Deussen Alexander II Rotorway Exec N5436X accident, Gibson, LA, Nov 5, 2005 · NTSB DFW06CA020

Probable cause

The loss of engine power for undetermined reasons. A contributing factor was the lack of suitable terrain for the forced landing.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of engine power(total) - mech failure/malfApproach

Reason for occurrence undeterminedCause

Forced landingDescent - emergency

In flight collision with objectEmergency landing

Object - tree(s)

Terrain condition - none suitable

Analysis

The 2,000-hour commercial pilot was performing initial hover test flights in a homebuilt helicopter he had recently acquired for parts. The pilot reported that approximately 30-minutes into the first test flight, the liquid cooled engine began to overheat. The pilot added that he elected to land and shut the engine down to investigate. He observed water leaking from a hose clamp on the engine cooling system. He tightened the clamp and waited for the engine to cool down. After checking for leaks, the pilot elected to continue with the test flight. After another 20-minutes of additional hovering, the pilot proceeded to stay in a traffic pattern to perform takeoffs and landings. While in the traffic pattern at his 200 acre ranch, the pilot neglected to monitor the engine instruments and while on the fifth approach, while the helicopter was at about 300 feet agl, the engine lost power. The pilot initiated an autorotation; however the helicopter was unable to clear a tree line, and the main rotor blades collided with a tree. The helicopter impacted the ground hard, coming to rest against a tree. At the time of the accident, the pilot estimated that the winds were from 150 degrees at 10 knots. The reason for the loss of engine power could not be determined.

Factual narrative

The 2,000-hour commercial pilot was performing initial hover test flights in a homebuilt helicopter he had recently acquired for parts. The pilot reported that approximately 30-minutes into the first test flight, the liquid cooled engine began to overheat. The pilot added that he elected to land and shut the engine down to investigate. He observed water leaking from a hose clamp on the engine cooling system. He tightened the clamp and waited for the engine to cool down. After checking for leaks, the pilot elected to continue with the test flight. After another 20-minutes of additional hovering, the pilot proceeded to stay in a traffic pattern to perform takeoffs and landings. While in the traffic pattern at his 200 acres ranch, the pilot neglected to monitor the engine instruments and while on the fifth approach, while the helicopter was at about 300 feet agl, the engine lost power. The pilot initiated an autorotation; however the helicopter was unable to clear a tree line, and the main rotor blades collided with a tree. The helicopter impacted the ground hard, coming to rest against a tree. At the time of the accident, the pilot estimated that the winds were from 150 degrees at 10 knots. The reason for the loss of engine power could not be determined.

Aircraft

Registration: N5436X
Reported as: Deussen Alexander II Rotorway Exec
Category: Helicopter, amateur-built
Serial number: 1
Airframe hours: 58
Engine: Rotorway RW-145, 145 horsepower, reciprocating
Damage: Substantial damage
Flight: Personal · Part 91
Operator: Frankie Gilbert
Registered owner: Frankie Gilbert
Airworthiness certificate: Special, Experimental (Special)
Departed: Gibson, LA

N5436XRegistration cancelled Jul 9, 2013 · Deussen Alexander II ROTORWAY EXECS/N 1 · Built 1984 Airframe modelDeussen Alexander II ROTORWAY EXEC Engine modelRotorway RW-145 seriesReciprocating

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role: Pilot
Age: 64
Injuries: Minor
Certificate: Commercial
Airplane ratings: Single-engine land
Medical: Class 3
Seat: Left
Flight hours: 2,000 total · 1 in this make and model · 2,000 as pilot in command

Weather

Conditions: Visual (VMC) · Day
Wind: 150° at 10 knots
Visibility: 7 statute miles
Lowest ceiling: 10,000 ft broken
Temperature: 79 °F, dew point 70 °F
Altimeter: 29.95 inHg
Observed at: HUM

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.

Accident 20051105031559AAmtr Rotorwayexec · Gibson, LA(-23) Pilot attempted his first flight of his experimental helicopter when he reported that his engine quit running at about 300' AGL. After performing ground checks and hovers, he elected to fly the aircraft when he reported engine coolant temperature rising…Nov 5, 2005 · N5436X · Destroyed