Platform Altitude

[Che Guevara]

If you are have been vectored for a 'straight in' non-precision approach, when can you descend from the MSA or MVA to the platform altitude?

Appreciate it if someone could give me the answer and the reference.

Thanks

[54.98N]

If you have been vectored, you are probably already lower than the MSA, but in terms of descending from your present altitude to the platform altitude to commence the approach, its when you are established on the approach.

You would normally be told by approach to descend with the procedure once you've called established.

[Che Guevara]

54.98N thank you for your reply.

I agree totally with what you say, however the question I was given included a 'suppose you are 20 miles out for example?' Any ideas on this one?

Thanks

Che

[alf5071h]

Take great care with any assumptions about when you can descend on an NPA. An early descent to MDA is not always going to be safe; see several of the incidents from the ICAO library - Celebrating TAWS ‘Saves’: But lessons still to be learnt. (www.icao.int/fsix/_Library%5CTAWS%20Saves%20plus%20add.pdf) Or alternatively the series of articles in FSF Aero Safety World, commencing here Threat Analysis. (www.flightsafety.org/asw/july06/asw_jul06_p40-42.pdf)

[BOAC]

That's when 'Dive and Drive' becomes 'Dive and Slide'

[Che Guevara]

Thanks alf507h, excellent article on TAWS etc.

Che