Review of aircraft landing gear tests as part of structural testing

icaf2023 Tracking Number 16

Aircraft Landing Gear is the one of the most important safety systems onboard ensuring the well-being of cargo and passengers on board the aircraft. It is also the system which gives aircraft ability to take off, land, and manoeuvre on the ground while taxiing. Due to the important safety role in aircraft, Landing Gears have their own requirements defined in regulations and are subjected to many tests going beyond the minimal legal and technical requirements. The full set of Landing Gear tests includes the tests of individual parts, full Landing Gear assemblies, and whole Landing Gear systems. The tests are made in laboratories for initial proof of safety and operation and inflight for full operation testing. Also modern fast and portable digital data acquisition systems make real-time data capture and process possible from various sensors. This capability makes real-time health monitoring feasible for improving test efficiency, detecting faults and dangers or just providing real-time data for possible testing process optimization. The tests are done for various operational conditions beginning from static/strength tests, dynamic tests, to fatigue tests. These tests are performed on specialized test stands in dedicated laboratories and in most of the cases are excluded from being defined as structural tests. Although except from the part of dynamic tests most of the Landing Gear tests share similarities with other types of structural tests in means of load introduction, measurement systems. In this paper authors present a comprehensive review of aircraft Landing Gear tests, including the current state of the Landing Gear tests; modern testing and modelling approaches and capabilities of Landing Gear manufacturers and laboratories; and Landing Gear health monitoring as complementary testing methods and continuing airworthiness support. The review provides examples to show that Landing Gear tests should be considered as part of structural testing even when tests are performed for Landing Gears only. In the end, the paper reviews and discusses the certification requirements for Landing Gears of existing aircraft, as well as a brief outlook on the Landing Gears testing methods and requirements for future new aircraft configuration such as eVTOL.