FAA Aviation Mechanic Airframe (AMA)Airframe InspectionMedium
During an inspection of a fuel tank access panel on a transport category aircraft, a technician notices the sealant around the panel has cracked and lifted. Why is this discrepancy considered a significant airworthiness concern requiring prompt correction?
- AIt only matters if the aircraft operates in cold climates
- BCompromised sealant can allow fuel leakage and moisture/contaminant intrusion, creating fire hazard and corrosion risk
- CIt has no effect on airworthiness since fuel tanks are self-sealing by design
- DIt only affects the aircraft's paint appearance and cosmetic value
Show answer & explanationAnswer & explanation
Correct answer: B. Compromised sealant can allow fuel leakage and moisture/contaminant intrusion, creating fire hazard and corrosion risk
Fuel tank sealant that has cracked or lifted can lead to fuel leaks, which pose a serious fire hazard, and can also allow moisture and contaminants to enter, promoting corrosion inside the tank structure; both conditions must be corrected before further flight.
Why the other options are wrong
- A. Sealant degradation is a concern in all climates, not limited to cold weather
- C. Fuel tanks are not inherently self-sealing; sealant must be maintained to prevent leaks
- D. Fuel tank sealant integrity is a structural/safety issue, not merely cosmetic
Fuel Tank Sealant Inspection
Inspection of fuel tank access panels and seams for cracked, lifted, or deteriorated sealant that could allow fuel leakage or contaminant intrusion.
- Cracked sealant can cause fuel leaks, a serious fire hazard
- Moisture intrusion through failed seals promotes internal corrosion
- Sealant repairs must use approved fuel-resistant sealant per maintenance manual
Memory trick: Broken sealant is a leaky secret door for fuel and moisture