Robinson R44 N921ES

Summary

On 28 May 2016 at about 21:35 local time, a Robinson R44 registered N921ES, operated by Flying Helicopters Inc, was involved in an accident near Spring Branch, Texas, 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

28 May 2016 at 21:35

Classification

Accident

Location

Spring Branch, Texas, United States

Nearest airport

Kestrel Airpark (1T7)

Coordinates

29.5025, -98.2439

Aircraft

Robinson R44

Registration

N921ES

Category

Helicopter

Year built

2014

Engines

1

Operator

Flying Helicopters Inc

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Borne → Spring Branch

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

GAA16CA283

Nobody was injured.

The pilot's failure to maintain helicopter control while hovering in gusting tailwind conditions, resulting in the tailboom striking a light pole and impact with terrain.

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

Read the full NTSB narrative

According to the pilot, he was hover taxiing the helicopter in a confined area, after refueling. He reported there was a large tree to the southwest of his position and a light pole to northeast of his position. He recalled that he began to taxi to the northwest; away from the light pole, but "a significant left quartering wind" about 9 knots gave him "a hard time controlling the tail". He reported that he did not feel that he could turn the nose into the wind in the confined area and decided to climb vertically to avoid obstacles. He reported that he ascended, encountered a wind gust, and the tailboom yawed to the right and struck the light pole. The helicopter descended, impacted the ground, and came to rest on its left side. The helicopter sustained substantial damage to the fuselage, the main and tail rotor systems. The pilot reported that there were not any mechanical anomalies or malfunctions with any portion of the helicopter that would have prevented normal flight operations. The nearest weather reporting station was two miles north-northwest. The meteorological aerodrome report about the time of the accident reported the wind was out of 160 degrees true at 11 knots. FAA-8083-21A, Chap. 11-20 para. 2 states: Weathercock Stability (120–240°) In this region, the helicopter attempts to weathervane, or weathercock, its nose into the relative wind. Unless a resisting pedal input is made, the helicopter starts a slow, uncommanded turn either to the right or left, depending upon the wind direction. If the pilot allows a right yaw rate to develop and the tail of the helicopter moves into this region, the yaw rate can accelerate rapidly. In order to avoid the onset of LTE in this downwind condition, it is imperative to maintain positive control of the yaw rate and devote full attention to flying the helicopter.

Quoted verbatim from the NTSB record.