Head-up – or head-down?

By John Croft

Though the US and European safety regulators require operators to equip with head-up displays (HUDs) to gain lower approach minimums (aka operational credit) when using enhanced vision systems (EVS), researchers caution that a lower-cost head-down display (HDD) solution may provide equivalent safety for aircraft with two pilots. Operational credit is a key cost-benefit driver in equipping with EVS, and by association, a HUD.

Simulations completed at the Institute of Flight Guidance and Control in Germany show that if one pilot monitors flight instruments and the EVS image on an HDD for while the other pilot monitors the instruments and looks outside the cockpit for visual cues, "there seems to be no loss of situation awareness. Further on, there is no significant trend that use of the EVS head-down display leads to a higher workload compared to the EVS HUD approach", the researchers report.