I've heard came from an old friend.

"Climb or descend like it was YOUR idea, not ours..."

It happens fairly often in the last few years that Air Carriers and some Corporate are NOT descending at a rate that will allow a vector onto the final approach course in proper sequence. In other words, some folks are not getting down and slowed early enough for us to fit their aircraft into a gap on one of the finals, (though a few hard heads never quit trying). Consequently, these aircraft are going to the back of the line, or flying some pretty un-stabilized approaches. I think it would be to most pilot's benefit, (at least at the airports where I've worked) to hustle right on down to the assigned altitude and so be prepaired to slow and turn in should a gap develop. Instead, we're getting arrivals that seem to be planning a downwind, base, and 20 mile final from the start. (Believe it or not, tis not always so!)

I find that nothings civilian climbs better than a domestic 757, nor descends and slows as well as an old 727, though a few freight pilots flying Lears and Falcons certainly try to claim title from time to time.

And while we're discussing performance, a 757 doing 118 kts on final is a poor fit in front of a 737-800 or -900!
:rolleyes:

Smokie
22nd Nov 2002, 18:04
The 146 can stop on a Sixpence ! Execellent Airbrake !

And forgive my earlier definition of expidite, I now know that "a good rate "is in excess of 2500ft/min.:)

eastern wiseguy
22nd Nov 2002, 19:06
Smokie ..good job too with Victoria park looming on your horizon!!!!!!!!:eek: :eek: :eek: :D

NorthernSky
22nd Nov 2002, 21:24
honey737,

You were right. Captain was wrong. He/She needs to get used to that feeling. However, your later comments are wide of the mark,. 500fpm has its origins in procedural control, and the fact that some systems now use deltaCharlie for display purposes is irrelevant - their origins are in the same place...

Smokie,

'best rate' means... nothing. If I'm flying a long way, my 'best rate' will be ECON. No controller worth their salt should use the phrase. But it does call to mind...

Birdseed 123:
London, good afternoon, Birdseed 123 passing three thousand climbing six thousand Wobun departure, and we can give you a rate you won't believe'
LATCC:
'Birdseed 123 London, you're right, I won't, maintain six thousand on reaching.

Oh, and thanks fourthreethree for giving all the credit to the other bit of sky!!

fourthreethree
23rd Nov 2002, 01:05
oops, sorry northernsky, lets just say

The Skies have it!!

Lon More
23rd Nov 2002, 17:26
I think that the 500fpm descent has its origin in the hold - as soon as an aircraft reports leaving a level another can be cleared to that level - try that with TCAS:mad:
Slightly off thread: It would be "nice to know" if a flight is affected by the mach restriction, AD, placed on some 737s after deicing restricting them to not above 260IAS. To put it mildly , "The best laid plans of mice and men fu' aftimes gang aglae." when someone in a sequence suddenly reduces:eek: :eek:
also the almost unique (in the UAS) characteristic of the 145 of "changing up a gear" on reaching cruising level and increasing speed by about 50 knots.
433 Fingers rapped, not on our team; it was meant to be a thick ear, but you put your hand up;)

"Climb as if your life depended on it, because it does." = oops, I f****d up!

mainecoon
23rd Nov 2002, 23:25
northern sky

yes your point on best rate has been made clear at manchester uk with an incident pointed out when the crew let the computer do the optimum as regards fuel etc
we now have to use expidite or maximum rate

thanxs for that