DAIMLER-BENZ Aerospace (DASA) is to integrate a new attitude-reference system into the Eurofighter 2000, which dramatically improves a pilot's attitude awareness.

The arc segment attitude reference (ASAR), under development by DASA since 1987, has improved unusual-attitude recovery times by up to 30% in simulator trials.

Following trials earlier this year, when testing was conducted by cockpit assessment working- party (CAWP) pilots from all four nations involved in the Eurofighter programme, the system has been recommended for integration into the Eurofighter helmet-mounted display.

The ASAR is being developed at DASA's Friedrichshafen site following dissatisfaction with traditional pitch ladders used on head-up displays (HUDs), which become hard to follow when a fighter pilot is performing aggressive three-dimensional manoeuvres. The new display is more stationary, requiring less concentration from the pilot and allowing him to respond quickly and correctly in disorientating situations.

The display consists of a circular arc segment, which rotates around a central aircraft symbol according to the aircraft's roll angle. The arc length indicates the pitch angle, corresponding to a schematic representation of the pilot's peripheral field of view of the ground, while angle of attack, is indicated by the dimensions of a delta, in the central symbol.

The trials were carried out in a fixed-base simulator with a generic Eurofighter cockpit layout, early Eurofighter flight-control software and a Lockheed Martin F-16 HUD. The helmet-mounted sight system (HMSS) used in the trials was a monocular display from Kaiser Electronics. The trials included the projection of short-range missile, and gun-aiming symbology on the HMSS.

The CAWP pilots commented that the display gives, " instinctive, simple and always valid information on the aircraft's motion in the pitch and roll axes". As a next step, DASA plans to test the system in a dome simulator with full Eurofighter mission symbology shown on the HMSS.

The present ASAR symbology was developed from a combination of simulator trials and flight tests in a Dassault/Dornier Alpha Jet trainer. The system is already being applied in the HUD of the Rockwell/DASA X-31 high-manoeuvrability research aircraft, and in the helmet-mounted forward-looking infra-red display under development for German air force Panavia Tornados.

Source: Flight International