Referee!!!!!!!
Thumb joint = (8mins @ 150 mph) 20miles. Your figures.
Thumb joint =1.25 inches. Your figures.
Therefore 1.25 inches=20miles. Everybody agrees.
Five 0,25 inches = 1.25 inches.
0.25 inch = 4 miles
Four 0.25 inches = 16 miles.
1 inch = 16 miles. 16 miles/inch
I am assuming that you did not have aviation maps at that time in India as there were no aviation thingies to map. India was British and the first maps in the UK were 6 inches to the mile and at your time 4 inches/mile was de rigeur. India was too big for general large scale mapping so outside the main cities they would have been fairly snall scale showing only the three ‘Rs’, roads, railways and rivers plus cities and notable towns. Mountains would have been shown by hashers, a series of dashes indicating a wall of rock of some indeterminate height. We used this type of map in North Borneo in 1966 nicely decorated with white patches marked ‘relief data incomplete’. The people that knocked up these maps in India would have probably been guided by experience in England and could well have gone for a multiple of the 4 inches/mile format; ie 16 miles/inch.
I claim First Prize.
I was in ATC at Leeming '67 - '72 (last posting before retirement).
So YOU belonged to the bunch that brought out those rules about Avgas and Avtur lines at Leeming just because somebody tried to fill up a Basset with jet fuel.
I was leading a pair of Pumas from Odiham to Otterburn to lift some guns around for the Royal Artillery and we went into Leeming to refuel. On board I had an Air Vice Marshall who had just taken over 38 Group and wanted to see how his troops performed.
On arrival the Air Trafficess was of the belief that all helicopters were petrol driven so we were guided and then shut down in the Avgas line. It was a chilly day so I had lent the AVM my combat flying jacket whilst we refuelled. They had sent an Avgas bowser so we shooed it away and told them to bring an Avtur example. This was refused because Avtur bowsers were prohibited from crossing the Avgas line. There was a bit of a confrontation about this and eventually a Sqn Ldr groundocrat told us that if we wanted them refuelled we would have to PUSH (5.5 tonnes) our aircraft to the Avtur line.
At this point my Air Vice Marshall took my jacket off.
We didn’t seem to have any trouble after that. What was annoying was that the bowser driver told us he had refuelled a DH125 parked next to us, also in the Avgas line, less than an hour previously.
After that that AIP had a note for Leeming that if an inbound aircraft had a senior officer of Air Rank on board than the tower was to be informed on first contact. This unique instruction was still around at the turn of the century.