S-3 Air Data Computer (space model)

The RAA contains a number of models of equipment and aircraft. The equipment models were used as a marketing aid and often to ensure that the production unit will fit in the space; this was particularly true for Head Up Displays. Such equipment models will have minimal or no functionality. Models might  just be used as weighted units or as cockpit lighting evaluation units. The HUD used on the YF-16 was of the correct weight and envelope but only mounted the Spin 'chute button (a feature only required for the early test flights). Many of these models were made by professional model makers from the original drawings and could be quite expensive; alternatively the real hardware would be used.

The aircraft models range from the simple small scale kits to quite large display items. The large model aircraft were often a marketing tool from places like Airbus or Boeing but may be found in Boardrooms or Reception areas wheras the small models may be given as a visitor handout. Those models made from kits have largely been brought in from home but are useful to illustrate the platform alongside the equipment. The large models will be hugely expensive.

In 1981 Instrument Systems Division began the design of a new generation of Air Data Computers designed for the combined USAF and USN Standard Central Air Data Computer (SCADC) programme. The system was designed to fulfil the retrofit requirements of 38 different aircraft types and to do so with only four configurations. The aircraft types include the following:-

A-4M and TA-4J Skyhawk, A-6E/F, KA-6D and EA-6A Intruder, EA-6B Prowler, TC-4C Gulfstream, A-7D/E/K and TA-7C Corsair II, C-2A Greyhound, E-2C Hawkeye, KC-135 Stratotanker, C-5A/B Galaxy, C-141A/B Starlifter, F-111A/E/D/F, FB-111A, EF-111A, F-4C/D/E/G/J/N/S, and RF-4B/C Phantom and the S-3A/B and US-3A Viking. In 1992 an order for a further 290 units was received, being the eighth option, bringing the total procured to 5552 units. 387 units of the SCADC system were at this time being supplied for the F-14 Tomcat.

The high commonality was achieved with a unique software re-configurable design. Output parameters, ranges and scalings are selected for each aircraft type by the software, which recognises the host from a code wired into the aircraft connector pins. The SCADC core hardware set provides over 80% of the hardware in every application and the remainder is addressed by one or two special-to-type modules. A multiplicity of analogue interfaces can be handled and the Mil-Std 1553 DataBus is also a feature. Production commenced in 1985 with first deliveries the following year and in 1989 these deliveries surpassed 4,000 units. In addition in 1988 ISD received the Queen’s Award for Technological Achievement for SCADC.