# NTSB SEA97LA158: Bell 47G-3B-1, N8537F, Roosevelt, UT, July 5, 1997 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: July 5, 1997, 13:00 local (19:00 UTC) - Place: Roosevelt, UT - Coordinates: 40.280567, -109.999076 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.2806&lon=-109.9991&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 2 uninjured - Status: Completed, report April 24, 1998 - Report: Approved by Office Director - NTSB case key (mKey): 42647 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA97LA158 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42647/pdf - Page: https://openairdocs.org/ntsb/SEA97LA158 ## Probable cause the pilot's failure to maintain directional control. Wind gusts were a factor. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, landing - weather condition - gusts (contributing factor) - directional control - not maintained, pilot in command (cause) - Hard landing, descent - uncontrolled ## Analysis The pilot reported that he was returning to his residence to land on the landing pad. The helicopter was approaching the pad from the north, and at approximately 15 to 25 feet above ground level, when a gust of wind struck the helicopter. When it began to spin to the right, the pilot pulled up to abort the landing and to increase altitude above the nearby tree line. The helicopter continued to spin and move to the west over the tree line, wires, and fences. The pilot opted to land the helicopter in an open field as it continued to spin. The helicopter landed hard, bounced, and then landed again. ## Factual narrative On July 5, 1997, at 1300 mountain daylight time, a Bell 47G-3B-1, N8537F, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, collided with the terrain while attempting to land on a pad at the pilot's residence near Roosevelt, Utah. Visual meteorological conditions prevailed at the time and no flight plan was filed. The helicopter was substantially damaged. The private pilot was seriously injured and his two passengers were not injured. The flight had taken off from Roosevelt about 45 minutes prior to the accident. The pilot reported during an interview and subsequent written statement, that he had taken off from his residence and flew to the Roosevelt Airport for fuel. The helicopter then took off and flew around the area. The pilot stated that he then returned to his residence and was approaching the landing pad from the north. The pilot stated that when the helicopter was about 15 to 25 feet above ground level, a gust of wind struck the helicopter and he pulled up to abort the landing. The helicopter began to spin to the right as he increased altitude to above the tree line. The helicopter continued to spin and move to the west over the tree line, wires and fences. The pilot opted to land the helicopter in an open field as it continued to spin. The helicopter landed hard, bounced and then landed again. The pilot reported that there were no mechanical failures or malfunctions with the helicopter at the time of the accident. Witnesses reported that the wind was from the west at five to 10 knots, with gusts to 15 knots. During the on-site investigation, the investigative team consisting of an inspector from the Slat Lake City, Federal Aviation Administration Flight Standards District Office, Salt Lake City, Utah, and an Air Safety Investigator from Bell Helicopters, Fort Worth, Texas, found evidence that the helicopter initially impacted the ground just west of a fence line running generally north/south. The tailboom contacted the fence line and pushed the top wires down. White paint transfer was noted on the wire. Two marks from the landing skids were noted on the ground. The helicopter became airborne again and subsequently collided with the ground upright about 20 to 30 feet further west of the fence line. Inspection of the wreckage found that the landing skids had collapsed and the helicopter was laying on its belly. The tailboom was bent downward and the aft end of the tailboom was partially buried in the ground. One entire tail-rotor blade remained attached. The blade was bent aft at approximately mid-range. The inboard section of the other tail rotor blade remained attached. The outboard section separated at approximately mid-range and was found about 75 feet forward and to the right of the main wreckage. The tail-rotor driveshaft was bent and separated in several locations. The separated ends displayed evidence of twisting signatures. Control continuity was established throughout the system with no pre-impact anomalies noted. The main rotor blades were bent downwards and had made contact with the ground. One of the two passengers on board reported that there were no unusual noises or vibrations until after the first ground impact. After the first impact, the helicopter bounced and spun, he thought to the right, before it collided with the ground the second time. The passenger stated that the engine was still running after the helicopter came to rest. He stated that he then turned off two switches and the engine stopped. The second passenger stated that the noise and vibration of the helicopter was the same as when he had flown in the helicopter before. The passenger stated that when the helicopter was on final approach at about 15 feet, he felt a "surge of power." The helicopter went up to about 60 feet and was spinning to the right. The helicopter then stopped spinning, came down, and bounced twice. The passenger stated that he remembered that the main rotor blades struck the ground. The engine was still running after the helicopter came to rest. The engine stopped when the two switches with "red guards" were turned off. ## Aircraft - Registration: [N8537F](https://openairdocs.org/deregistered/N8537F-2014-11-24), registration cancelled 2014-11-24, S/N 3390, built 1965 (OpenAirDocs) - Reported make and model: Bell 47G-3B-1 - Registry model: [Bell 47G-3B-1](https://openairdocs.org/model/bell-47g-3b-1) (registry code 1181028) (OpenAirDocs) - Registry engine: [Lycoming TVO-435-GIA](https://openairdocs.org/engine/lycoming-tvo-435-gia) (registry code 41526, turbo-prop) (OpenAirDocs) - Category: Helicopter - Serial number: 3390 - Engines: Lycoming TVO-435 270 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Max L. Ross - Airworthiness certificate: Standard, Normal - Departed: 74V, UT - Destination: UT ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; private; airplane ratings: single-engine land, multi-engine land; medical: class 3, expired; seat: left; flight hours: 850 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 270° at 10 knots, gusting 15 - Visibility: 50 statute miles - Lowest ceiling: none - Temperature: 75 °F ## 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 19970705017029A](https://openairdocs.org/incident/19970705017029A), Jul 5, 1997: Bell 47G3B1, Roosevelt, UT, Substantial damage. Trying to land at private helipad. Wind gust hit copter. Pilot pulled up. Entered loss tailrotor effectiveness. ## Other investigations on N8537F (5) 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 DEN80DTM01](https://openairdocs.org/ntsb/DEN80DTM01), Oct 1, 1979: Bell 47G3B1 (N8537F), Torrey, UT, substantial damage - [NTSB SEA69A0008](https://openairdocs.org/ntsb/SEA69A0008), Jul 23, 1968: Bell 47G3B1 (N8537F), North Fork, ID, destroyed, 1 fatal - [NTSB DEN67A0052](https://openairdocs.org/ntsb/DEN67A0052), Mar 10, 1967: Bell 47G3B1 (N8537F), Cody, WY, destroyed - [NTSB DEN67A0048](https://openairdocs.org/ntsb/DEN67A0048), Feb 21, 1967: Bell 47G3B1 (N8537F), Riverton, WY, substantial damage - [NTSB DEN66A0025](https://openairdocs.org/ntsb/DEN66A0025), Oct 5, 1965: Bell 47G3B1 (N8537F), Salt Lake City, UT, destroyed 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.