MD Helicopters 369A N369HW

Summary

On 2 April 2013 at about 17:00 local time, a MD Helicopters 369A registered N369HW was involved in an accident near Darby, Montana, United States. 4 people were on board and one was seriously injured, 3 had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

2 April 2013 at 17:00

Classification

Accident

Location

Darby, Montana, United States

Nearest airport

Private Property (NONE)

Coordinates

45.9325, -114.1206

Aircraft

MD Helicopters 369A

Registration

N369HW

Category

Helicopter

Year built

1970

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Darby → Darby

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR13LA178

1 person was seriously injured.

The pilot's failure to arrest the landing descent due to his incorrect use of the throttle, which resulted in a hard landing.

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

Read the full NTSB narrative

The pilot reported that he purchased the turbine-powered helicopter about 5 weeks before the accident and departed from his private airstrip for a brief local personal flight. During the approach for landing, when the helicopter was about 200 to 300 ft above ground level (agl), he added some power, and the engine responded normally. Shortly thereafter, he conducted a height-velocity check with satisfactory results. The pilot then slowed the helicopter to a descending hover with the engine running at an unspecified speed above flight idle. The pilot stated that, when the helicopter was about 10 ft agl, he increased the throttle setting, but the engine did not respond. He added collective to slow the descent, but the helicopter landed hard. Postaccident on-scene examination and system testing did not reveal evidence of any mechanical anomalies that would have resulted in a loss of engine power. The engine was tested in its as-removed condition and satisfactorily met all operational test and power calibration criteria with no anomalies or deficiencies noted. Review of the helicopter manufacturer's operating manual revealed that, during all phases of normal flight, the throttle should be in the full open (normal) position and should not be moved by the pilot. With the throttle in the full open position, a governor automatically increases and decreases engine power to maintain rotor rpm as the pilot raises and lowers the collective. According to the manufacturer, when the throttle is not in the full open position, the governor will not maintain rotor rpm, and full power will not be available. The pilot's statement that he increased the throttle setting about 10 feet agl indicates that he was manipulating the throttle contrary to the operating manual procedures, and this is likely the reason he was unsuccessful in stopping the helicopter's descent.

Quoted verbatim from the NTSB record.