Landing a helicopter on the deck of a ship in poor visibility is a big challenge even for the most experienced of pilots. Researchers at the Technical University of Munich (TUM) have developed an assistance system that displays key information in the visor of the pilot’s helmet-mounted display. This permits precise landing approaches - even in adverse weather conditions.
As the pilot aims for the helicopter landing platform on the deck, the ship heaves, pitches and rolls violently in the storm, with visibility made worse by the sea spray and dense cloud cover. The helicopter must maintain a safe distance from the superstructures on the upper deck to avoid contact with the aircraft’s rotor blades - but also needs to be far enough from the edge of the deck to avoid the overhanging fuselage pulling it backwards into the sea. Pilots often have to make repeated attempts at the landing maneuver.
Researchers at TUM have modelled this challenging and dangerous situation using the helicopter simulator at the Chair of Helicopter Technology. They are developing solutions to make it safer for pilots to execute approaches and landings on ships and ocean platforms - even in bad weather with high seas and low visibility.
"On the open seas, there are generally few points of visual reference to guide pilots," explains Tim Mehling, a doctoral candidate at the Chair of Helicopter Technology. Pilots are therefore frequently forced to switch their focus from their landing target - the ship’s deck - to glance at the cockpit instrument panel.
"On top of that, even the best pilot’s concentration will slip after the 20th approach attempt," says Mehling. His idea: creating a helmet-mounted, real-time display that presents all relevant information from the helicopter and the ship - using graphics that are superimposed on the pilot’s view outside the cockpit. This technology is known as augmented reality, or AR for short.
Mehling began by developing a highly realistic simulation of the environment at sea. At the same time, he worked with experienced navy test pilots and applied national and international standards to determine what information pilots need for a safe approach. "We developed appropriate icons for every phase of the landing. The coordinated icons are automatically displayed in the visor during the corresponding flight phase."
The helmet displays a visual attitude indicator as well as key helicopter parameters. The software can also use imaging data to automatically detect the ship’s deck and visualize the ideal approach, which resembles a sort of 3D "slide" in the display. "If visibility is lacking due to bad weather, the pilot can glide down this stable virtual slide to make a safe landing," says Mehling.
Four test pilots with experience in seaborne operations with the German military and in the private sector have tested the pilot assistance system and given it the thumbs-up. In the next stage of development, it will be tested by pilots working in a wide range of flight ops scenarios. The results will then be used for further optimizations of the system.