RAF Stenigot ACE HIGH relay station, Lincolnshire

RAF Stenigot is a former World War Two Chain Home radar station situated in Lincolnshire to give warning of the approach of the Luftwaffe to Nottingham, Sheffield and the central midlands. It was retained as a radar station after WW2 as part of ROTOR phase 1 but was then upgraded to a tropospheric relay station under the ACE High NATO Communications program in 1958. The site was closed in the late 1980’s and most of the site was demolished by 1996. All that remains are some of the WW2 era radar transmitter building, the tropospheric dishes (now lying on the floor) and a WW2 era chain home mast that is now used by the RAF Aerial Erector School and is grade II listed. The site would have had a police house, transmitter, receiver and power supply buildings of which only the concrete bases survive to indicate where these stood.

ACE High

ACE High was an abbreviation for ‘Allied Command Europe’ and was an ultra high frequency communications system that worked on the principal of ‘tropospheric scatter’ to enable communications to travel further than previous ‘line of site’ systems that needed lots of relay stations to be reliable.

Tropospheric Scatter vs. Line of Sight (US Army)
Tropospheric Scatter vs. Line of Sight (US Army) Click to enlarge

The transmitting distance of the ACE High system was often upto 300km between stations. The transmitters broadcast between 832.56 to 959.28MHz at a power of around 10 kilowatts. There were around 80 main sites located in 9 different NATO Countries. The 5 sites in the UK were in the Shetland Islands, Mormond Hill in Aberdeenshire, Brizlee Wood in Northumberland, Detling in Kent and Stenigot in Lincolnshire.

Due to the advent of microwave better microwave technology in the late 1980’s the ACE High system became redundant, the stations were closed and the frequencies turned over to civilian use. The Soviets had a similar communications system that operated on similar principles and was called the BARS system that stretched from Germany all the way to Russia.

Modified: 1st Apr 2017