N716JB

Substantial
Serious

GRAY ROTORWAY EXEC S/N: EXEC-3000

Accident Details

Date
Friday, October 1, 1999
NTSB Number
DEN00LA001
Location
GALLUP, NM
Event ID
20001212X19938
Coordinates
35.519203, -108.730682
Aircraft Damage
Substantial
Highest Injury
Serious
Fatalities
0
Serious Injuries
1
Minor Injuries
0
Uninjured
0
Total Aboard
1

Probable Cause and Findings

The pilot inadvertently allowing main rotor rpm to decay while avoiding obstacles during an emergency autorotation following a loss of power for reasons undetermined. Factors were houses and powerlines.

Aircraft Information

Registration
Make
GRAY
Serial Number
EXEC-3000
Engine Type
Reciprocating
Model / ICAO
ROTORWAY EXEC BPAT
Aircraft Type
Rotorcraft
No. of Engines
1
Seats
2
FAA Model
EXEC

Registered Owner (Current)

Name
GRAY JIM R
Address
1315 N LIBERTY ST APT 1534
City
BOISE
State / Zip Code
ID 83704-0106
Country
United States

Analysis

On October 1, 1999, approximately 0645 mountain daylight time, a Gray Rotorway Executive homebuilt helicopter, N716JB, registered to and operated by the pilot, was destroyed when it collided with terrain during descent at Gallup, New Mexico. The solo student pilot was seriously injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the instructional flight being conducted under Title 14 CFR Part 91. The flight originated at Gallup, New Mexico, approximately 0630.

In his accident report, the pilot said he intended on remaining in the traffic pattern to practice touch and go landings. He had purposely planned the early morning flight because the "wind is usually calm and density altitude is lowest, giving the helicopter best performance capabilities." The flight was uneventful until the helicopter reached the point where the pilot would turn from downwind to base leg, and he noticed the "rotor rpm was low (95%)." He turned the helicopter towards the runway and "lowered collective [to] stabilize rotor rpm." At this point, "the engine failed." He "lowered collective [control] all the way down, [pushed] the cyclic [control] forward, and began autorotation." The helicopter descended toward houses, so he "extended [the descent path] by pulling collective." Rotor rpm fell to 80%. The pilot headed towards a small open field but as he descended to 100 feet agl (above ground level), he noticed powerlines ahead. He did a "second extension," and power dropped to 60%. Approximately 30 feet agl, he pulled the nose up and added full up collective to arrest the descent. The helicopter struck the ground tail first, then rolled over on its left side.

In December 1999, the engine was functionally tested at the facilities of Rotorway in Chandler, Arizona. Despite impact damage to the crankshaft, the engine operated normally.

Data Source

Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# DEN00LA001