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Captain_BH
19th Aug 2011, 09:49
hi guys

anybody knows if anywhere is stated the max rate of climb and desend enroute and during approach?

thanks

BrATCO
19th Aug 2011, 10:23
I don't know if anything is stated anywhere.
I usually expect 1000' per minute average (up or down), except for climbing A340 and long hauls shortly after their departure.

Experience shows that 3000' in descent is possible with no big fuss. I ask first if I need more.

I reckon it mostly depends on type of aircraft and the current flying conditions. Company policy, technical reasons, pilot's mood being factors we've got to deal with too... This can't be stated.

Crazy Voyager
19th Aug 2011, 10:48
The UK AIP states minimum 500fpm, I can dig up the refrence if you'd like.

Captain_BH
19th Aug 2011, 10:59
so it depends on the countrys AIP

thanks:ok:

Lord Spandex Masher
19th Aug 2011, 11:05
Can't find the reference or link for it but the maximum is 8,000fpm.

phantomlurker
19th Aug 2011, 16:57
Agree with LSM - 8000fpm, as I read it only this morning.

This excludes emergencies and TCAS RA and some military traffic.

pl

5milesbaby
19th Aug 2011, 18:10
In the UK is it a recommendation or rule that aircraft descend at 500 ft/min when in a holding stack?

ATC Watcher
19th Aug 2011, 19:41
I think some of you are mixing up minimum and maximum.
In my area :
There is a minimum expected (500ft/min ) but you can do less , and there is no maximum as any F16 or F18 pilot will tell you. (A military can fly GAT on an IFR Flight plan..)
Like with many things in life , you can get everything you want if you ask properly.
A DC8 with the reverses deployed can do 10.000ft/min descend no problem ,and if it suits you why not.
An empty B777 will happilly climb like an F16.

phantomlurker : for TCAS RAs it is the opposite my friend, gentle maneouvres, follow RAs with less than 1000ft/min as in 90% of the cases the max deviation TCAS will ask will be 400 ft....do more and you'll overshoot the protection .

BrATCO
20th Aug 2011, 02:51
I do agree with ATC Watcher on TCAS reaction vs protection. I guess the green bow must not often be in the 8000' region.
On the other hand, 8000' is a wee not enough for an emergency descent...
An empty B777 will happilly climb like an F16.

I saw once a Mirage F1 climb from runway to interception ("visual recognition", as should be said) at FL410 in less than 3 minutes (won't tell you the actual time). :eek:

And I've heard B738s bitch because I asked them for more than 100'/min in descent (due to constraints)... :rolleyes:
No ! They're not (all) RYR : Airbuses bitch sometimes too.

To come back to the original question, I reckon we (controllers) think more often in terms of minimum rates, rather than maximum. Even though we know there is a maximum, better not ask for it and remain in reasonable numbers, if possible.

Lord Spandex Masher,
is 8000' the max we may legally ask for, or the max a pilot can technically do (eg for passengers' comfort) ?

Guy D'ageradar
20th Aug 2011, 07:24
Can't find the reference or link for it but the maximum is 8,000fpm.

Don't remember ever seeing that.

What I DO remember is the CL60 that did 10500fpm descent when asked to expedite due traffic - then damn near managed to do it in the climb on the way out! :D We were all wondering whether the radar could show more than 10000fpm - it did!

Roffa
20th Aug 2011, 10:12
In the UK it's in ENR 1.1 of the AIP...

2 Climb and Descent

2.1 Vacating (Leaving) Levels

2.1.1 When pilots are instructed to report leaving a level, they should advise ATC that they have left an assigned level only when the aircraft's altimeter indicates that the aircraft has actually departed from that level and is maintaining a positive rate of climb or descent in accordance with published procedures.

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.

2.2.2 When a departing aircraft on a SID is cleared to climb to a level higher than the initially cleared level or the level(s) specified in
a SID, the aircraft shall climb directly to the cleared level, unless the SID vertical restrictions are reiterated as part of the clearance.

