- Date
- April 8, 2000, 08:30 local (14:30 UTC)
- Place
- Englewood, CO
- Injuries
- 3 uninjured
- Damage
- Minor damage
- Phase of flight
- Initial climb
- Aircraft
- N928PTBeech A60
- Weather
- Visual (VMC) · Day
- Status
- Completed · report April 6, 2001
- Report
- Approved by Office Director
- Case key
- 49021
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 failure of a number one cylinder connecting rod bolt due to under-torquing during engine major overhaul.
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
On departure, the left engine of the twin-engine airplane failed. Postincident examination of the left engine revealed a six-inch hole in the case, and that two connecting rod bolts on the number one cylinder had separated. Examination indicated that one of the rod bolt failed due to fatigue. An SEM examination of the outside surface adjacent to the fracture face revealed no indication of a manufacturing anomaly. Fretting damage was found on the arm of the connecting rod that was associated with this bolt. The physical evidence suggested that the bolt was improperly torqued. Maintenance records indicate that the left engine received a major overhaul 2.5 hours before the incident. A representative of the engine manufacturer said that the rod bolts on this engine are properly installed when the tightening of the nut stretches the bolt to a specified dimension.
Factual narrative
On April 8, 2000, approximately 0830 mountain daylight time, a Beech A60, N928PT, received minor damage following an engine failure during initial climb after takeoff from Centennial Airport, Englewood, Colorado. The flight instructor, the private pilot receiving instruction, and a passenger were not injured. The airplane was being operated by the private pilot under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the cross-country instructional flight that originated approximately 15 minutes before the incident. An instrument flight plan had been filed.
The flight instructor said that while on departure from Centennial Airport, the left engine failed. He said that they returned to the airport and landed without incident. Postincident examination of the left engine revealed a six-inch hole in the case, and that two rod bolts on the number one cylinder connecting rod had separated.
Examination by a National Transportation Safety Board's (NTSB) Materials Laboratory engineer indicated that one of the rod bolts separated due to a fatigue failure. An SEM examination of the outside surface adjacent to the fracture face revealed no indication of a manufacturing anomaly. Fretting damage was found on the arm of the connecting rod that was associated with this bolt.
Maintenance records indicate that the left engine received a major overhaul 2.5 hours before the incident. A representative of the engine manufacturer said that the rod bolts on this engine are properly installed when the tightening of the nut stretches the bolt to a specified dimension.
Aircraft
- Registration
- N928PT
- Reported as
- Beech A60
- Category
- Airplane
- Serial number
- P-174
- Engine
- Lycoming TIO-541, 385 horsepower, reciprocating
- Damage
- Minor damage
- Flight
- Instructional · Part 91
- Registered owner
- Raulf D. Janitell, III
- Airworthiness certificate
- Standard, Normal
- Departed
- APA
- Destination
- SDL · Scottsdale, AZ
- Flight plan
- IFR
- Airport
- APA · Centennial Airport
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
- 40
- Certificates
- Flight instructor, Commercial
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Right
- Flight hours
- 3,123 total · 210 in this make and model · 2,983 as pilot in command · 125 in the last 90 days · 35 in the last 30 days · 1 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 280° at 6 knots
- Visibility
- 20 statute miles
- Lowest ceiling
- None
- Temperature
- 70 °F, dew point 36 °F
- Altimeter
- 30.00 inHg