Hi Speed insruction during descent!!

[tic]

Hi ATC, anywhere.
Given an instruction as a pilot to maintain " high speed". What exactly are you after? Sure, I can do it, up to a point, but in my airline, below 10000' agl it should be 250 kts IAS, max, but can be more, provided, I do not exceed 250 kts, below 5000' agl. At night, that may or may not be acceptable, but during the day, never above 250 kts, below 10000' agl. (bird strike hazard). ( yes I know some birds do fly at night).Suppose, it depends where you are operating. My question, is why cannot it be standardised, world wide? Surely it would make your job easier, and pilots as well, if we knew, we had to be at certain speeds at certain heights/altitudes, and it was mandatory for everyone. Correct me if I'm wrong, but most airliners, with perhaps a few exceptions, (heavy/light etc ),in descent and approach, fly at pretty much the same speeds, give or take.
Instead of having to ask this pilot to do that and another to do something different, perhaps it could be legislated. At least, you would know what to expect, and so would I.

On another topic, I have noticed that most UAE controllers, eventually clear you to, e.g.,"altitude" 2300 feet, as opposed to some who clear you, to, three hundred feet, which can mean 2300 feet or just 300 feet. ( Tiger Airlines crash, many years ago).
Personally, and I know it's correct RT to read back ALTITUDE, or FLIGHT LEVEL. Hardly ever happens, does it? ATC and Pilots!!!

It really is high time that things are standardised, so you as a controller, don't have to tell me to slow down or speed up, and I don't have to tell you, that I can't do it, and give you the extra work-load, that you probably don't need in the first place.

Tks for doing a wonderful job. Happy Christmas to all of you.

tic

[fixa24]

Standard speeds would be fantastic, if every aircraft was evenly spaced to start with. We change the speed to put you into a gap, or slow you to help create/make a gap bigger. I agree it would be a whole lot easier, but unfortunatly, if it were brought in, there'd be a whole lot more verctoring all over the sky. :hmm:

[REVOLUTION]

Tic, despite there being standard phraseology which ATC should adhere to inevitably a few non-standard phrases creep in.

In the London TMA we are frequently asked by aircraft (particularly inbound to Stansted) who are approaching the speed limit point if they can maintain high speed i.e. ignore the 250 kts speed limit. ATC may pre-empt this question by saying to the aircraft 'maintain high speed'. Also approaching the Lambourne hold when Heathrow are on 09 there is still a long way to go and if we know there is no delay we may say to the aircraft 'maintain high speed' again meaning disregard the speed limit point, which as it happens might be a better phrase to use on the R/T!

[P|_azbot]

In OZ, we have a great difference depending on what airport you go to. You may get a 340 to 40 instruction from a flow(back in the day) in a 727 or a 250 to 5 in an E120 but now it seems that we issue Max speed, cancel speed restriction below A100 which seems to me to be very open to interpretation. Take into account that a certain carrier out here does economy descents in 738s as slow as 250 IAS from transition, I can see that a specific speed at specific times would save any issues the crew may have.

p.s. I assume u fly a BA146 from your post.

The two, to arguement is a long and involved one. In oz once again, our AIP states that you say 'descend to two thousand'. Too many fools drop the to thinking they are being more concise. Unfortunately the book disagrees. My main concern is that country to country, the to is required and sometimes not.

[jangler909]

On another topic, I have noticed that most UAE controllers, eventually clear you to, e.g.,"altitude" 2300 feet, as opposed to some who clear you, to, three hundred feet, which can mean 2300 feet or just 300 feet. ( Tiger Airlines crash, many years ago).

Although ATC could be blamed for that one, I'd give the Tiger crew at least a nomination for Darwin Awards...

By the way, in my country we would say "two thousand three hundred feet" without saying "altitude".

[Tall-Lion]

that bird also flies on the readbacks of pilots who have bbeen cleared to descend to FL260....

xyz descending t(w)o six zero...
ATC : confirm flightlevel 260

xyz : affirm t(w)o six zero...:*

Get the picture ?

[jangler909]

Yes, except in your example flight level 60 would still make sense, unlike 400 ft for an IFR-flight anywhere in the world...

