NavList:

Eric van der Veen: You asked me about the Vulcan airborne sight reduction form. 

Eric
I last flew in the Vulcan on 25^th March 1980 43 years ago and more than half my age ago, so you will appreciate my memory might be slightly hazy. 

After that, I did use up some of my supply of unused forms on the ground, but I probably only needed to fill in about 1/3 of it, because most of the form was for taking care of the errors which only occur in the air such as acceleration error and Coriolis effect both of which increase greatly with speed. 

The form was meant to be used with the no longer published RAF 6 monthly issue of the UK version of the Air Almanac, AP3270 (?? 249), and the Bomber Command ‘Mears Slide’ for working out acceleration error.  If I recall correctly, some divisors in the final averaging aren’t explained and only become obvious if you sit down with a sheet of paper, draw a plumb bob on it, and start to work out the effect of along and across track accelerations on the bob. 

I also seem to remember that I worked out later that the divisors are specific to a cruising speed of 480kts, but I might be confusing that with something else.  Of course, we didn’t realise all this mathematical stuff at the time; we just did as we were told. 

I don’t have any personal copies of forms filled in for airborne shots.  Everything was handed in with the Nav-Plotter’s flight plan and ‘log on chart’ for post flight assessment and was then locked away.  I will try and look a form out and try and invent a fictitious sequence for you, but I already owe Adrian F a reply about drift meters and I’m a bit tied up with a couple of other projects I’ve got on the go:  a walk/talk on ‘Our Churchyard Trees and a dusting off of ‘The life and times of William Bligh’ for the local history group, plus the little 17’ ‘Doranne’ and the 27' river cruiser ‘Zephyr’ to keep shipshape. 

Re the chap with the Smith Mk2a s, I’d have to check if he’s still around and trading.  It was a couple of years before Covid.  I’ve not been much help to you so far, I’m afraid.  DaveP