Development of a tunnel-in-the-sky display for helicopter noise abatement procedures

Research on helicopter noise abatement at DLR has led to the development of a pilot assistant display for following prescribed noise-optimised landing procedures. An intuitive tunnel-in-the-sky display was chosen in order to reduce pilot workload during complex manoeuvres. The tunnel representation allows the pilot to anticipate the coming flight path. This has led to improvements in flight path accuracy compared to flights with a standard primary flight display with target indicators only. Trajectory generation is performed partly during flight which allows the update of the displayed trajectory relative to the current helicopter position. After selecting the desired noise abatement procedure, landing place and approach direction, a transition trajectory is generated that leads the pilot to the entrance point of the actual procedure. Performance of the tunnel-in-the-sky display has successfully been demonstrated during ground-based simulator tests with two pilots and in first airborne test flights. The display will be used for upcoming flight test campaigns with DLR’s research helicopter ACT/FHS.