Hi l have heard that according to ICAO ANNEX 10 VOL Il AMDT 82 the phrase 'GO AHEAD' is no longer in force. The thing is that l do not have this amendment. Can anyone help me confirm this information please? l will appreciate it.

l do not have the amendment either, but l know the phrase has been discontinued as an invitation to read back clearance after someone took it for permission to take off.

l think it was discontinued following the big accident where two 747s, one from KLM and the other from (i forget) collided on the runway.
the KLM pilot thought he was cleared to takeoff and smashed into another 747 exiting the same runway.

500 or so people perished

It is still standard phraseology in the US, according to the 2/14/08
Pilot/Controller Glossary

GO AHEAD- Proceed with ur message. Not to be used for any other purpose.

Also in the FAA is AVGO...
Section Four - Aviation Phraseology
Go ahead - State ur request

Amdt says..
. . .
CHAPTER 5. AERONAUTICAL MOBILE SERVICE —
VOICE COMMUNICATIONS
. . .
5.2 Radiotelephony procedures
. . .
5.2.1.5.8 The following words & phrases shall be used in radiotelephony communications as
appropriate & shall have the meaning ascribed hereunder:
. . .
GO AHEAD “Proceed with ur message.”
Note.— Not used whenever the possibility exists of misconstruing
“GO AHEAD” as an authorization for an aircraft to proceed. The
phrase “GO AHEAD” may be omitted and, in its place, a response
made by using the calling aeronautical station’s call sign followed by
the answering aeronautical station’s call sign.

see:
http://petrmatula.com/_staticfiles/annex10_new.pdf
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