Beechcraft V35 N275BM

Summary

On 18 September 2011 at about 14:35 local time, a Beechcraft V35 registered N275BM, operated by Westchester Flying Club, Inc., was involved in an incident near New Haven, Connecticut, United States. 2 people were on board and nobody was injured. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

18 September 2011 at 14:35

Classification

Incident

Location

New Haven, Connecticut, United States

Nearest airport

Tweed-New Haven (HVN)

Coordinates

41.2636, -72.8889

Aircraft

Beechcraft V35

Registration

N275BM

Category

Airplane

Engines

1

Operator

Westchester Flying Club, Inc.

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

New Haven → Morristown

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

ERA11IA521

Nobody was injured.

The in-flight fatigue failure of the engine’s crankshaft, which resulted in the separation of the forward portion of the crankshaft and the propeller.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

During the climb after takeoff, as the airplane approached 6,000 feet mean sea level, the crankshaft fractured, and the airplane experienced a total loss of engine power. The forward portion of the crankshaft, with the propeller attached, departed the engine. The pilot declared an emergency and returned to the departure airport where he performed a forced landing on a runway. The airplane sustained minor nose gear damage when it overran the runway. Examination of the crankshaft revealed that it was fractured across the No. 4 main journal. Metallurgical examination revealed cracks that initiated on the bearing surface near an oil transfer tube and propagated in fatigue. At the time of the incident, the engine had been operated for about 910 total hours, about 500 hours of which had occurred since maintenance, which was performed about 2 1/2 years before the incident and included the reinstallation of the Nos. 2 and 4 cylinders. The crankcase adjacent to the fractured portion of the crankshaft showed significant fretting on the mating surfaces, possibly due to incorrect torque applied during the previous cylinder repair; however, the investigation could not determine the relevance of that repair, if any, due to the time that had elapsed since the repair was completed.

Quoted verbatim from the NTSB record.