A-4 HUD Pilot's Display Unit

Technical Information

Catalogue No: C0003
Category: Head-Up Display [HUD]
Object Type: Display Unit
Object Name: A-4 HUD Pilot's Display Unit
Part No: 229D2251
Serial No: 06
Manufacturer: Unknown
Division: Unknown
Platform(s): A-4 Skyhawk 
Year of Manufacture: 1970
Width (mm):
Height (mm):
Depth (mm):
Weight (g):
Location: Archive Object Store

PDU Type 546


The success of the A-7 Corsair HUD was followed by a system for the H, M and N variants of the McDonnell Douglas A-4 SkyHawk. About 465 systems were delivered, from about 1970 to 1978 to the U.S and elsewhere. This remains one of the smallest HUD's the company has made with a Display Unit containing little more than the CRT projecting through a 3" optic giving a 20deg TFoV. The system was distributed into the PDU , Video Signals Unit, HVPSU and the Electronics Unit. The VSU had one of the noisiest fans ever! The A-4 was the first product of a new concept a HUD weapon aiming computer or HUDWAC. The rationale was that most of the information needed for weapon aiming, such as height, airspeed and altitude, was required within the same computer that generated the HUD symbology. It was a simple matter to increase the computer speed and to expand the store size to carry out the weapon aiming computation. This system finally reached an 8k instruction PROM store. This HUD is marked PDU Type 546 and has Serial Number 06 so it was probably manufactured around 1970. It has been modified with an internal battery powered LED and graticule for use as a lecture demonstrator.

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