Metering Pin Optimization and Spatial Tolerance Sensitivity in Articulated Aircraft Landing Gear

Metering-pin profiles govern stroke-dependent hydraulic resistance in articulated aircraft landing gear. This study combines multiobjective optimization, analytical diameter-error amplification and spatial sensitivity screening in a twin-wheel vertical-drop model. The model uses an initial absolute gas pressure of 2.95 MPa and defines load factor using a single-wheel static reference. The optimized pin gives a peak single-wheel load factor of 1.21447 over a 2 s response and first-compression energy-utilization efficiency of 95.302%, compared with 1.62791 and 57.268% for a constant pin. Both numerical design targets are met at the prescribed drop condition. Five independent optimization runs assess nominal performance. A 64-case ANSYS 2022 R1 design and 50,176 sensitivity evaluations quantify dimensional effects around the baseline profiled pin. The final-hypervolume coefficient of variation is 0.60%; extending the generation budget improves hypervolume by 0.210–1.200%, indicating remaining finite-budget search dependence. Main-effect and total-order estimates identify a leading station group near 140–170 mm, with uncertainty in detailed ordering. The results support conditional geometric screening. Assembly-specific drop tests and manufacturing-capability measurements are required before production tolerances or qualified landing performance can be established.