Hiller OH 23B N6057

Summary

On 24 November 2014 at about 16:30 local time, a Hiller OH 23B registered N6057, operated by Vertically Challenged LLC, was involved in an accident near Leesburg, Virginia, 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

24 November 2014 at 16:30

Classification

Accident

Location

Leesburg, Virginia, United States

Nearest airport

Leesburg Executive (JYO)

Coordinates

39.0781, -77.5575

Aircraft

Hiller OH 23B

Registration

N6057

Category

Helicopter

Year built

1954

Engines

1

Operator

Vertically Challenged LLC

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Leesburg → Leesburg

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ERA15CA059

Nobody was injured.

A loss of tail rotor effectiveness while hovering in gusting crosswind conditions resulting in the student pilot's loss of control of the helicopter. Contributing was the delayed remedial action of the flight instructor.

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

Read the full NTSB narrative

Following an uneventful preflight inspection of the helicopter, the flight instructor and the student pilot boarded the helicopter for a local instructional flight. About 10 seconds after the student pilot lifted the helicopter into a stable hover with a left crosswind, the helicopter began a slow yaw to the right that the student was unable to arrest through the application of the left anti-torque pedal. As the rate of the yaw increased, the flight instructor took control of the helicopter and attempted to stop the yaw with the application of additional left anti-torque pedal, to no avail. The flight instructor then reduced engine power, arresting the yaw, and performed an autorotation to the ground after an estimated 1 3/4 total revolutions. As the helicopter touched down, it rocked backwards, and the tail rotor struck the helicopter's ground handling dolly, resulting in substantial damage to the tail rotor. The flight instructor did not report any pre-impact mechanical malfunctions or failures of the helicopter. Archived weather data showed that wind velocity about the time of the accident was 15 knots, with gusts to 24 knots. According to Federal Aviation Administration Advisory Circular 90-95, pilots are advised to be aware that, "…if a considerable amount of left pedal is being maintained, a sufficient amount of left pedal may not be available to  counteract an unanticipated right yaw." Additionally, pilots should, "Stay vigilant to power and wind conditions."

Quoted verbatim from the NTSB record.