Bellanca 7ECA N53874

Summary

On 25 March 2007 at about 13:30 local time, a Bellanca 7ECA registered N53874 was involved in an accident near Wawayanda, New York, United States. 2 people were on board and 2 had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

25 March 2007 at 13:30

Classification

Accident

Location

Wawayanda, New York, United States

Nearest airport

Sussex (FWN)

Coordinates

41.3306, -74.4781

Aircraft

Bellanca 7ECA

Registration

N53874

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Sussex → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

NYC07LA086

2 people had minor injuries.

A failure of the crankshaft idler gear, which resulted in a total loss of engine power while maneuvering.

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

Read the full NTSB narrative

The flight instructor and student pilot were practicing stalls when the airplane experienced a sudden, total loss of engine power. Postaccident examination of the engine revealed that the left crankcase half idler gear shaft was dislodged from its respective mounting boss. The two idler gear shaft retaining bolts were broken. The idler gear that interconnected the crankshaft and camshaft remained on the idler shaft and was observed with a "U"-shaped fracture at the gear ring area that separated two full teeth. Optical examination of the gear fracture revealed fracture face markings, including arrest lines consistent of fatigue progression, which was estimated to cover more than 95 percent of the fracture surface. Both gear shaft retaining bolts were separated near their respective heads. The bolts displayed severe circumferential wear through the threaded shanks that removed the majority of the bolt diameters. High magnification viewing of the fractures in these areas on both bolts revealed features indicative of multiple origin fatigue propagating through the remaining cross sections. The lock plate was fractured in several locations and heavily distorted. The bolt holes in the lock plate were severely elongated and enlarged over their original diameter. While it was likely that loosening of the bolts precipitated the gear failure, no conclusive evidence was uncovered to confirm that scenario. The engine's most recent annual inspection was performed about 4 months prior to the accident. At that time, the engine had been operated for 1,226 hours since it was overhauled in 1985, and 639 hours since it was disassembled and reassembled after a propeller strike during 2001.

Quoted verbatim from the NTSB record.