Overview
• Operator: Buddha Air
• Aircraft Model: ATR-72-212A
• Registration: 9N-ANH
• Flight Number: U4-506
• Route: Janakpur (JKR) → Kathmandu (KTM)
• Date: 6 March 2025
• Occupants: 62 people
• Casualties: None
• Aircraft Status: Grounded for inspection
• Investigation: Nepal’s Civil Aviation Authority (CAAN)
⸻
Incident Summary
Buddha Air flight U4-506, an ATR-72-212A, completed a routine flight from Janakpur to Kathmandu, landing safely without incident. However, upon post-flight inspection, it was discovered that one of the nose wheels was missing.
Nepal’s CAAN confirmed that the missing wheel was found near the departure runway in Janakpur, indicating it had fallen off during takeoff.
Despite the nose wheel detachment, the flight crew was unaware of the issue, and the aircraft successfully completed its journey and taxied to the apron in Kathmandu without any apparent difficulties.
⸻
Sequence of Events
Departure from Janakpur
• The aircraft took off normally from Janakpur Airport’s runway.
• No indications of a mechanical fault or abnormal flight characteristics were noted by the crew.
• Unknown to the pilots, the nose wheel detached during takeoff.
Cruise & Landing at Kathmandu
• The aircraft continued its flight without any abnormal handling issues.
• No alerts or warnings regarding nose gear instability were reported in-flight.
• The aircraft landed safely at Kathmandu, taxied to the apron, and shut down normally.
Post-Flight Inspection & Discovery
• During routine maintenance checks, ground crew noticed one nose wheel missing.
• Nepal’s CAAN later located the wheel near Janakpur’s runway, confirming it had detached during takeoff.
• The airline cited a “technical issue” as the cause, pending further investigation.
⸻
Investigation Findings & Initial Analysis
1. Nose Wheel Detachment During Takeoff
• The missing nose wheel suggests a mechanical failure in the nose landing gear assembly.
• Possible causes include:
• Wheel hub fracture or bearing failure.
• Improper wheel installation or loose retaining components.
• Wear and tear leading to structural failure.
2. No Flight Control Issues Noted
• The ATR-72 has a dual-wheel nose gear, meaning one wheel remained intact.
• This likely prevented yawing or handling issues during takeoff, cruise, or landing.
• The lack of abnormal cockpit indications suggests that the nose wheel assembly itself remained structurally sound despite the detachment.
3. Runway Contamination & Safety Concerns
• The nose wheel was found near the departure runway, which raises runway debris and safety risks.
• Nepal’s CAAN will likely assess procedures for runway inspections and aircraft component integrity checks.
⸻
Potential Causes & Contributing Factors
1. Mechanical Failure of the Nose Wheel Assembly
• Possible bearing failure, hub crack, or material fatigue.
• Excessive wear-and-tear due to rough runway conditions at regional airports.
2. Improper Maintenance or Installation
• Potential loose wheel nut or incorrect torquing during maintenance.
• Possible overlooked pre-flight visual inspection issue.
3. Undetected Pre-Existing Structural Weakness
• The aircraft may have had prior stress damage.
• A borescope inspection of the nose gear assembly is required to rule out fatigue cracks.
⸻
Safety Recommendations & Future Prevention
1. Enhanced Nose Gear Maintenance & Inspections
• Conduct thorough nose wheel integrity checks before each flight.
• Implement more frequent checks for ATR-72 nose wheel hubs and bearings.
2. Improved Pre-Flight Visual Inspections
• Strengthen pre-flight walkaround inspections to identify potential wheel abnormalities.
• Train ground crews to detect early signs of nose wheel fatigue or instability.
3. Runway Safety Procedures & FOD Prevention
• Regular runway sweeps at Janakpur Airport to ensure no aircraft parts are left on the surface.
• Ensure CAAN enforces strict maintenance oversight for regional aircraft fleets.
⸻
Conclusion
Buddha Air U4-506 completed its flight safely despite losing a nose wheel during departure from Janakpur Airport.
The crew was unaware of the issue due to no cockpit warnings or flight control abnormalities, likely because the ATR-72 has a dual-wheel nose gear configuration.
While no passengers or crew were harmed, the incident raises concerns over aircraft maintenance, nose gear integrity, and pre-flight inspection procedures.
The Nepal CAAN is investigating the cause, with potential mechanical failure or maintenance error being primary suspects.
The aircraft remains grounded for further inspection before being cleared for service.
⸻
Disclaimer
“This report is based on available information as of 7 March 2025. While every effort has been made to ensure accuracy, the completeness of the details cannot be guaranteed. If you are the rightful owner of any referenced materials and wish them removed, please email takedown@cockpitking.com.”
