Vanderark RV-10 N917VA

Summary

On 12 November 2017 at about 17:25 local time, a Vanderark RV-10 registered N917VA was involved in an accident near Sun Lakes, Arizona, United States. One person was 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

12 November 2017 at 17:25

Classification

Accident

Location

Sun Lakes, Arizona, United States

Coordinates

33.2428, -111.9264

Aircraft

Vanderark RV-10

Registration

N917VA

Category

Airplane

Year built

2014

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Chandler → Chandler

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR18LA030

Nobody was injured.

The fatigue fractures of the upper and lower alternator attachment bolts, which decreased the common drive belt tension and resulted in the subsequent in-flight separation of an alternator drive belt, the overheating of the engine, and the subsequent total loss of engine power. 

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

Read the full NTSB narrative

The private pilot reported that, during the en route climb, he smelled antifreeze and realized that the engine was overheating. He then reduced power to idle and turned the airplane back toward the departure airport. As the airplane descended, the pilot added power, but the engine did not respond. He decided to land at a nearby closed airport; however, when he realized that the airplane would be unable to reach it, he performed a forced landing to a desert. During the landing roll, the airplane struck several bushes, which resulted in the nosewheel and left main landing gear collapsing and the left wing and fuselage sustaining substantial damage. The airplane was powered by a modified automobile engine, which was equipped with two alternators and a water pump to circulate the engine coolant. The common drive belt that connected the two alternators and water pump was found detached. In addition, the upper and lower attachment bolts that secured one of the alternators were fractured, and the alternator was partially displaced. Examination of the fracture surfaces of both bolts revealed that they exhibited rachet marks, consistent with fatigue fractures. It is likely that, once the alternator attachment bolts fractured, the common drive belt tension decreased, which resulted in the separation of the belt. The belt separation would have precluded the water pump from operating and led to the engine overheating and eventually losing total power.

Quoted verbatim from the NTSB record.