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Old 27th Feb 2010, 12:19
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Back Seat Driver
 
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Quote Leadsled
PS1: Hint: The "racetrack" is a charting depiction of a holding pattern, not a track to fly.
It would be a good idea to actually read the rules for a holding patter, and consequently the actual shape of the obstacle protected area -- and the design rules for flying to remain inside....... What he was trying to say is that procedure design does not require drift correction to stay withing the protected area.
As some of you will be aware, we have had several recent incidents, where a pilot had tried to track the pretty little "racetrack" on their screen (not required) with some interesting results, when the bank angle limit was overridden to try and stay on the pink ( Sorry, "magenta") line in the turn.
I gather you are referring to the 5nm 'buffer' around the holding pattern, which also allows for a "an omnidirectional wind of 60 kt".
However the rules also say
FLIGHT PROCEDURES (DOC 8168) - GENERAL PRINCIPLES
Extracted from ICAO Document 8168, Volume I - Fifth Edition — Flight Procedures, PROCEDURES FOR AIR NAVIGATION SERVICES — AIRCRAFT OPERATIONS, herein known as PANS-OPS.
1 GENERAL INFORMATION
1.1 GENERAL
1.1.2 Procedures contained in PANS-OPS assume that all engines are operating.
NOTE: Development of contingency procedures is the responsibility of the operator.
1.1.3 All procedures depict tracks. Pilots should attempt to maintain the track by applying corrections to heading for known wind.
and
FLIGHT PROCEDURES (DOC 8168) - HOLDING PROCEDURES
1.3.3 Allowance for known wind
All procedures depict tracks. Pilots should attempt to maintain the track by making allowance for known wind by applying corrections both to heading and timing.
This should be done during entry and while flying in the holding pattern.

3.3.6 Wind effect
3.3.6.1 To achieve a stabilized approach, due allowance should be made in both heading and timing to compensate for the effects of wind so that the aircraft regains the inbound track as accurately and
expeditiously as possible. In making these corrections, full use should be made of the indications available from the aid and from estimated or known winds.
This is particularly important for slow aircraft in high wind conditions, when failure to compensate may render the procedure unflyable (i.e. the aircraft may pass the fix before establishing on the inbound track) and it could depart outside the protected area).
Therefore you should try to adjust heading to maintain the magenta line, and only then if unable to follow the line can you rely upon the inbuilt buffers in the procedure design.
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