speed control

[mxwbuaa]

in real air traffic control ,as a controller ,do you often use the method of speed control to adjust the progress of the aircraft? may you instrust an aircraft that in approach phase to increase its speed?
in FAA 71110.65 and ICAO doc 4444 ,there are similar statements :
keep speed adjustments to the minimum necessary to achive or maintain required or desired spacing. in 7110.65
speed adjustments should be limited to those necessary to establish and /or maintain a desired separation minimum or spacing.
I come from china, so not well in english, i want to know what does it mean by saying it . not to use the speed control method too frequently or just to limit the amout of speed adjustment to minimum?

[PMS]

hi mxwbuaa

Having operated in jurisdictions using both documents, they are trying to say to "use speed control to the minimum amount necessary".

If you can use only one or two speed control adjustments to achieve the spacing and flow required is much better for the aircraft and crew than using many speed control adjustments, which increases the workload in the cockpit and will have the aircraft well outside its profile.

Also one should avoid increase then decrease in speeds as well for same reason as above.

cheers

[mxwbuaa]

hi, in my opinion ,i think it means the amout of the spped adjustment should be limited to the minimu as necesary to achive the required separation. for example ,if speed reduction of 10 kt is enough for two successive aircraft to keep safe separation , not to instruct it to reduce speed by 20kt.

[chillie]

hi


If you have to provide specific spacing on final you need to control the speed of ALL aircraft. You need to reduce the aircraft’s speed in steps that make sense.

Here is a rough guide for beginner Approach Controllers.

Speed control is quite a complex topic. If you allow pilots to fly their own speeds, different operators, different pilots, different types etc, will all fly different speeds. This means that if you have to provide a specific spacing on final your job will be impossible.

Also, many times the speed the controller would like is very different from the speed the pilot would like. This means a compromise must be reached. Most aircraft should be able to comply with these speeds. Normal speeds used are 220, (200), 180, and 160 knots.

Here is a guide for max speeds you can use when speed control is needed.

Aircraft must be slowed down in steps, so lets start with what is require at the end.

Less than 4 NM from touch down: No speed restrictions.

Less than 8 NM from touch down: Max speed 160 knots.

Less than 12 NM from touch down: Max speed 180 knots.

Less than 15 NM from touch down: Max speed 220 knots. ( still clean speed for most aircraft)

Below FL100: Max speed 250 knots.



If you require aircraft to go slower, here is a guide. Much more subjective. Obviously pilots could go slower from much further out but it is not convenient nor economical.

Minimum approach speed: Not before 6 NM from touch down.

160 knots: Not before 12 NM from touch down.

180 knots: Not before 30 NM from touch down.

220 knots: As early as you like in the Approach environment.

[mxwbuaa]

hi,chillie, you 're excellent. thanks! I learn much from you.
return to the original question, "i want to know what does it mean by saying it . not to use the speed control method too frequently or just to limit the amout of speed adjustment to minimum? "
i must translate it to chinese accurately.
additionly , in trancon area ,do you really instruct an arrival aircraft to increase speed?

[chillie]

hi
"not to use the speed control method too frequently"


This means not to use it too often. In the Approach this does not make sense because as I said before; if you need to provide accurate spacing on final ALL aircraft need to have speed control.

"just to limit the amout of speed adjustment to minimum? "

This makes sense. There is not usually need to adjust the speed too often. Most pilots will be happy with first, minimum clean speed until a base or 12 NM, then reduce to 180 knots to 8 NM, then reduce to 160 knots to 5/4 NM.

[mxwbuaa]

hi， chillie, thanks
i think you did not grasp what i want to ask, the original question is:
in real air traffic control ,as a controller ,do you often use the method of speed control to adjust the progress of the aircraft? may you instrust an aircraft that in approach phase to increase its speed?
in FAA 71110.65 and ICAO doc 4444 ,there are similar statements :
keep speed adjustments to the minimum necessary to achive or maintain required or desired spacing. in 7110.65
speed adjustments should be limited to those necessary to establish and /or maintain a desired separation minimum or spacing.
I come from china, so not well in english, i want to know what does it mean by saying it . not to use the speed control method too frequently or just to limit the amout of speed adjustment to minimum?

[BaldEd]

mxwbuaa
I think that phaseology means to make only the minimum amount of speed reduction necessary to maintain the distance separation. i.e do not instruct a faster following aircraft to reduce speed by 50knots when only a 20knot reduction will be required to stop it from catching up to a leading aircraft. There is no limit on the number of speed control instructions that an approach controller may issue - it is a common form of control used to keep aircraft separated.

It is not normal to ask an aircraft in the approach phase to increase speed, though this is sometimes done early in the approach phase (say, 30+ nm from the airport) to expedite the arrival of the first aircraft in an approach sequence. Typically the instruction may be something like, "Maintain 250kts IAS to 20NM XYZ DME" where XYZ DME is at the arrival airport. As the aircraft approaches the final approach it will be progressively reducing speed in accordance with the company's SOP (Standard Operating Practice). Speeds quoted by chillie are what are typically used.

[On the beach]

Mach .86 into 340 knots. If you can't do that then you're always number 2. :E

Bring back the Tridents. 320 to 15. None of this namby-pamby stabilised approach nonsense. Bring back real pilots who knew how to really fly. :D

Merry Christmas.

[topdrop]

Give me the Westwind; 350 to 5 :ok::ok::ok:

[mxwbuaa]

hi, on the beach, do you agree with what BaldEd (http://www.pprune.org/members/38135-balded) says? as for me ,i agree with him.

[BOAC]

mxw - OTB is just winding you up for a Christmas joke. Don't get excited. He probably knows that some companies will demote Captains to the RHS for such behaviour. It would have been fun though while it lasted.:)

[mxwbuaa]

hi， thanks, merry christmas to you all!

[On the beach]

Hi mxwbuaa,

The bottom line with speed control is the faster the average approach speed, the more aircraft you can land per hour.

Slow speed approaches diminish your landing rate.

On the beach

[Flightwatch]

OBWAN

As one of the ca. 40 BA 1-11 pilots who fit the time frame - thank you! We always tried to accomplish what was asked of us by ATC who were unendingly helpful in return. My favorite was landing on 24 with a light a/c and sufficient headwind turning off on the fast turn off from 06 (link C?) straight on to stand 51/50. Less than 30 secs runway occupancy and 30s taxy time. Never had a pax complaint.

Much of the proficiency was gained operating the Berlin services within Germany. A straight in at HAJ when cleared to 1500' it was possible to maintain 330kts to 6 miles and stay within flap/speed brake/gear limits. SOPs were not so restrictive then. Also visual approaches were practiced frequently at THF to considerably shorten approach time, turning visually around the "Pope's Revenge" TV tower and pointing at the blue painted house on the Berlin wall, so long as you turned over it at 500' you were perfectly positioned on short finals.