wrote in message
...

Experience and context has told us that "clearance on request" means the
tower
has requested it, but it hasn't come through yet. Having said that, in
plain
English it means they have the clearance whenever he would like to request
it.


An odd response to a request for a clearance. "Clearance on request" means
they don't have it at present, if they had it they wouldn't have to request
it.