[sandstorm inferno]

On another topic, I have noticed that most UAE controllers, eventually clear you to, e.g.,"altitude" 2300 feet, as opposed to some who clear you, to, three hundred feet, which can mean 2300 feet or just 300 feet. ( Tiger Airlines crash, many years ago).

As per ICAO 9432 Manual of Radiotelephony paragraph 2.4.2 and ICAO PANS-ATM 12.3.1.2 it should have been:

"descend TO, TWO THOUSAND THREE HUNDRED feet"


Merry Xmas or should it be Merry Christmas :confused: :8

[CAP493]

Given an instruction as a pilot to maintain " high speed". What exactly are you after? Sure, I can do it, up to a point, but in my airline, below 10000' agl it should be 250 kts IAS, max,

Your airline's SOPs accord entirely with ICAO and many State requirements in regard to speeds below FL100.

Outside CAS i.e. what's currently categorised as Class A to E, ATC has in fact no authority to remove the FL100/250 knots speed limit. As others have already said, inside CAS however, this can be either approved (in response to a flight-deck request) or requested by ATC if it assists in maintaining the required radar separation when streaming arrivals.

The inherent pitfall in responding to an ATC request is that unfortunately, some (happily a minority) controllers do not seem to appreciate the relationship of aircraft height to speed, and so depending on the track mileage you have to the final approach fix, you could find yourself maintaining high speed as per ATC's request, only to then find you can't lose the necessary height for satisfactory glide-path capture.

The key consideration from the flight-deck perspective whenever asked by ATC to maintain "high speed" (and if none is specified, then it's entirely down to your interpretation) is to have full situational awareness in regard to track miles to the FAF and the likely routeing to get there - that way, you should be able to make an informed decision as to your choice of high speed.

Revolution's comment about Stansted (also applies to Luton) in the UK is absolutely correct - unfortunately, because of TMA airspace configuration (= it's crap and outdated) and the consequent vectoring limitations, the adoption of 'high speed' often results in a scramble to get down to the optimum level against distance-to-go i.e. a classic case of the flight-deck not having the aforementioned situational awareness.

If - as someone else says - you fly a 146, my worry is always the opposite end of the speed spectrum i.e. "minimum safe approach speed" - I've seen a BN Islander start catching a 146 on the ILS, when the latter had been instructed by an unsuspecting Tower controller to "slow to minimum safe"...

:ok:

[MaxReheat]

Might I venture to suggest that speed limits are abolished (hence no need for crews to clutter the airwaves by asking to maintain high speed) and imposed only as and when deemed necessary by ATC.

[Turn It Off]

Might I venture to suggest that speed limits are abolished

and seperation in Class G?

[CAP493]

Might I venture to suggest that speed limits are abolished (hence no need for crews to clutter the airwaves by asking to maintain high speed) and imposed only as and when deemed necessary by ATC.
Speed limits are not only used by ATC to maintain separation.

Many published procedures e.g. SIDs and SDRs, holding pattern entry procedures, holding patterns, etc., require to be flown at or below a particular speed in order to fly the procedure accurately and in some cases, to ensure separation from other routes and/or holding areas.

A speed 'free for all' would create losses of separation, aircraft on some routes inadvertently leaving controlled airspace, and in other areas, 'overshooting' the protected 'holding areas' associated with holding patterns.

The problem nowadays is that ATC-imposed speed control particularly in the initial and intermediate approach phases appears increasingly to be seen by the flight deck community as an impediment to operating the aircraft at maximum efficiency (e.g. fuel burn) and on time. However, these same flight crew presumably, wouldn't - at peak times - expect to be able to drive at 70 mph on for example, the M25, M27, M42, M62 or M8. And even if /when, Mode-S combined with ADS-B facilitates self-separation by the flight deck, a degree of self discipline will be necessary in order to ensure that a Le Mans style operation doesn't ensue!

However, by then I shall travel only by rail...

:hmm:

[one25six]

2 minute sequence.

one aircraft 30 sec late at the feeder fix.

next aircraft 30sec early at the feeder fix.

sequence is now 1 minute.

controller must fix - high speed is a good start.

thats why it happens.

if every company could fly standard descents and standard speed reduction schedule and cross feeder fixes at the right times the slow down / speed up scenario wouldnt happen

this is of course impossible.

the limitation is runways - one at a time seems to work best (2 at a time is bad and gets noticed) - what happens in the airspace is to make the runway thing work. ATC dont delay aircraft - other aircraft delay aircraft.

