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Helmet with Display

Technical Information

Catalogue No: C1243
Category: Head-Mounted Equipment [HMD/NVG/Glasses]
Object Type: Display Unit
Object Name: Helmet with Display
Part No: None
Serial No: None
Manufacturer: GEC Avionics
Division: Flight Automation Research Laboratory [FARL]
Platform(s): Lynx , Tiger Helicopter
Year of Manufacture: circa 1987
Dimensions: Width (mm): 300
Height (mm): 270
Depth (mm): 335
Weight (g): 3,420
Location: Unknown

GEC Avionics Limited
Code K0656


The given weight includes the 2.2m quick-release and 0.6m comms cables. The given size is for the helmet portion.

This helmet is stored in a 330 x 360 x 300 mm, brown fibre-board transport case. The total weight of helmet and cables in the case is 6140g.

A contract from RAE (Farnborough) to build a 40° binocular helmet mounted display system was received in July 1987 by the company research lab FARL. A similar system had previously been delivered to RARDE but that was monocular, so duplication of the parts was necessary to give a binocular capability.
The system comprised a Mk 4 flying helmet with the two optical assemblies attached to it, an Electronics unit and a Pilot’s Control Panel. A junction box allows the Electronics unit to be sited remotely. Each optical assembly contains a one inch monochrome CRT, as well as the necessary optical elements.
The system was delivered in March 1988 and was installed together with the RAE’s Symbol Generator, Helmet Position Sensor and Image Intensifier Camera on the RAE Lynx experimental helicopter as part of a visually coupled system being assembled.
Another variant of this design was supplied for trials on a McDonnell-Douglas KC-10 air to air refuelling tanker. A pair of Teledyne cameras gave a stereo image to assist the boom operator of the tanker to line up the boom. The system was in this case mounted on a ’skeleton’ framework helmet derived from an industrial ‘hard hat’. Yet another trial of this binocular system was made with General Dynamics Land Systems for use in an indirect viewing system for land vehicles. The optical system was also used as a demonstrator for the German PAH1 Helicopter HMD.
These ‘lab’ systems were essentially tools used to evaluate HMD performance and acceptability and yet another 40° x 30° variant was delivered to Southampton University for this work.
In early 1989 the development of a 55° optical system, based on the earlier design, was started which was to have 30mm eye relief, a 12mm exit pupil and a target weight of less than 2.5kg. The optics had fully adjustable eye relief and inter-ocular separation and because of the large field-of-view was driven from a high resolution display offering about 900 lines. The HMD was used by the RAE for Helicopter Simulator research. The RAE system was the first HMD to incorporate an integrated Eye Tracker.

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