Heathrow Airport MATS pt.2.
Section 1 (3.3)
3.3.2 VISUAL CHANGES OF LANDING RUNWAY
Controllers must be aware that any aircraft that is instructed to visually switch to an alternate runway, in the event of a missed approach, may expect to follow the instrument missed approach procedure for the original runway. Obviously this is not appropriate, therefore, if the aircraft is subsequently instructed to execute a missed approach, the procedure used must be included in the instruction.
This is not the standard international procedure, therefore controllers must place particular emphasis on ensuring that traffic making a visual approach will, if the need arises, execute the correct missed approach.
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