ATC are trying to achieve the same thing you are - except they work to make sure it isn't a free for all.

Standardisation? I agree - now tell me how we do it. It very quickly becomes a sovereignty thing and political - and then all common sense is abandoned.

Frankly - I am amazed it works as well as it does - and most of the time too!

[Heathrowinnit]

I seem to remember an incident recently when 2 similar aircraft were given "no ATC speed restriction" shortly after departure. About 3 minutes later they were sharing the same bit of sky! One sped up and the other didn't!

I think it's a UK thing for ATC to say descend/climb altitude ****feet. The word "to" doesn't appear immediately before any numbers, if at all.

Strikes me that this is common sense.

[one25six]

Climb to three thousand, would be climb Flight level to three zero anyway wouldn't it? (Especially where there is a low transition like UK)

[5milesbaby]

Climb to three thousand, would be climb Flight level to three zero anyway wouldn't it? (Especially where there is a low transition like UK)
I think it's a UK thing for ATC to say descend/climb altitude ****feet. The word "to" doesn't appear immediately before any numbers, if at all.
I always understood it to be "descend TO altitude ****ft" and "descend Flight Level ***" the latter not having any TO in it. So many people miss out the words Altitude and Flight Level.

Found the MATS Part 1 bit on it but it won't let me copy and paste, but its Appendix E page 9, paragraph 4.8 and says what I've written above.

[tic]

5MILES
You are right. To me anyway, it's a trigger to make sure either QNH is set, or QNE. It happens often, especially on older jets, where a distraction, can cause you to forget to set the correct alt setting. Saying TO ALTITUDE such and such feet, or saying climb/descend FLIGHT LEVEL such and such clears away any ambiguity. I was taught that and I think it is a good thing. Sadly, it doesn't happen often, but I believe it is correct RT.
I fly a 767 out of Abu Dhabi, and most if not all medium/heavy jets will have give or take more or less the same restrictions regarding speeds below 10000' agl, i.e. is 250 kts max, below 10000' and is a bird strike limitation, for aircraft wind-screens, and if this is the case, I don't wan't to be told to maintain " high speed" coz I certainly don't want an eagle or a vulture, or any big bird, making it very windy for me. My arguement, is, what is high speed? 400kts, 300kts, 50kts? Give me something clear and I can do it. If I can't I will say so. ( Company SOP's are there as well )Too much time is wasted on the radio, especially in busy airspace, saying relatively trivial things, when so much of it could be standardised. Surely for ATC, it would make seperation easier.

[jetrat]

sorry tic,
i always thought 250 below ten IS for standardisation of speed in terminal area. what do you you do with the big birds that soar above FL100?:confused:

[Hay Day May Day]

Normally below 10000FT/FL100 its Airspace Classification C where speed restriction is NOT applicable for IFR flights, unless restricted by the STAR. Pilots still request from ATC if "high speed" is approved. ATC use "high speed" approved if there is no specific restriction such as spacing. ATC should give pilot a specific speed if he wants you to fly fast etc. since "high speed" is not defined.

[Giles Wembley-Hogg]

Hay Day May Day

Why are you so desparate for "high speed" to be defined? As long as the controller is not using it to provide separation then there is no problem. Don't forget, controllers have a variety of tools available to control traffic so just because they have told you to keep high speed does not mean they are using speed control to separate, so your exact speed is of no importance. The flights behind you may be given vectors or may be descended on top of you. That way, even if you stopped in mid-air, separation would be assured.

tic

Your birds must be bigger and fly higher than ours. We have a 313kt limit below 8000' for our 767s. Including when we fly to your part of the World.

You can keep high speed. 250kts is your high speed. I don't see the problem - I really don't!

Worried I am missing something.

G W-H

[Spitoon]

I'm sorry to introduce a bit of reality into this debate but - in the UK at least - the airspace-related speed limit does not apply to many of the flights that are under discussion. Rule 23 of the Rules of the Air says23 (1) Subject to paragraph (3), an aircraft shall not fly below flight level 100 at a speed which according to its air speed indicator is more than 250 knots unless it is flying in accordance with the terms of a written permission of the Authority.
(3) Paragraph (1) shall not apply to:
(a) flight in Class A airspace;
(b) VFR flight or IFR flight in Class B airspace;
(c) IFR flight in Class C airspace;Rules is rules, as they say - and it helps to read them!

