German tech tested automatic landing system for smaller airports

Successful automatic landing with vision assisted navigation/ Image: TUM
Successful automatic landing with vision assisted navigation/ Image: TUM

Autoland or automatic landing systems for aircrafts enable airliners to land in weather conditions that would otherwise be dangerous or impossible to operate in. Major commercial airports have the infrastructure necessary to ensure the safe navigation of the aircraft; their autopilot follows radio signals transmitted by ground-based antennas. But the smaller airports usually don’t have such an infrastructure. Now it seems like not only major airports but even smaller airports can have automatic landings for aircraft.

Recently, researchers at Technical University of Munich (TUM) in collaboration with Technische Universität Braunschweig demonstrated a completely automatic landing system for aircraft with vision assisted navigation that they say works without the need for ground-based systems.

Automatic landing is essential, especially in the context of the future role of aviation,” says Martin Kugler, a research associate at the TUM Chair of Flight System Dynamics.

Infrared camera image showing selected runway./ Image: TUM
Infrared camera image showing selected runway./ Image: TUM

The technology, which is being developed as a part of the German federal government’s C2Land program, relies on GPS to navigate effectively.

The major problem with the GPS signals is they are susceptible to measurement inaccuracies, for example, due to atmospheric disturbances, which the aircraft’s GPS receiver can’t always reliably detect. And hence the pilot would still have to take manual control before the aircraft touched down if the systems were using GPS alone.

To overcome this problem, the TU Braunschweig team developed an optical reference system which is equipped with both a visible-light and an infrared camera that provides data under conditions with poor visibility.

As the aircraft reaches near the airport, onboard image-processing software lets the system determine where the aircraft is relative to the runway based on the camera data it receives. The aircraft’s autopilot then uses this information together with the GPS data to guide the aircraft safely into a landing.

In late May, the team field tested – as reported in the journal ION – the system and it was successfully used to land a modified diamond DA42 at a small airfield. You can watch the landing in the video given below.

The cameras already recognize the runway at a great distance from the airport,” says pilot Thomas Wimmer. “The system then guides the aircraft through the landing approach on a completely automatic basis and lands it precisely on the runway’s centreline.”