# NTSB FTW97GA350: Bell OH-58A, N149SD, Newark, TX, September 17, 1997 - Type: NTSB accident investigation - Classification: Accident · Fatal · Final report - Date: September 17, 1997, 09:45 local (14:45 UTC) - Place: Newark, TX - Coordinates: 32.999259, -97.440193 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=32.9993&lon=-97.4402&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 2 fatal - Status: Completed, report March 12, 1999 - Report: Approved by Office Director - NTSB case key (mKey): 20059 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW97GA350 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/20059/pdf - Page: https://openairdocs.org/ntsb/FTW97GA350 ## Probable cause The pilot's failure to maintain adequate rotor rpm which resulted in a loss of aircraft control. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, maneuvering - maneuver - abrupt, pilot in command - adequate rotor rpm - not maintained, pilot in command (cause) - aircraft control - not maintained, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled ## Analysis The helicopter collided with the ground after it descended from level flight in a right rotating turn. According to witnesses, the helicopter landed and tookoff after a few minutes on the ground. The helicopter circled the airport and was headed upwind about 500 feet above the ground when it pitched up, 'hovered for an instant' and descended to the ground. Examination of the helicopter did not disclose evidence of mechanical malfunction. The filament of the low rotor rpm warning light bulb was stretched, which was indicative that it was on at the time of impact. Acoustic analysis of a video tape recording of the accident revealed the rotor rpm during the descent was 80 percent (normal operating range 90-107 percent). According to the helicopter manufacturer, under the given conditions, at a gross weight of 3,250 pounds, and a height of 500 feet, a hover out of ground effect can be accomplished. The estimated gross weight of the helicopter was 2,750 pounds. ## Factual narrative HISTORY OF FLIGHT On September 17, 1997, approximately 0945 central daylight time, a military surplus Bell OH-58A helicopter, N149SD, registered to and operated by the Tarrant County Sheriff's Department (TCSD), was destroyed when it impacted the ground in an uncontrolled descent at Kenneth Copeland Airport near Newark, Texas. The commercial pilot and the observer, who were both employed as peace officers by the TCSD, received fatal injuries. Visual meteorological conditions prevailed, and no flight plan was filed for the public use flight that originated from Fort Worth Meacham International Airport in Fort Worth, Texas, at 0910. The TCSD stated on the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2) that the flight was "a surv[eillance] mission of suspected criminal activity" in the vicinity of Copeland Airport and "apparently the pilot elected to use the runways for either training in the traffic pattern or to wait there until the next pass on the suspected area." Three witnesses, who were in a pickup truck driving to their work site on the west side of Copeland Airport, reported observing the helicopter "sitting idling" or "hovering" at the south end of runway 17-35. They watched the helicopter for a few minutes and then observed it takeoff to the south and turn left. The witnesses then drove north to a tank battery located "about the midpoint of the runway and a couple of hundred feet west of the runway." After getting out of the truck, two of the witnesses again began to watch the helicopter which had circled the airport and was now north of them heading south over the runway. One of the witnesses at the tank battery estimated the helicopter was at an altitude of "about 300 feet" agl when the nose "pitched up vertically" to the point where the "rotor blade was perpendicular to the ground." He stated that the helicopter then rolled from side to side, made two or three "gyrations," leveled off and began rotating around its center axis. He continued to watch the helicopter, which stayed level and descended rapidly, until he lost sight of it behind trees. Another witness at the tank battery stated that "the front end of the helicopter went straight up in the air." He further stated that the nose went down and the tail went up "a couple of times," then the helicopter leveled out and went into a spin. The witness reported that as the helicopter spun, the main rotor blades were "not too blurry," as though they were turning slower than normal. A witness, who was working at a gas well site located on the north side of the airport, reported that the helicopter flew directly over him from north to south. He estimated the helicopter was at an altitude of "500 to 600 feet" agl and stated that it was "going at a pretty good speed". The helicopter traveled "200 to 300 yards" south of his position and "made a 180 degree turn and faced back to the north." He stated that the helicopter "stopped for a second / hovered for an instant," and he heard a "little pop." He further stated that the helicopter then began to rotate and to descend. A witness, who was riding a motorcycle near the intersection of runways 12-30 and 17-35, looked up at the helicopter when he heard the frequency of the sound it was making decrease "rapidly." He observed "the body of the helicopter rotating below the main rotor." He stopped the motorcycle and continued to watch the helicopter, which he estimated to be "about 300 to 400 feet" agl. He stated that the helicopter was spinning and coming straight down with no forward motion. He further stated that he heard the whine of the engine running, but "it seemed to be