Orange Tartan navigation system

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Beyond a description of what the system was to do, there seems to be very little information on this.

Does anyone have any links to information?
 
Orange Tartan was a research programme looking at Automatic Astro Navigation in daylight. Problem was to detect a star against daylight sky. Two approaches: a chopping system (as per-IR homing) and a frame-scanning (TV camera) system.
 
The following file in the national archives should be of interest: http://www.nationalarchives.gov.uk/...tails.asp?CATID=448763&CATLN=6&accessmethod=5


Seeing as the system is described as automatic would I be correct in assuming that its data was automatically fed into the aircraft's navigation system? Perhaps this was considered as a replacement for the manual astro-navigation periscopes used in the V-Bombers, with an automatic system feeding into the Mk10 autopilot combined with the G4B compass and Sperry G11 gyro unit?

I understand that the predecessor system was Blue Sapphire and that it was developed at the Telecommunications Research Establishment sometime up to 1953 with at least some involvement from Albert Maurel Uttley. I also know that the AN/AVN-1 (Kollsman KS-85) was trialled in the UK in about 1963, was integrated into the Nimod Mk1 and Kollsman set up a UK subsidiary in the early 60s.

I am still astonished that the Vulcan and Victor bombers was not fitted with a true inertial navigation system until the five Vulcan aircraft fitted with second-hand Carousel systems for the Black Buck missions, even the Victor tankers had apparently been fitted with either Carousel or Omega (radio rather than inertial) earlier than that....? It is especially surprising as the RAF went to the trouble of developing and accepting into service in 1961 an automatic landing system for the Vulcan so they clearly liked advanced avionics. Although some aircraft do seem to have been fitted with a heading reference system based on the inertial platform used in Blue Steel.

For anybody who is interested, Associated Electrical Industries Ltd got the contract to fully develop and manufacture fully transistorised conversion equipment to link the Vulcan's navigation system to Skybolt and to develop the other changes required to the V-bomber navigation system, I have yet to find out what those changes would have been though.

I also found a fascinating research paper whilst randomly googling the UK Skybolt/Vulcan integration effort and have attached it here. the interesting section for me as is as follows:

In 1956, the UK aircraft company A.V.Roe (“Avro”), based at Woodford, south of Manchester, was awarded the contract for developing an airborne astronavigation equipment to be capable of installation in British V-bombers (Valiant, Victor, Vulcan) - notably the Avro Vulcan, last of the line. This was to enable the aircaft to carry and launch the US air-launched ICBM (intercontinental ballistic missile) named Skybolt, then under development, but to be purchased for British use. I was recruited by Avro for the small research facility they were setting up for this secret purpose in Chertsey, Surrey, starting there in mid-1957.

The Skybolt guidance system was to be by inertial navigation, ‘astro-crutched’ by signals from within the carrying aircraft up to the moment of the missile’s release. Those signals were to be derived from the astronavigation system we were to design. The aircraft/weapon system was to be able to operate in ‘daylight’ at launch heights of 18,000-35,000 ft altitude, so sky brightness and brightness gradient were going to be important factors, in that the 2 stars needed had to be searched for and located faster than the drift rate of the aircraft’s inertial platform enlarged their patches of uncertainty on the sky, during the interval between precise-data input, just before takeoff from the ground, and attaining operating altitude. Thereafter, positional accuracy was to be maintained for a potentially long period of stand-off, pending any instruction to fire the missile. Spatially, the third dimension was the flight altitude, independently known.

The two principal design responsibilities of the Chertsey establishment were (a) a telescope small enough to be alt-azimuth mounted on a small existing gyro-stabilized inertial platform, with star-search, detection and any other related facilities, (b) a navigation computer and related mathematics for instructing the telescope where to look and search for the pair of navigation stars selected as suitable at that moment from a prescribed list.

The source is here, and the file is attached.
 

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That's interesting... I though Skybolt had its own star tracker, and that one of the reasons they only mounted it on the Vulcan is that on the other two the nose of the missile could not see the sky well enough for this to work, whereas on Vulcan it was carried relatively forward and thus had a good view.

However, if a separate tracker were being developed, then it is not clear why it would only be for Vulcan - perhaps that was an unrelated mission change. It also suggests that the tracker was not in the missile itself, which means there would have to be one for the B-52 as well.

And to add to the confusion, star trackers were normally used because the onboard INS was not accurate enough on its own to get the required CEP. INS accuracy depends on flight time, which means the star tracker becomes more and more useful as the range increases. So that *sort* of suggests you'd want the tracker on the missile, although the range isn't that great in the Skybolt's case.
 
Humphrey Wynn, RAF Nuclear Deterrent Forces states that the star-tracker location (whether it should be on the carrier aircraft or the missile) was a point of debate and that ultimately it was decided to mount it on the missile.
 
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There was some research ongoing for Orange Tarten on how to measure the position of Polaris in day and night conditions. A report available at the National Archives (AVIA 65-657 dating 1956) gives details of using some contemporary CRT image tubes for that purpose and the result was, that with the contemporary equipment, namely the tube VCRX360 is not sufficient for that purpose, esp. in day conditions. Here pictures of the setup given in the report - essentially a refractive telescope with a rack of readout electronics:

OrangeTartan0.jpg
OrangeTartan2.jpg

Funny - the in its day secret work was carried out in the Reserach Laboratories of Electric & Musical Industries Ltd.
 
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There was some research ongoing for Orange Tarten ... Funny - the in its day secret work was carried out in the Reserach Laboratories of Electric & Musical Industries Ltd.
Sorry for my confusion, but is the work in the image at EMI? If so, what is its relationship to the work at AV Roe?

Whenever I hear "Electrical and Musical Industries" I cannot help hearing Johnny Rotten's pitch-perfect sneering delivery... "Who? EMI!"
 
Hm, I do not have got any details on "the work at AV Roe", but here is the header of the report the pictures are taken from:

1703061585795.png
1703061594306.png

Essentially the work is an investigation whether and under which conditions the dynamic range and the noise of the VCRX360 picture are sufficient to track Polaris. So for that investigation someone with experience in the emerging CRT based video recording probably was absolutely the right choice ;-) The report initially was classified until finally opened in 1988.
 
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