The flight-deck displays shown in Figures 15.16 through 15.18 are on the instrument panel in front of the pilot, who must look down for flight information – more frequently in critical situations. When flying close to the ground or chasing a target, however, pilots should keep their head up, looking for external references. This inflicts severe strain on pilots who must frequently alternate the head-up and head – down positions. Engineers have solved the problem to a great extent by projecting the most important flight information (both primary and navigational data) in bright green light on transparent glass mounted in front of the windscreen. With a head – up display (HUD), pilots can see all necessary information without moving their head and, at the same time, they can see through the HUD for external references. Figures 15.17 and 15.18 show a modern HUD.
Initially, a HUD was installed in combat aircraft but the technology recently has trickled into civil aviation as well. HUDs are being installed on most new medium – and large-sized commercial transport aircraft if requested by operators.
15.8.5 Helmet-Mounted Display
Although the HUD has relieved pilots from frequently looking down, the head-up observation is restricted to forward vision only. Military aircraft pilots needed to ease the workload while making a peripheral visual search when the HUD is no longer in the line of sight. Engineers designed a novel device that projects flight information on a helmet-mounted visor. Now pilots can turn their head with all the relevant information still visible on the transparent visor, through which external references can be taken.
Figure 15.18. Typical civil aircraft flight deck
Table 15.10. HOTAS control buttons