- Date
- July 16, 1991, 20:25 local (Jul 17, 1991, 00:25 UTC)
- Place
- Savannah, GA
- Injuries
- 5 uninjured
- Damage
- Minor damage
- Phase of flight
- Enroute
- Aircraft
- N922HAde Havilland DHC-8-102
- Weather
- Visual (VMC) · Dusk
- Status
- Completed · report March 9, 1993
- Report
- Approved by Office Director
- FAA report
- 19910716033829I
- Case key
- 8346
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the incident.
On this page
Probable cause
The inadequate inspection procedures which allowed the loss of torque on the top retraction fitting attachment bolt which subsequently failed in fatigue. Factors were the loss of hydraulic fluid through a severed line, and the corrosion of a hydraulic quantity limiting valve.
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
After flt 4317 took off, the main lndg gear did not retract. The flt crew accomplished the emerg checklist, extdd the lndg gear & made an uneventful lndg. An exam of the acft disclosed that the rgt lndg gear retraction fitting had failed & a hydraulic line was severed. Also, the quantity limiting valve(s) were corroded & the respective piston movement was restricted. Subsequently, both hydraulic systems were drain of fluid. An exam of the fitting attachment bolts revealed the top bolt lost torque & the bolt failed in fatigue; the bottom bolts failed in overload. Adnly, the fitting spigot failed due to hydrogen embrittlement; an improved fitting has been produced to correct hydrogen embrittlement problems. The oper conducted a fleet campaign & fnd 13 loose bolts in other 100 series acft. Svrl airworthiness directives were issued to correct the loss of torque on attachment bolts, which included checking the torque at the 300 hr lndg gear inspn.
Aircraft
- Registration
- N922HA
- Reported as
- de Havilland DHC-8-102
- Category
- Airplane
- Serial number
- 094
- Airframe hours
- 9,081
- Engine
- P&W 120A, 2,000 horsepower, turbo prop
- Damage
- Minor damage
- Flight
- Part 121
- Operator
- Henson Airlines
- Registered owner
- Westinghouse Credit Corp
- Airworthiness certificate
- Standard, Transport
- Last inspection
- Continuous airworthiness · July 12, 1991 · 25 hours before
- Departed
- 49J · Hilton Head Isl, SC
- Destination
- JAX · Jacksonville, FL
- Flight plan
- IFR
- Airport
- SAV · Savannah, runway 27, 9,003 × 150 ft, asphalt
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 32
- Certificates
- Commercial, Airline transport, Flight instructor
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Valid Medical--w/ waivers/lim
- Seat
- Left
- Flight hours
- 8,671 total · 2,359 in this make and model · 5,375 as pilot in command · 6 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Dusk
- Wind
- 270° at 6 knots
- Visibility
- 8 statute miles
- Lowest ceiling
- 1,100 ft broken
- Temperature
- 77 °F, dew point 75 °F
- Altimeter
- 29.00 inHg
- Observed at
- SAV, 1 nm away
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.