Hughes 269C N9575F

Summary

On 14 November 1988 at about 17:17 local time, a Hughes 269C registered N9575F was involved in an accident near Mohawk, Tennessee, United States. 2 people were on board and 2 died. The aircraft was destroyed. No probable cause statement is available for this record.

Date

14 November 1988 at 17:17

Classification

Accident

Location

Mohawk, Tennessee, United States

Nearest airport

Cooper Field (PVT)

Coordinates

36.1808, -83.1194

Aircraft

Hughes 269C

Registration

N9575F

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Morristown → Unknown

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

ATL89FA035

2 people died.

The NTSB has not published a probable cause for this record. No probable cause statement is present in the source data.

Nothing about the cause is stated here that is not in the source record.

Read the full NTSB narrative

THE HELICOPTER HAD LANDED AT A PRIVATE AIRSTRIP AND THE INSTRUCTOR DEPLANED. THE DUAL STUDENT REMAINED IN THE HELICOPTER WITH THE ENGINE RUNNING. THE CFI REBOARDED AND THE STUDENT MADE THE TAKEOFF. LATER, ON DOWNWIND IN TRAFFIC PATTERN, A WITNESS REPORTED A LOUD NOISE FROM THE ENGINE. THE MAIN ROTOR WAS OBSERVED TO SLOW NOTICEABLY AND THE HELICOPTER ENTERED A VERY STEEP DESCENT, IMPACTING THE GROUND ABOUT 1,000 FEET SOUTH OF THE RUNWAY. THE ENGINE ROD BOLTS ON THE NUMBER FOUR CYLINDER HAD FRACTURED. EXAMINATION OF THE FLIGHT CONTROLS REVEALED NO EVIDENCE OF PREIMPACT FAILURE. ONE OF THE ROD BOLTS WAS METALLURGICALLY EXAMINED AND SHOWED CRACKING THROUGH 25 PERCENT OF THE BOLT. THE FATIGUE WAS ATTRIBUTED TO INSUFFICIENT PRELOAD ON THE BOLT. THE ENGINE HAD 813 HRS SINCE A MAJOR OVERHAUL AND 36 HRS SINCE ANNUAL INSPECTION.

Quoted verbatim from the NTSB record.