Eurocopter AS350 B3 N970AE

Summary

On 20 January 2004 at about 16:50 local time, a Eurocopter AS350 B3 registered N970AE, operated by Petroleum Helicopters, was involved in an accident near Mesa, Arizona, United States. 3 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

20 January 2004 at 16:50

Classification

Accident

Location

Mesa, Arizona, United States

Nearest airport

Falcon Field (FFZ)

Coordinates

33.4608, -111.7283

Aircraft

Eurocopter AS350 B3

Registration

N970AE

Category

Helicopter

Engines

1

Operator

Petroleum Helicopters

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Phoenix → Falcon Field

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX04CA097

Nobody was injured.

the pilot's excessive flare and mistimed collective application during a practice autorotation, which resulted in a loss of main rotor rpm and a subsequent hard landing. Also causal, was the flight instructor's delayed remedial action and inadequate supervision of the flight. The soft terrain was a factor.

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

Read the full NTSB narrative

The helicopter landed hard and rolled over during a practice autorotation. The purpose of the flight was for the flight instructor to give the flying pilot the recurrent flight checks required by 14 CFR Part 135. They entered a landing pattern parallel to 22R. At 500 feet above ground level (agl) and 80 knots indicated airspeed (IAS), the flight instructor initiated an engine failure. The pilot responded appropriately and entered an autorotation with 60 knots IAS and 398 rpm rotor speed (Nr). At 60 feet agl, the pilot began the flare; however, it was more aggressive than necessary for the conditions. The pilot then lowered the nose after being advised by the flight instructor to do so. At 30 feet agl, the pilot began to increase the collective; the Nr dropped to 380. The flight instructor announced, "I am on the controls with you," and then, "I have the controls." The flight instructor leveled the helicopter and reduced the collective. About 5 feet agl, the flight instructor initiated the final collective application. As the Nr decreased, the tail rotor lost effectiveness; the helicopter yawed to the left with full right anti-torque pedal applied. The helicopter touched down and the nose was approximately 15 degrees to the left of the direction of travel. The right skid touched down and the helicopter drifted to the right. The helicopter then rolled to the right despite corrective inputs by the flight instructor. The front portion of the right skid dug into the soft turf and pivoted the helicopter forward and the main rotor blades contacted the ground. No mechanical malfunctions were reported.

Quoted verbatim from the NTSB record.