Schweizer 269C N2096W

Summary

On 2 July 2015 at about 05:15 local time, a Schweizer 269C registered N2096W, operated by Precision Aviation Training, LLC, was involved in an accident near Newberg, Oregon, United States. 2 people were on board and 2 died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

2 July 2015 at 05:15

Classification

Accident

Location

Newberg, Oregon, United States

Nearest airport

Chehalem Airpark (17S)

Coordinates

45.3292, -123.0697

Aircraft

Schweizer 269C

Registration

N2096W

Category

Helicopter

Year built

2004

Engines

1

Operator

Precision Aviation Training, LLC

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Newberg → Newberg

Aircraft damage

Destroyed

Weather

VMC

Light

Night

NTSB number

WPR15FA205

2 people died.

The loss of translation/rotational power between the engine and the transmission due to the severe wear of the forward spline portion of the lower coupling drive shaft. The reason for the severe wear of the forward spline could not be definitively determined due to fire damage and the loss of associated components, which were not located during the investigation.

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

Read the full NTSB narrative

The instructor and student were conducting a night orientation flight. According to a witnesses who worked for the operator, about 15 minutes after the helicopter departed, he heard what sounded like an engine rollback and the helicopter making an autorotation. This was followed by the sound of an increase in engine rpm and the drive belts squealing, culminating with the sound of the helicopter making a loud thud-type noise. Another witness stated that the engine sounded rough and that the helicopter was making a high pitch whining/squealing sound, after which it went silent. A third witness also heard the helicopter making high pitch noise just before the accident. The helicopter was subsequently located in an open field near the departure airport; a postcrash fire erupted, which consumed the helicopter. A postaccident examination of the lower coupling drive shaft showed evidence of severe wear completely around the forward spline that extended beyond the root of the spline teeth. Severe wear of the forward spline teeth could have been caused by a loss of alignment between the engine and the drive shaft or an inflight loss of lubrication in the rubber boot. The rubber boot that retains grease for the forward spline portion of the drive shaft was not recovered and was presumed missing. Loss of grease coverage for the forward spline, either from a rupture of the rubber boot or a loss of the clamp for the rubber boot, could cause sudden inflight wear and overheating of the spline teeth. Severe wear of the forward spline portion of the lower coupling drive shaft most likely led to sudden and complete loss of translational/rotational power between the engine and the transmission. The reason for the severe wear of the forward spline could not be definitively determined due to fire damage and the loss of associated components, which were not located during the investigation.

Quoted verbatim from the NTSB record.