M1, S1, C12 - Speed Control Flashcards
Controllers may request pilots to increase/decrease speed in order to facilitate a safe and orderly flow of traffic.
Speed adjustments should be limited to…
…those necessary to establish and/or maintain a desired separation/deconfliction minima or spacing and should not be outside the speed ranges laid down in MATS Part 2.
Pilots shall be advised when a speed control restriction is no longer required.
Speed control should not be applied in the following circumstances:
(1) In holding patterns, other than where published on approach charts;
(2) In areas of thunderstorms or known turbulence.
At levels at or above FL280, speed adjustments for aircraft in the cruise should be expressed in multiples of…
…0.01 Mach
At levels below FL280, speed adjustments should be expressed in multiples of…
…10 kt based on indicated airspeed (IAS).
The application of speed control should be appropriate for…
…the phase of flight, as its application over a long period of time may affect aircraft fuel reserves, and can affect the aircrew’s planned operating profile.
Instructions involving frequent changes of speed should be avoided.
Pilots will adhere to the speed (IAS or Mach Number) approved or assigned by ATC and will request ATC approval before making any changes thereto.
Pilots of aircraft unable to maintain the approved or assigned speed (e.g. for aircraft performance reasons) will inform ATC as soon as possible.
In such circumstances controllers shall…
…apply an alternative method to establish or maintain the desired separation/ deconfliction minima or spacing between the aircraft concerned.
For aircraft at or above FL280 that have been cleared to descend to levels below FL280, speed adjustments may be based on…
…IAS.
However, controllers should be aware that pilots might not be able to immediately change to IAS, as the timing of this change is dependent on variable aircraft system factors.
Instructions for an aircraft to simultaneously…
…maintain a high rate of descent and reduce its speed should be avoided.
Where possible, aircraft should be allowed to descend at their own preferred speed.
Most operators have indicated that their preferred economical descent profile is in the speed range 250 – 280 knots, with 270 knots being seen as a good compromise where streaming is necessary
Aircraft should not be instructed to operate at a high speed by one controller and, on transfer to the next sector, be instructed to reduce speed significantly.
Aircraft should be transferred from en route to Approach control in the speed range of…
…250 kt - 300 kt IAS; speeds outside this band should be co-ordinated with the receiving sector.
Allocated speeds should take into account speed limit points and target levels where published
Controllers should endeavour to permit aircraft to operate in a clean configuration for as long as circumstances permit.
Arriving aircraft below FL150 should not be allocated a speed of less than…
…210 kt (200 kt for propeller aircraft) unless within 20 track miles of the runway threshold, at which point the speed may be reduced to between 150 and 180 kt.
In exceptional circumstances a pilot may be asked to reduce to ‘minimum approach speed’.
Speed control should not be applied to aircraft after passing…
…a point 4 NM from the threshold on final approach.
Commercial aircraft operations require that an approach is flown as a ‘Stabilised Approach’, in which an aircraft should be in its landing configuration and at its final approach speed by…
…at least 1000 feet above the threshold elevation.
If agreed by the aircraft operator this may be lowered to 500 feet; however, this is not to be considered as normal operations.
The higher the speed applied on final approach, the greater the chance of an approach becoming unstable and a missed approach being initiated.
For departing aircraft the minimum speeds allocated should be:
(1) Jets 230 kt;
(2) Non-jets 150 kt;
(3) Helicopters 60 kt.
