# NTSB DEN00LA001: Gray Rotorway Exec, N716JB, Gallup, NM, October 1, 1999 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: October 1, 1999, 06:45 local (12:45 UTC) - Place: Gallup, NM - Coordinates: 35.519203, -108.730682 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.5192&lon=-108.7307&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report June 21, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 47524 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN00LA001 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/47524/pdf - Page: https://openairdocs.org/ntsb/DEN00LA001 ## Probable cause 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. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, approach - vfr pattern - base turn - autorotation - performed, pilot in command - reason for occurrence undetermined - Forced landing, descent - emergency - object - residence - rotor rpm - not maintained, pilot in command - object - wire,transmission - In flight collision with terrain/water, descent - emergency ## Analysis The pilot remained in the traffic pattern to practice touch and go landings. At approximately the point where the helicopter would turn onto the base leg, rotor rpm began to decay (95%). The pilot turned towards the runway and began autorotation. During the descent, the pilot managed to avoid houses and powerlines. The helicopter struck the ground tail first, then rolled over on its left side. The engine was later functionally tested and, despite impact damage to the crankshaft, operated normally. ## Factual narrative 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. ## Aircraft - Registration: [N716JB](https://openairdocs.org/aircraft/N716JB), registered now, S/N EXEC-3000 (OpenAirDocs) - Reported make and model: GRAY ROTORWAY EXEC (ROTORWAY E) - Registry model: [Gray Jim Robert EXEC](https://openairdocs.org/model/gray-jim-robert-exec) (registry code 13017FT) (OpenAirDocs) - Registry engine: [Rotorway RW-145 series](https://openairdocs.org/engine/rotorway-rw-145-series) (registry code 55005, reciprocating) (OpenAirDocs) - Category: Helicopter, amateur-built - Serial number: EXEC-3000 - Airframe hours: 140 - Engines: Rotorway RW-152 152 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Jim R. Gray - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, September 18, 1999, 10 hours before - Departed: GUP, NM - Airport: GUP, Gallup Municipal, runway 24, 7,312 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; student; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 158 total, 155 in this make and model, 127 as pilot in command, 14 in the last 90 days, 5 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Dawn - Wind: calm - Visibility: 15 statute miles - Lowest ceiling: none - Temperature: 30 °F, dew point 28 °F - Altimeter: 30.00 inHg - Observed at: GUP ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19991001040219A](https://openairdocs.org/incident/19991001040219A), Oct 1, 1999: Amtr ROTORWAYEXEC, Gallup, NM, Substantial damage. (.4) The pilot remained in the traffic pattern to practice touch and go landings. At approximately the point where the helicopter would turn onto the base leg,… ## Other investigations on N716JB (3) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB WPR18LA050](https://openairdocs.org/ntsb/WPR18LA050), Dec 17, 2017: Gray Jim Robert Exec (N716JB), Caldwell, ID, substantial damage. Probable cause: Failure of the oil pressure gauge line, which resulted in oil exhaustion and a total loss of engine power. - [NTSB WPR17LA009](https://openairdocs.org/ntsb/WPR17LA009), Oct 19, 2016: Gray Jim Robert Exec 90 (N716JB), Caldwell, ID, substantial damage. Probable cause: The pilot's failure to properly tighten the tension bolts during the installation of the alternator belt, which resulted in inadequate voltage to sustain ignition and the subsequent partial loss of… - [NTSB FTW02LA250](https://openairdocs.org/ntsb/FTW02LA250), Sep 5, 2002: Gray Rotorway Exec 90 (N716JB), Las Cruces, NM, substantial damage. Probable cause: The pilot's failure to refuel the helicopter, which resulted in fuel exhaustion. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.