at low power, as if the helicopter were idling on the ground." The witness observed the helicopter impact the ground and reported that it "hit the ground flat" and bounced. He heard no sound of the engine running after the impact; however, he watched the main rotor continue to turn for about 2 minutes. Witnesses, who were located in the parking lot of the Child Learning Center operated by Kenneth Copeland Ministries, reported having heard and seen the helicopter flying in the vicinity of the airport prior to the accident. They stated that a change in sound coming from the helicopter drew their attention to it, and when they looked up at the helicopter, they saw it spinning and descending straight down. A video, taken by personnel of Kenneth Copeland Ministries, shows the helicopter spinning to the right and descending vertically until it passes out of view behind trees. The video does not show the helicopter entering the spin. PERSONNEL INFORMATION The pilot occupied the right front seat of the helicopter, and the observer occupied the left front seat. Review of FAA and military records revealed no evidence that the observer had received any flight training. According to FAA records, the pilot held a commercial pilot certificate with helicopter and instrument ratings issued on July 13, 1981. At the time of the accident, he held a second class medical certificate issued on March 31, 1997, with no limitations. According to TCSD personnel, the pilot obtained the majority of his helicopter flight training and flight time as an officer in the U.S. Army Reserves. He completed military flight training in 1980 and remained active as a military pilot, flying primarily Bell UH-1H (Huey) military helicopters, for approximately 6 years. In 1994, when the TCSD acquired three military surplus Hughes OH-6 helicopters, the pilot began flying again and accumulated approximately 50 hours flight time in the OH-6. The TCSD traded two of the OH-6 helicopters for two OH-58A helicopters in April 1995. In April 1997, the pilot began flying the TCSD OH-58A helicopters. A request was made by the NTSB investigator-in-charge (IIC) to the Department of Defense (DOD) for information on the pilot's military flight training and experience. According to the DOD, a search of records at the U.S. Army Reserve Personnel Center, St. Louis, Missouri, was unsuccessful in locating a complete military service record for the pilot. Microfiche copies of an incomplete record indicated that the pilot completed the Officer Rotary Wing Aviator Course, Class 80-26, at Fort Rucker, Alabama, on December 17, 1980. No records detailing the pilot's military flight hours were found on the microfiche. Records provided by Bell Helicopter showed that in August 1997, the pilot successfully completed a Bell 206 Transition Course at the Bell Helicopter Customer Training Academy in Fort Worth, Texas. (The Bell 206 is the civilian version of the Bell OH-58.) On the course registration form, the pilot indicated that he had accumulated 2,400 hours of helicopter flight time of which 25 hours were in the last 6 months. He reported that he had flown the following models of helicopters: UH-1H, OH-6, and OH-58. The course flight records indicated that between August 5 and 8, 1997, the pilot received a total of 4.8 hours dual instruction during three flights in Bell 206B helicopters. During a personal interview conducted by the IIC, the pilot's flight instructor for all three flights reported that the pilot was apprehensive when the training began, but at the end of the three sessions was flying "like a 2,000 hour pilot." According to the instructor, the training did not include demonstrations of settling with power or loss of tail rotor effectiveness. An out of ground effect hover and a deceleration from cruise speed to 60 knots and back to cruise speed were demonstrated by the instructor, but not practiced by the pilot. Quick stops (decelerations to a hover) from a speed of 40 knots at an altitude of 30 feet agl were practiced by the pilot during the training. Records provided by the TCSD indicated that the pilot had flown N149SD a total of 8.7 hours prior to the accident flight. The records indicated that the pilot had flown N642SD, t ## Aircraft - Registration: [N149SD](https://openairdocs.org/deregistered/N149SD-2006-08-10), registration cancelled 2006-08-10, S/N 70-15149 (OpenAirDocs) - Reported make and model: Bell OH-58A - Registry model: [Bell OH-58A](https://openairdocs.org/model/bell-oh-58a) (registry code 1181579) (OpenAirDocs) - Category: Helicopter - Serial number: 70-15149 - Airframe hours: 3698 - Engines: Allison T63-A720 420 horsepower turbo shaft - Damage: Destroyed - Flight: Public aircraft, Public use - Registered owner: Tarrant County Sheriff'S Dept. - Departed: FTW, FORT WORTH, TX - Airport: 4TA2, Kenneth Copeland ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; commercial; instrument ratings: helicopter; medical: class 2, valid medical--no waivers/lim.; seat: right; toxicology performed; flight hours: 2,400 total, 25 in this make and model, 22 in the last 90 days, 5 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 190° at 15 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 86 °F, dew point 70 °F - Altimeter: 29.00 inHg - Observed at: AFW, 8 nm away ## 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 19970917027039A](https://openairdocs.org/incident/19970917027039A), Sep 17, 1997: Bell OH58A, Ft Worth, TX, Destroyed, 2 fatal. Observed spinning to ground. Possible lost tail rotor effect. (.19) on September 17, 1997, approximately 0945 central daylight time, a military surplus Bell… 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.