|Category:||Head-Up Display [HUD]|
|Object Type:||Display Unit|
|Object Name:||A-4 HUD Pilot's Display Unit|
|Year of Manufacture:|
|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 20° 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 PDU has no Identification Plate and is fitted with part of the Mounting Tray. The Optics is Serial No. 0004 which shows that this is perhaps an early test unit.