Probable cause
The loss of the number one hydraulic system fluid and hydraulic pressure during cruise due to the failure of the bolts that secure the hydraulic pump's cover.
NTSB analysis
The helicopter pilot observed a caution light for the number one hydraulic system and a corresponding complete loss of hydraulic system pressure for that system. The pilot declared an emergency and performed a run-on landing. A postincident examination of the system's hydraulic pump revealed that two of its cover attachment bolts had separated. The bolt heads fractured in tension from their shanks via intergranular cracks which initiated at the filet radius between the bead and the shank. The bolt fractures exhibited intergranular fracture features over 90 percent of the surface. The operator’s incident report safety recommendation stated that the pump's cover bolts should be replaced at overhaul; however, it is not required. The helicopter had accumulated 269 hours since overhaul.
Text from the NTSB. Open the NTSB docket for CEN09IA618 for the full record.
Event
- Date
- Jul 1, 2009
- Type
- Incident
- Place
- Peoria, Illinois
- Nearest airport
- General Downing - Peoria Iap (PIA)
- Highest injury
- None
- Weather
- Visual (VMC)
Bell 230
- N-number
- N880SF
- Category
- Helicopter
- Operating rule
- Part 135 (charter and commuter)
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.