[Hay Day May Day]

Giles Wembley-Hogg

Why are you so desparate for "high speed" to be defined?


Desparate???
Where do you get that from in my post??? I'm just saying there's no definition for high speed. Nothing else

[Arkady]

There is no definition of "high speed", nor should there be. If a controller wants a particular speed he/she will specify it. The Controller is asking you to maintain high speed, ie keep going as you are and don't slow down or if you do have to slow down say so first. An instruction as vague as "maintain high speed" will not be safety critical - separation will not depend on it - but the ATCOs overall plan might!

[Giles Wembley-Hogg]

Hay Day May Day

You are quite right. I humbly offer my apologies. I am afraid I was reading this thread with a growing sense of disbelief and I misinterpreted your contribution.

As you rightly point out, there is no definition for "high speed", and neither is one required as Arkady rather neatly explains.

Sorry again HDMD.

G W-H

[av8boy]

In my experience, "high speed," "good rate," and all of their non-standard relatives are tools which are more carrot than stick--more of a "do what you can" request that keeps me out of the flight deck. As has been pointed out above, if I want a particular speed (my favorite..."two-ten to the marker, faster if you like...";) ), I'll say so. Almost without exception, when I use a phrase like "high speed" it's because something down the road will work a little better if you move along in a more brisk manner, but if you don't, no harm done. Although it might mean a turn or a speed assignment for you or someone else in a bit, but perhaps not.

Firm speed assignments are a different thing. In general I don't use firm speed assignments to make traffic flow more smoothly and everybody's life a little easier. I use firm speed assignments to keep metal exactly the right distance apart. Sometimes that's what's needed. Sometimes a speed a little greater than usual will be fine.

However, in no case should you be flying in any manner which is contrary to the regs, your SOP, etc, whether or not I tell you to (or you think I've told you to... for instance, I can tell you to "maintain maximum forward speed," but that speed better be below 250 knots below 10,000 feet). That's what I like about things like "high speed" or "good rate" (or a word that IS in tahe manual on this side of the pond, "expedite"). Like I said, it keeps me out of the flight deck. On the other hand, when I tell you to do something you can't legally do, you should be telling me "unable."

[Giles Wembley-Hogg]

... I should have added that in the USA "high speed" should be defined. It is worth remembering that over there:

"keep high speed" means "reduce speed 250kts"

"caution wake vortex" means "you are in the same wake vortex group as the preceeding traffic. No vortex separation is required"

"maintain" means "climb/descend"

"cleared to land" means "land after the preceeding 4 or 5 aircraft have landed successfully and vacated the runway"

I can't wait to hear what the definition of "turn left heading 180 degrees is"!

An increasingly bewildered

G W-H

[av8boy]

Pffffffft. Hardly bewildered. Simply lashing-out.

Oh, and just a pointer for the future... sarcasm will work much better in a case like this if you actually use the US phraseology in your example. You know, as though you've been here and heard it.

Also, you may want to take a moment to go back and look over my previous posts on various threads. You may be surprised to learn that I'm pretty service-oriented and harsh on my fellow controllers and that I have had this mindset for some 30-odd years in this line of work. Thankfully, it's going to take more than one jerk (or 100 jerks) to change that. Nice try though.

Unless you are incapable of expressing yourself in any manner EXCEPT passive-aggressive, I suggest you converse rather than pontificate.

That's ME lashing out.

Dave

[Giles Wembley-Hogg]

Dave

Really not meant as sarcasm! (We Brits don't JUST do sarcasm). I was suggesting that maybe it would be sensible to define high speed in your part of the World, since it is clearly not what some of us would at first think it is. Especially below 10000'.

Don't forget I really want to understand your clearances. Despite what you may think, I actually DO have to fly them. So you must forgive me when I come across examples of your phraseology which sound like they are instructions to do one thing (to a foreigner don't forget), when they actually mean something else.

After all. The last time Potomac APP told us to fly at "speed 290kts", since we were actually at 5000' did they not really mean "fly at 290kts after passing 10000'"?

I stand by to be corrected.

G W-H