MACH (Monitoring Aircraft Health) - SWRDA

The first project in MACH concerns the Health Monitoring of Landing Gear Systems. The project
combines QinetiQ health monitoring technology and Messier-Dowty's expertise in manufacturing
landing gear. This will consider the monitoring of the power electronic$ system as well as the actuators.
Deployment and retraction of the landing gear makes large demands on the power electronics system
and it is vital that it can cope with this sudden increase in demand. Health Monitoring of the landing
gear systems offers the promise of safer, lighter landing gear.
The outputs from the different work packages will be specific to the different parts of the landing gear
being considered. For the shock absorber work package, this will be in the form of a novel sensing
device, for measuring the level of absorbed nitrogen. For the structural load work package, the output
will be an algorithm for assessing loads experienced by the landing gear under normal service usage,
and for the hydraulic actuation programme it will be an algorithm for assessing actuator health fusing
the data output from one or more COTS sensors identified within the project. In each case, a suitable
demonstration of the developed technology will be provided, involving either full scale rig tests or
service data, or a combination of the two.
The deliverables will be;
1. A demonstration of an absorbed nitrogen sensor on a suitable test rig.
2. A report describing the technological solution for measuring~ the level of absorbed nitrogen
within the landing gear shock absorber, including a description of the demonstration of the
sensor using dedicated rig tests
3. A report describing the development of a neural network algorithm for determining the loads
experienced within a landing gear structure, together with a demonstration derived from actual
service data.
4. A demonstration of the use of algorithms to analyse representative service-type data.
5. A report describing the development of an algorithm for monitoring the health of landing gear
hydraulic actuators, including details of a demonstration of the accuracy and reliability of the
algorithm using rig test data