NDTnet 1998 Aug, Vol.3 No.8

Abstract

For take-off and flight planning pilots require the actual gross weight and the centre of gravity of the aircraft. For the AIRBUS A330/A340 a so called Weight and Balance System (WBS) was certified in 1993. It is an on-board system which measures
• Gross Weight (GW),
• Centre of Gravity (CG)
on-ground and displays these values in real-time in the cockpit. The load on each wheel, caused by aircraft weight, is measured by 32 inductive sensors (A340 application) mounted on lugs, milled out of the landing gear axle or bogie beam. Due to the extremely high sensitivity of the sensors (working area l0µm under full load) careful installation, adjustment and a complex system calibration is required.

The disadvantages of the current system could be extremely reduced by using NdT methods for on-line measurements!
Within a European research project it shall be demonstrated that the magnetic Barkhausen noise can be used to measure the actual weight of an on-ground aircraft in real-time. Extensive laboratory testing have to be carried out to discover the accuracy, reliability and robustness of Barkhausen Noise Sensors operating in the harsh environment of aircraft landing gears. The compensation of external influences and parameters on the micromagnetic effect is one of the challenges.
Basis of the expected results is the extremely high and reproducible sensitivity of Barkhausen Noise to the stress and strain variations in the loaded components of the aircraft under weight increments.

Using Barkhausen Noise Sensors the current WBS could be simplified:

• reduction of sensor numbers (from 32 to 8) and costly system calibration
• simple sensor mounting and calibration
• deletion of expensive sensor mounting lugs

The research, development, manufacturing and testing of a Barkhausen Noise Sensor prototype (which is able to determine the actual aircraft weight under operation of an aircraft environment) and its mechanical adaptation to the landing gear are the two main objectives of the project.

Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00

Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:

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