2.3 Maximum Rates of Climb and Descent

2.3.1 In order to ensure the credible interaction of Airborne Collision Avoidance Systems and ground based safety nets, other than aircraft in emergency and certain specific conditions for military aircraft (as detailed in Military AIP and JSP552), all aircraft when operating under normal circumstances, when inside Controlled Airspace within the London and Scottish FIRs/UIRs should not operate with a climb or descent rate exceeding 8000 ft per minute. Aircraft when first approaching a cleared flight level and/or when changing flight level in Controlled Airspace should ensure that the vertical closure speed is not excessive. It is considered that, with about 1500 ft to go to a cleared level, vertical speed should be reduced to a maximum of 1500 ft per minute and ideally to between 1000 ft per minute and 500 ft per minute. Pilots should ensure that the aeroplane neither undershoots nor overshoots the cleared level by more than 150 ft, manually overriding if necessary.

2.4 Minimum Rates of Climb and Descent

2.4.1 In order to ensure that controllers can accurately predict flight profiles to maintain standard vertical separation between aircraft, pilots of aircraft commencing a climb or descent in accordance with an ATC Clearance should inform the controller if they anticipate that their rate of climb or descent during the level change will be less than 500 ft per minute, or if at any time during such a climb or descent their vertical speed is, in fact, less than 500 ft per minute.

2.4.2 This requirement applies to both the en-route phase of flight and to terminal holding above Transition Altitude.

Note: This is not a prohibition on the use of rates of climb or descent of less than 500 ft per minute where necessary to comply with other operating requirements.

The wording all suggests it's more recommendation than rule.

During a CDA you can use whatever rate of descent is required to fly the CDA.

Lord Spandex Masher
20th Aug 2011, 10:42
Ok, not as clear cut as I suggested.

Guess I need to get out of Scottish and London airspace a bit more;)

aewaite17
20th Aug 2011, 20:06
I cannot speak for the 500ft, but I think that the 8000ft comes from two seperate issues:

Sometimes Mode C/S, particularly in dodgy areas, cannot interpret the readouts from A/c climing or descending that quickly (may also apply to the 500ft, as the arrow indication may not appear, thus making it difficult for safety / coordination / mil ops)... and potentially just removing the C/S completely.

The second reason I have been told may apply to W2D and fast EGNO climbers setting off TCAS that often that enough reports were filed to make some sort of response.... This is completely anecdotal but does make a lot of sense (I think?)

Captain_BH
21st Aug 2011, 07:00
I have been Through Out the Jepp Supp Manual, and it sounds the 500 Ft Which is not Mandatory as well applies in UK and SWISS only...

D-OCHO
21st Aug 2011, 08:02
Minimum rate of climb and descent is 500 ft/min.
It is a TCAS limitation.
Anything below the 500 ft/min your climb or descent will not be shown as an arrow on another TCAS. You will only see the vertical seperation reduce or increase.

Captain_BH
21st Aug 2011, 14:27
you are abselutly write i have been through tcas details in fcom 1

thanks but again its not an AIP limitation accept in UK and SWISS

THanks:ok:

phantomlurker
21st Aug 2011, 21:26
Referring to the UK, 500fpm (climb or descent) is the notified minimum. However this doesn't preclude a rate that doesn't acchieve this minima, merely that the pilot is required to report to ATC if they are unable to maintain the minima. I think that aewaite17 may have it spot on.

ATC Watcher - I'm no pilot, so I wouldn't guess as to the actual input and required rate. I merely meant that the source I used (the same as Lord Spandex i'm guessing!) allows the pilot all the leeway required with any TCAS RA. I can't imagine an RA would require +8000fpm though! :eek:

pl

renard
23rd Aug 2011, 15:43
8000fpm!

Except for emergency descents, I can't really see myself doing that. Maybe if I was doing 300kts and got "PULL UP PULL UP" but otherwise you would have a very high pitch attitude and soon run out of puff.

TCAS RA's really should be a smooth manouvre with a deviation of about 300' resolving them- passengers should not be aware of them.

samotnik
24th Aug 2011, 07:19
8000fpm RA action is likely to cause another bogus RA with another a/c above.