Accident I nvest ig at ion

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1 ~ ~ SIN ~~ ~ Report ~ Rolls-Royce ~ - _. Accident I nvest ig at ion Rolls Royce Allison Engine Model 250-CZOB CAE (1) SIN CAE (2) