Noorduyn UC-64A N225BL

Summary

On 11 July 2009 at about 21:00 local time, a Noorduyn UC-64A registered N225BL, operated by Renfro Michael W, was involved in an accident near Akiachak, Alaska, United States. 2 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

11 July 2009 at 21:00

Classification

Accident

Location

Akiachak, Alaska, United States

Coordinates

60.9058, -161.4264

Aircraft

Noorduyn UC-64A

Registration

N225BL

Category

Airplane

Engines

1

Operator

Renfro Michael W

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Bethel → Tuluksak

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ANC09LA065

Nobody was injured.

The loss of engine power due to the failure of a crankshaft component, resulting in an off-airport landing.

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

Read the full NTSB narrative

The airline transport pilot was on a Title 14, CFR Part 135 passenger flight. The pilot said during cruise flight he heard a loud bang, and the engine started running rough. He said he diverted to the nearest airport, but the engine quit completely, and he was unable to reach the runway. The airplane subsequently collided with terrain, sustaining substantial damage to both wings and the fuselage. An examination of the engine revealed that a locking screw had backed out of one of the anti-vibration counterweights on the crankshaft, scoring the interior back surface of the engine case. The unsecured counterweight then moved from its position in the crankshaft, and was likely struck by the engine's master rod, which shattered the weight, and liberated it from its normal location. The liberated counterweight was struck by internal moving parts, creating several component failures, and ultimately an engine seizure.

Quoted verbatim from the NTSB record.