Originally Posted by
chevvron
Back in the '60s, possibly later, Cranfield were always A/G at weekends; nobody in the tower, just make all calls as standard.
Indeed. It was common practice if ATC were unavailable, right up to the mid 2000s for out of hours ops to take place on a Air to Air basis subject to the relatively straightforward terms of an out of hour permit.
The change of approach appears strongly correlated with changes in management.