"Dave Butler" wrote in message
...

(a) When vacating any previously assigned altitude or flight level for a
newly
assigned altitude or flight level.

I agree this is an interesting question and raises an area of some
ambiguity.

However, my interpretation in all the cases discussed in this thread is that
an intermediate altitude is not an assigned altitude and an approach
clearance certainly is not an assigned altitude.

In other words, I interpret the above AIM section to require the pilot to
provide a readbak of any altitude change. That readback might be "N102KY
out of 5000 for 3000" or it might be "N102KY out of 5000 for 3000 pilot
discretion" or it might be "N102KY will cruise 3000" -- any of these in my
opinion satisfy the AIM requirement.

The AIM doesn't say (for example) "...unless the altitude assignment is
superceded by a clearance for a visual approach".

Take the somewhat more extreme example of a DME step-down approach. Surely
you will agree that there is no need to report to ATC each time you proceed
to a new step-down altitude. Why not? Beause these step-down altitudes
were not "assigned" by ATC; you were instead "cleared for the approach"
which is approval to descend as published on the approach plate without any
further discussion with ATC. "Cleared for the visual" is just another
extension of this underlying theme -- you may descend at will upon being
"Cleared for the visual" as long as you do not violate another FAA rule in
the process such as minimum altitude requirements.



--
Richard Kaplan, CFII

www.flyimc.com