We were listen only on the Nimrod frequency and they were only broadcasting positions so it was a method of launching silently without alerting the enemy!
We broadcast on a different frequency on which the Nimrod was listen only. The idea was to give us a better chance of survival if it was for real. We did the practice in the south west approaches, probably a Spanish fishing fleet.
As for the race, well I did a practice approach at St Mary's in the Scilly Isles and we were still in the bar before the Nimrod Landed