Aircraft Corrosion: Inspection, Prevention, and Treatment Guide

Aircraft corrosion poses serious safety and value concerns for owners. Understanding corrosion inspection, prevention strategies, and treatment costs protects your investment and ensures continued airworthiness.

Types of Aircraft Corrosion

Surface Corrosion:

• Most common type
• Appears on aluminum skin surfaces
• White or gray powdery substance
• Can usually be treated if caught early
• Cost: $500-$5,000 treatment

Intergranular Corrosion:

• Attacks along grain boundaries
• Invisible from surface initially
• Discovered during detailed inspection
• Can compromise structural integrity
• Cost: $5,000-$50,000+ depending on extent

Pitting Corrosion:

• Deep holes in aluminum
• Concentrated in small areas
• Structural concern if deep
• May require part replacement
• Cost: $2,000-$20,000

Stress Corrosion:

• Cracks from corrosion plus stress
• Most serious type
• Can cause catastrophic failure
• Often requires part replacement
• Cost: $10,000-$100,000+

Common Corrosion Locations

High-Risk Areas:

• Battery compartment: Battery acid exposure
• Wing attach points: Moisture traps
• Control surfaces: Moisture in hinges
• Engine mounts: Heat and moisture
• Wheel wells: Road salt, moisture
• Lower fuselage: Standing water
• Exhaust areas: Acidic byproducts

Corrosion Inspection Costs

Basic Inspection:

• Annual inspection corrosion check: Included ($1,500-$3,000 annual)
• Dedicated corrosion inspection: $500-$1,500
• Borescope inspection (hidden areas): $500-$1,000

Detailed Inspection:

• Panel removal inspection: $2,000-$5,000
• Wing inspection (extensive): $3,000-$8,000
• Complete airframe inspection: $5,000-$15,000

Corrosion Treatment Costs

Minor Surface Corrosion:

• Cleaning and treatment: $500-$2,000
• Protective coating application: $300-$1,000
• Monitor during annual inspections

Moderate Corrosion:

• Remove corrosion, apply treatment: $2,000-$10,000
• May include minor part replacement
• Protective measures required

Severe Corrosion:

• Structural component replacement: $10,000-$50,000+
• Wing spar replacement: $30,000-$80,000
• May render aircraft uneconomical to repair
• Total loss if too extensive

Impact on Aircraft Value

Value Reduction by Severity:

• Minor corrosion: 5-10% value reduction
• Moderate corrosion: 15-30% reduction
• Severe corrosion: 30-50% or total loss
• Corrosion-free aircraft: Premium of 5-15% over average

Corrosion Prevention

Storage Methods:

• Hangar storage: Best corrosion prevention
• Dry climate: Arizona, New Mexico ideal
• Avoid coastal areas: Salt air accelerates corrosion
• Climate control: Reduces moisture

Preventive Treatments:

• CorrosionX: $200-$500 annual treatment
• ACF-50: $150-$400 annual
• Boeshield T-9: $100-$300
• Professional application: Recommended for thoroughness

Operational Prevention:

• Fly regularly (prevents moisture accumulation)
• Keep aircraft clean
• Address leaks immediately
• Avoid puddles and standing water
• Remove battery during storage

Regional Corrosion Risk

Low Risk (Dry Climates):

• Arizona, New Mexico: Minimal corrosion
• Nevada, parts of California: Low humidity
• Mountain states: Generally dry
• Premium value for desert aircraft

High Risk (Humid/Coastal):

• Coastal areas: Salt air extremely corrosive
• Southeast: High humidity year-round
• Great Lakes: Moisture and winter salt
• Requires aggressive prevention program

Buying Aircraft with Corrosion

Due Diligence:

• Professional corrosion inspection required
• Borescope hidden areas
• Remove panels for full assessment
• Get treatment/repair estimates
• Reduce price by 150-200% of repair cost

Walk-Away Scenarios:

• Severe structural corrosion
• Wing spar corrosion beyond limits
• Multiple areas with deep corrosion
• Repair costs exceed 30% of aircraft value

Frequently Asked Questions

How much does aircraft corrosion repair cost?

Minor surface corrosion: $500-$2,000 treatment. Moderate corrosion: $2,000-$10,000. Severe structural corrosion: $10,000-$50,000+. Wing spar replacement: $30,000-$80,000. Extensive corrosion may render aircraft uneconomical to repair. Prevention far cheaper than treatment.

How to prevent aircraft corrosion?

Hangar storage best prevention. Apply corrosion inhibitors annually ($150-$500). Fly regularly to prevent moisture accumulation. Avoid coastal areas and high humidity. Keep aircraft clean. Address leaks immediately. Desert storage (Arizona, New Mexico) minimizes corrosion risk significantly.

Does aircraft corrosion reduce value?

Yes significantly. Minor corrosion: 5-10% value reduction. Moderate: 15-30%. Severe: 30-50% or total loss. Conversely, corrosion-free aircraft command 5-15% premium over average. Desert-based aircraft particularly valued for corrosion-free history.

Should I buy aircraft with corrosion?

Depends on severity and price. Minor surface corrosion: Acceptable with price reduction and treatment plan. Moderate corrosion: Major price discount required (150-200% of repair cost). Severe structural corrosion: Walk away—safety risk and uneconomical repairs. Never buy without professional corrosion inspection.

How to inspect for aircraft corrosion?

Annual inspection includes basic corrosion check. For pre-purchase: Hire A&P for dedicated corrosion inspection ($500-$1,500). Use borescope for hidden areas ($500-$1,000). Remove panels in high-risk areas ($2,000-$5,000). Check battery compartment, wheel wells, wing attach points, control surfaces thoroughly.