Flight Assistant Systems

Research Area “Emergency Landing Assistance Systems”

ELA Foto: FernUniversität

A loss of thrust constitutes a crucial issue for every pilot and requires fast as well as target-oriented action. There are several reasons for a total loss of thrust, e. g. a bird strike in all engines which happened during the flight UA 1549 with an Airbus 320 in 2009. The subsequent emergency landing was conducted by captain Sullenberger on the Hudson River. In sport aircrafts often only a single technical problem with the engines can lead to an emergency situation. Unfortunately, lack of fuel is often the cause.

Whereas basically no engines are used during gliding, even a normal aircraft becomes a glider after a total loss of thrust. In this case, the objective of the pilot is to follow a suitable flightpath so that the aircraft reaches the runway threshold of an appropriate altitude. Thereby, the pilot has to consider the gliding properties of the aircraft and, especially for slow flying aircrafts, the current wind situation (this is particularly important for drones). Because of the fact that the gliding properties significantly differ in turning and straight-ahead flight, the determination of a flightpath is difficult.

It is obvious that a pilot must have a lot of experience in order to consider the above mentioned influencing factors correctly to determine a suitable flightpath. Since a rapid decision for a runway is required and various influencing factors such as wind and flight behavior can only be estimated intuitively, there is a great danger that the emergency landing fails. Once a decision is made, it can only hardly be corrected. E. g. Capt. Sullenberger had a very short time for his decision and it was finally just possible to land the aircraft on the Hudson river – fortunately a good decision.

Engine-out Emergency Landing Assistant (ELA)

ELA-Method (Videos)

Emergency Landing Field Identification (ELFI)


  • The underlying aircraft models of the ELA approach are consciously kept very simple to achieve high speeds in the calculations of the gliding paths. They are mainly based on the sink rates in straight-ahead and turning flight with various roll angles. The related optimal gliding speeds are determined with respect to the constrains (e. g. wind direction and speed). Because of this simplified flight models it has to be evaluated how the ELA gliding paths prove in real scenarios. Therefore, simulation systems with growing realism are used by applying flight simulations in Matlab and X-Plane 11. While a human pilot compensates the impact of the simplified aircraft models very well, he is only capable to test a few gliding paths per time unit. Hence, autopilots are developed for the above mentioned simulators which facilitate more objective and extensive analysis. Based on simulations investigations in which cases ELA guides the damaged aircraft to a runway are performed. Furthermore, the influence of flawed wind estimations with the offline as well as the online version of ELA will be analyzed. After a successful completion of the simulation based evaluations, test flights with different real aircraft will be executed. As with the simulations, fixed wing aircrafts as well as rotary-wing aircrafts will be examined.

  • Prof. Dr.-Ing. Wolfram Schiffmann
    Marius Klein, B. Sc.
    Andreas Klos, M. Sc.
    Dipl.-Ing. David Osten
    René Titze, M. Sc.