Having just come on board this thread it takes me back to 1963 with Valiants on 543 Sqn. Well, we were a
PR/ Recce outfit, and I remember when we started a form of MRR calling it Operation AGAT. They were long boring sorties, at least for the pilots, A different matter for the multi talented guys in the back. We operated so far north that the G4B compass was useless so it was all done on gyro with a 15 minute sequence of sun shots. If the sun was below the horizon they had a device called a twilight computer. This gathered all the light it could find and calculated where the sun would be if you could see it! It was made all the more difficult for them because the search pattern looked like the battlements of a castle. No airways of even civil traffic so we used to "cruise climb" starting at about 28K and ending up at around 50+K after 7plus hours. I think this was where MRR started.