Pressure washing is a fast, appealing way to remove grease, hydraulic fluid, brake dust, and salt from aircraft landing gear. But high-pressure water, improper cleaning agents, and rough technique can do significant harm, compromising safety, increasing maintenance costs, and shortening component life. This article explains how pressure washing can damage landing gear, what parts are vulnerable, and safer cleaning recommendations.

How Pressure Washing Can Cause Damage

• Seal and Oring failure: High-pressure jets from pressure washing can cut, abrade, or dislodge rubber seals and Orings in actuators and shock struts, and loosen or remove sealants applied to bushing mating surfaces, etc. Damaged seals permit fluid leaks and contaminant ingress.
• Water intrusion: Forceful spray can drive water and detergents past seals into wheel bearings, axle cavities, and brake assemblies, washing out grease and causing accelerated wear, pitting, and corrosion.
• Corrosion promotion: Trapped moisture beneath coatings, inside bolt holes, or in mating surfaces can accelerate corrosion, especially when combined with salt or alkaline detergents. High-pressure spray can also strip protective paint or primers.
• Damage to hydraulic and electrical components: Direct high-pressure impact can nick hydraulic lines, fittings, or electrical harnesses (including connectors and sensors), leading to leaks, shorts, or sensor failures.
• Erosion of soft metals and bearings: Repeated high-pressure cleaning can erode aluminum, magnesium, plated surfaces, and bearings, reducing fatigue life and fit tolerances.
• Dislodging lubrication and protective films: Grease and corrosion inhibitors that are meant to protect moving components can be removed by strong jets, leaving parts exposed.
• Contamination of critical interfaces: Forceful spray can force contaminants into torque joints, actuator pistons, and other fitted interfaces, impairing function.

Vulnerable Landing Gear Areas

• Shock strut seals and piston rods
• Bushings, eye bolts, and spherical bearings
• Actuator ports, fittings, and hoses
• Electrical connectors, proximity switches, and proximity sensors
• Fastener holes and torque joints
• Protective coatings

Common Real-world Failure Modes Linked to Pressure Washing

• Bearing corrosion and premature failure after water ingress
• Hydraulic leaks from damaged seals or nicked hoses
• Corroded fasteners requiring unscheduled replacement
• Adhesive or bonded-interface degradation
• False readings or failures in proximity sensors due to water ingress

Cleaning Recommendations

• Always follow manufacturer and OEM guidance and operator maintenance program requirements. These override general practice.
• Dry wipe-down is the safest method.
• Do NOT remove all grease from torque joint bushing areas. Grease squish-out is normal and helps “seal” the torque joint to ward off contaminate and moisture intrusion.
• Use manufacturer-approved cleaning agents only. Avoid strong alkaline cleaners or solvents that remove protective films or attack seals. Only use OEM-approved cleaning agents and detergents as directed.
• Use steam or controlled soft-wash systems (if OEM-approved). Steam cleaning at regulated temperatures/pressures can remove contaminants without forcing water into seals.
• After cleaning, dry components (towel dry or low-pressure air, never compressed air), re-lubricate, and reapply corrosion inhibitors per maintenance instructions.
• Perform a focused inspection of seals, bearings, hydraulic fittings, and protective coatings to detect any damage early.
• Ensure cleaners and maintenance staff are trained and require sign-off that OEM procedures be followed.