Aahhh the noise, I had forgotten the noise.
Memory is faulty and silent at the same time...
Thanks for all the info. I did not realise that they were such a dog to fly. I also explains why there just aren't any around in Aus any more.
Talking about the rear view mirror, I told my parents that it was to look at the engine (after reading the posts) and they confessed that they had always thought it was to check for planes overtaking them. Old folks are strange...