Sampling Practice Recommendations

The following table outlines the different tests that are available to the Aviation industry. For more detail on the tests performed, click on the Test Kit name (ie, MOB 1, MOB 2).

Aviation

Category Component Test Kit Interval Comments
Engines Piston Aircraft AVI 1 50 hr AVI 1 kit for routine analysis.
Jet Turbine AVI 3 150 hr Test kit includes ferrography to monitor rapid failure modes (e.g. rolling element bearings). For filters with a micron rating of 10 µm (absolute) or less, AVI 2 kits may also be used, and are recommended for 5 µm filter sizes or less.
Turboprop AVI 3 150 hr "
Helicopter Engines AVI 3 150 hr "
Garrett 331 GT-331 100 hr Honeywell certified test analysis for Garrett TPE-331 turboprop engines.
Garrett 731 GT-731 150 hr Honeywell certified test analysis for Garrett TPE-731 turbofan engines.
Garrett APU GT-APU 100 hr Honeywell certified test analysis for Garrett Auxiliary Power Units.
Gears Gearbox AVI 3 150 hr Test kit includes ferrography to monitor rapid failure modes (e.g. rolling element bearings). For filters with a micron rating of 10 µm (absolute) or less, AVI 2 kits may also be used, and are recommended for 5 µm filter sizes or less.
Transmission AVI 3 150 hr "
Rotor AVI 3 150 hr "
Hydraulics Hydraulic system IND 2 150 hr IND 2 kit includes particle counting to monitor fluid cleanliness levels (NAS code).
Special Sampling Considerations
Follow up on abnormal samples AVI 3 WearCheck advises that ferrographic analysis be performed with resamples on equipment that tested abnormal. Filter analysis allows the diagnostician to locate and detect major wear situations. Filter analysis can be performed on any equipment that has a replaceable filter.
Engines with ultra-fine filtration AVI 2 For aircraft engines with ultra-fine filtration (3 µm absolute or less), filter analysis will provide a more comprehensive analysis program. The abnormal wear particles that would normally show up with analytical ferrography are trapped in the filter membrane. Filter analysis will detect these particles.