Fault Tree Interval Analysis of Complex Systems Based on Universal Grey Operation

Figure 3

Fault tree of an aircraft landing gear retraction system, where T is a landing gear retraction system fault; M1 is an actuating cylinder fault; M2 is a control system fault; M3 is a hydraulic system fault; M4 is a piston rod fault; M5 is a sealing ring fault; M6 is an end eyelet fault; M7 is a hydraulic pump fault; X1 is a cylinder fracture; X2 is a seized piston rod; X3 is a loose piston rod; X4 is a fractured piston rod; X5 is a mechanically damaged sealing ring; X6 is an aging and cracking sealing ring; X7 is a chemically corroded sealing ring; X8 is an eyelet bolt fracture; X9 is an eyelet rotation; X10 is the failure of the pressure switch; X11 is the failure of the electromagnetic switch; X12 is the failure of the safety valve; X13 is oil leakage from the hydraulic line; X14 is an air lock fault; X15 is a fracture of the pump plunger piston spring; X16 is oil leakage from the pump rotary joint; X17 is a damaged pump motor; X18 is oil contamination; X19 is a broken hard pipe; X20 is a break in the accumulator.