Sorry, UK 75, but I think we have different ideas about what "in some detail" might mean.
Petrus quoted all there is in AFV Profile 51, 1972, which is as much detail as I ever recall seeing. The follow-up Profile 53, The FV432 Series 1973, doesn't mention the tank.
The Ian Allan Scorpion book by George Forte mentions vehicles based on the FV430 series weighing about 13.5 tons "which were judged too heavy" but then goes into a fair amount of detail on the lightweight high mobility series of vehicles under 5 tons.
Given that the FV432 weighed 28,000lb (12.5tons) empty, a 13-ton tank based on it would be difficult.
R.E. Smith, in "British Army Vehicles and Equipment" Ian Allan 1968 page 65 says
A second interesting light armoured vehicle, also the product of the Vickers organisation, is a light 13-ton ton tank, designed for air-portability and mountain operations. Again its manufacturers are very reluctant to provide information, and maintain that a complete reappraisal of the project is being prepared. According to details of its original construction, basically an FV432 standardized chassis has been employed, with the armament and turret of the Saladin armoured car.
[ie a 76mm medium velocity gun.
The Book "Vickers Tanks" by Foss and McKenzie (PSL, 1988) makes no mention of a Vickers 13-ton tank at that time.
What it does do is recall Vickers' part in developing the running gear for the FV300 light tank, an FVDE design from the Army Tank Dept Drawing Office, around 1950. The Vickers-built FV303 was the running gear prototype weighing 16tons 2cwt and in addition carrying 7tons of ballast instead of a turret. The FV300 would have had a 77mm gun, as on the Comet tank. This book also mentions another FVDE design, the 17.6ton FV400 light tank with 76mm armour and 77mm gun. Designated A46, "it should not be confused with the FV432 carrier series that appeared later."
Vickers followed up their involvement with FV300 by designing a 26ton medium cruiser tank with 77mm gun, followed by a 28ton version with Vigilante AT missiles in the turret in addition to the gun. This line of development then led to the 105mm gun 37ton Main Battle Mark 1 or Vijayanta for India. There are line drawings of the FV300, 26 and 28ton Vickers designs, but no 13 tonner, although I seem to recall seeing a photo of an Australian FV432 with Scorpion or Saladin turret, in a Jane's I think, for use in Vietnam. A British version was built with 30mm Rarden cannon in a Fox turret.
But the implication is that the "Vickers 13-tonner" was a genuine tank design using Abbot components. It remains elusive.
