Turn ASAP 3

25.10.2004

Submission:

You posed a very interesting question. Normally, pilot would fly to the MAPt before executing any manoeuvres associated with the missed approach segment, even when the decision to abort the approach was made before reaching MDA/DA. Clearly, if the approach happens to be an ILS and the descent is aborted before reaching DA, the problem of identifying the MAPt arises. In a situation like this the only way to safeguard against early turns is to specify an identifiable fix (e.g. inner marker, or DME fix) as the earliest turn point. I think paragraph 21.5.3.2.5 of PANS-OPS Vol. II also implies this.

Obrad Puskarica

Senior Navigation Procedures Specialist - Airways Corporation of New Zealand

Answer or Commentary:

(I.W

That would sort out the earliest turning point but where would the latest turning point be?

By adding another fix to cover the latest turn will make the ILS missed approach text rather wordy.

Missed approach:-

Turn as soon as practicable on to heading 045°.

No turns prior to 1 DME ILS-DME and

turn before 1 DME ILS-DME passed the station.

Climb to ...............etc.



If you just specify a single DME position, i.e. 0 DME, as the turning fix then the procedure is no longer a "turn as soon as practicable" and you can't do parallel runway operations.)