Village Inn (codename)
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Village Inn was the codename for the British Airborne GunLaying in Turrets (AGLT) radar-aimed gun turret fitted to some Lancaster bombers in 1944.
The AGLT system was devised to allow a target to be tracked and fired-on in total darkness, the target's range being accurately computed as well as allowing for lead and bullet drop.
The system was devised by a team led by Dr P.I. Dee and designed under the aegis of Chief Designer Dr Alan Hodgkin, after receiving a request from the Air Ministry for such a system in early 1943. It worked on a wavelength of 9.1 cm with a pulse repetition frequency of 660 per second.
The system consisted of a transmitter/receiver unit mounted in the navigator's compartment and included an automatic ranging facility which relayed range information into the computer section of a Mark IIC gyro gunsight. The turret featured a small scanning aerial that followed the movement of the guns, and a Cathode ray tube (CRT) display screen positioned adjacent to the gun sight, the image of which was projected on to the gun sight reflector screen via a semi-transparent mirror.
To use, the gunner manouvred his turret until the target blip projected onto the sight reflector screen coincided with the normal gyro sight aiming graticule, at which the point the guns would be correctly aimed, the inbuilt characteristics of the gyro sight almost guaranteeing a hit should the gunner subsequently open fire.
Initially, ranging information was provided only at the transmitter situated in the navigator's compartment and was read-off to the gunner over the intercom, the gunner using foot pedals to set the target range on the sight, however, in production equipment the process was made automatic, the range information being fed electronically directly into the sight, with the navigator's "running commentary" only being retained for the benefit of the rest of the crew.
Village Inn was evaluated and tested by the Telecommunications Research Establishment at RAF Defford using the Lancaster Mark I ND712 and the Lancaster Mark IIIs JB705 and LL737 and subsequently put into production.
The first squadron to use Village Inn operationally was No. 101 Squadron RAF, based at Ludford Magna, in the autumn of 1944, followed soon afterwards by 49, 156 and 635 Squadrons.
Village Inn was eventually produced in three Marks:
AGLT Mark I - initial design.
AGLT Mark II - modified, improved, Mark I - soon discontinued.
AGLT Mark III - scanning aerial mounted remotely from turret. Scan independent of turret's movements.
A similar type of system was produced in the US by the Emerson Company, St Louis, when an Emerson Model III tail turret was equipped with the Emerson APG8 Blind Tracking Radar and fitted to the Canadian-built Lancaster KB805. The system was found to have no advantages over the British system and the project was subsequently dropped.
