Hawker MLG Microswitch Cable Routing Worth A Second Look

January 2022

The distance between the Hawker MLG (main landing gear) microswitch cable and the adjacent MLG tire is of close tolerance and great import.

Duncan Aviation Hawker technicians have noted broken or missing cable ties, migrating cables, and obviously misrouted microswitch cables on some Hawker MLG legs. Any of these conditions could lead to contact between the tire and the cable subsequently damaging the microswitch cable. A damaged cable can lead to malfunctioning thrust reversers and pressurization issues.

Frequent visual inspection of routing before flight is an excellent tool to help mitigate possible cable contact with the tire. Routing of these cables is very specific and is illustrated clearly in the Hawker AMM (see illustration below). Take care to ensure proper orientation and cable tie placement.  

Duncan Aviation also recommends checking for excessive motion of cables with respect to clips, ties, and cable guides. A simple routine of checking these wires and their routing could save you from an AOG situation.