I think the main object was ....
I fort the main object (T11) was to see how high you topped out after you mishandled going up and it flicked - I fink above 42000 was routine.
Never had rear view mirrors in the Sea Vampire or Sea Venom.
We were still spinning the Sea Venom in late 1969. I always believed the reason the spinning clearance had not been withdrawn was because the Admiralty didn't realise we had any left in service.
LFH
........................................