# SDR 2026FA0000444

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 24, 2026
- Submitted: May 28, 2026
- Operation: General aviation
- Aircraft: [N401KL](https://openairdocs.org/aircraft/N401KL), registered now
- Aircraft serial: 18735P2740
- Aircraft time: 103 hours, 891 cycles
- System (JASC): [5310 · Fuselage Main, Structure](https://openairdocs.org/jasc/5310)
- Part: Structure
- Part number: 23088002
- Part serial: 564529500100
- Condition: Degraded
- Location: Motor Boom
- Part time: 103 hours, 891 cycles
- Stage of operation: DE
- How discovered: O
- Nature of condition: C, E
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2026FA0000444

## Discrepancy

APPROXIMATELY 8 SECONDS AFTER DROID RESTOWING AND SHORTLY AFTER CLIMBING FROM DELIVERY ALTITUDE, ONE PROPELLER CONTACTED AN OBJECT AND BRIEFLY SLOWED BEFORE RECOVERING. ABOUT 1.25 SECONDS LATER, THE SAME PROPELLER EXPERIENCED A SECOND IMPACT AND STOPPED COMPLETELY, LIKELY CAUSING THE BOOM ARM (FWD RIGHT) TO FRACTURE AND THE MOTOR ASSEMBLY TO SEPARATE FROM THE AIRCRAFT.  FOLLOWING THE FAILURE, THE AIRCRAFT EXPERIENCED SIGNIFICANT PITCH AND YAW MOVEMENT DUE TO THE LOSS OF PROPULSION AND IMBALANCE FROM THE DAMAGED ROTOR SYSTEM. DATA ALSO SHOWED SUSTAINED VIBRATION AFTER THE INITIAL IMPACT, INDICATING PROPELLER DAMAGE OCCURRED BEFORE THE BOOM SEPARATED.  THE AIRCRAFT CONTINUED FLIGHT WITH DEGRADED PERFORMANCE AND LATER RECOVERED SAFELY. AIRCRAFT: ZIPLINE, P2ZIP

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