[ ] SIENA

Stimulation Initiative for European Neural Applications

Esprit Project 9811



Case Studies of Successful Applications



Helicopter Flight Data Analysis (HFDA)

Company background

Eurocopter is a European company, manufacturing both civilian and military helicopters. The company is a joint venture between French Aerospatiale and German MBB. The application has been designed in 1990 for Aerospatiale Helicopters which become later Eurocopter in Marseilles.

The problem

Flight recorders provide a huge amount of data which are seldomly used by the helicopter manufacturers. Most of the time, flight recorder are used only in case of crash or disfunction of the helicopter. On the other hand, structural stress of the helicopter on the miscellaneous organs is derivated from the flight conditions. Bad flight conditions will lead to a higher stress on the blades and the body while quiet flight will less agress these part. The reason for which the recorded flight parameter are not compiled is because the computer interpretation was not adequat due to highly nonlinear cross correlation between different signals.

Neural network application

The HFDA has been developped using the NLS (Nestor Learning System) a software solution. Basic function of HFDA includes viewing signals like vertical acceleration, altitude, engines RPM and torque, horizontal speed. Then, signal are selected by the operator and, initially, flight phases (about 40 differents) are delimited by the operator and the neural network is teached with the flight category (take off for example) to which the set of signal belong, for a given time period. When the HFDA has been trained, the system can start to recognize flight phasis. HFDA feature dynamic category addition and incremental learning.

Benefits

HFDA analyses one hour of flight data in about 5 minutes on a 486 PC platform while a high level human expert will spend few hours for the same tedious task. The correlation with a human expert is close to 90%. The system quickly detects strange flight configurations and high stress configurations.

Generalization

This application can be generalized to virtually any kind of data analysis like aircraft flight recorder analysis, truck analysis, locomotive analysis and industrial process analysis. The availability of hardware neural networks chips with real time learning capability allows to design low cost condition monitoring systems to prevent failure.

Contact person

Mr. Carlier, Eurocopter Aeroport International 13700 Marignane. Fax +33 42 85 86 05