Re: Reading "Approved" back
 

I think you're missing the point, TATC, that a clearance differs from permission or approval in that it is a contract between ATC and the aircraft. The ATC side of the bargain is that the relevant airspace is or will be clear, either of all traffic or of IFR traffic depending on the circumstances. The etymology of the word clearance as an everyday synonym for permission dates from the 1940s and ATC usage.

In the case of VFR in class D, the permission to enter a CTR is not logically a clearance as there is no promise of separation. That permission should be required to enter a class D CTR to create a known traffic environnment is not in dispute, nor, given the choice of UK law to require a clearance, that the RT phraseology should be "clearance".

Re: Reading "Approved" back
 

So aften another hour of looking through ICAO-docs I find in DOC 4444 (PANS-ATM) chapter 12.3.2.1: Area control services - issuance of clearance:

Phraseologies:
a) (name of unit) CLEARS (aircraft call sign);
b) (aircraft call sign) CLEARED TO;
c) RECLEARED (amended clearance details) [REST OF
CLEARANCE UNCHANGED];
d) RECLEARED (amended route portion) TO (significant point of
original route) [REST OF CLEARANCE UNCHANGED];
e) ENTER CONTROLLED AIRSPACE (or CONTROL ZONE)
[VIA (significant point or route)] AT (level) [AT (time)];
f) LEAVE CONTROLLED AIRSPACE (or CONTROL ZONE)
[VIA (significant point or route)] AT (level) (or CLIMBING,
or DESCENDING);


so the phrase "CLEARED TO ENTER CONTROL ZONE" or "CLEARED TO LEAVE CONTROLLED AIRSPACE" (example in CAP 413) is not in accordance with DOC4444.

Re: Reading "Approved" back
 

You're misinterpreting the structure of the table, JEP. Why would an ATC unit want to use the transmission "(name of unit) CLEARS (aircraft call sign)" in isolation? It would be meaningless. The phrases are to be concatenated, so (b) + (e) and (b) + (f) form exactly the phrases you quote.

Re: Reading "Approved" back
 

It's used by AFIS-units in our country. "XYZ control clears ABC123..."

Re: Reading "Approved" back
 

Yes, but (a) still needs something else to be meaningful. Agree (a) is used in the UK e.g. a departure clearance at Oxford might begin 'Brize Radar clears G-ABCD standard BOTLI departure...'

Tim