I'm fairly certain they were taken on the flypast for RN closure at Sembawang or possibly the practice Sep/Oct 71.
It is possible it could have been the FEAF disbandment parade - a multi feature flypast of RNZAF frightener with Whirlwinds either side, ourselves with you, Sqn of Lightnings, Sqn of Mirages (RAAF) and a few other odds and sods. Unfortunately the slides are all mixed up and undated.. Here's us looking down:
And one looking up: