Another unusual item
 

At first, this in the photographs looks like any aviation themed scale ruler. It has markings at 1:50,000 & 1:250,000. It has distances run at various speeds i.e. 420kt, 450kt & 480kts. There is also a conversion Metres to Feet scale, and a grid for accurate plotting on a 50k map.

However, one end is not at 90° to the main part of the ruler. It looks as if something has happened to the end, perhaps it was broken at some time, and was filed straight? But actually, this scale was manufactured as this shape.

So, what is it, and what is, or was, it for?

I realise there will be some Ppruners who will be familiar with it, so if they could hold of for a little while?


http://i238.photobucket.com/albums/f...pr9/Ruler1.jpg
http://i238.photobucket.com/albums/f...pr9/Ruler2.jpg

Quote
I realise there will be some Ppruners who will be familiar with it, so if they could hold of for a little while?

So are you saying we should only tell you what it is, if we know that we don't know?

Ruler for fast-jet flight-planning or for in-flight use by a Buccaneer or F4 Nav?

Edit: the PUP annotation at zero seconds and the TGT annotation make me wonder if it is a toss-bombing aid.

Allan,

Obviously some people will know instantly what the object is, and I ask them to hold off answering for a little while.

Those that do not know sometimes find it interesting to try and guess what the object is, and for what it is or was used.

FL

It reminds me of my FAC course at RAF Chivenor in the '60s.

Lovely course; best part was in the 2-seat Hunter being shown the pilot's POV during an attack; cab-rank to pull-up point about 20 miles at very low level ie contour flying, 420Kt, pull=up to 3000Ft AGL, 90 degree turn and dive to target, away at low level.

Then it was "what would you like to do on the way home?", or on one occasion "let's go to 40,000 feet and do a simulated flame-out and PFL from overhead, you just watch".

Yes, that little ruler had a purpose......

The piece of aluminium

http://i238.photobucket.com/albums/f...gforPprune.jpg

When Christine Finn's in-flight entertainment was accidentally tuned to cockpit radio on a transatlantic flight, the voice of air traffic control as they reached Irish airspace seemed to be welcoming her as well as the pilot.
As a creative archaeologist, she wanted to unravel the connections between those who fly the Atlantic and those who guide them safely over, especially when she discovered that datalink - effectively text messaging - is increasingly being used, so that voice communication is on the wane.
Listening to archive of transatlantic flights from the first by Alcock and Brown in 1919, Christine discovered that the west coast of Ireland looms large in the history. She visited Shannon airport in County Clare, scene of many departures and reunions and, in the 1950s and 60s - before the jet engine - a stop-over for most of the popular icons of the day as their planes re-fuelled after the 3000 mile flight; every US President since JFK has visited Shannon, and most stars from Marilyn Monroe to Fred Astaire.
And at the North Atlantic Communications Centre in nearby Ballygirreen, Christine met the faces behind the voices she heard coming out of the dark on her own Atlantic Crossing.


BBC Radio 4 - Archive on 4, Atlantic Crossing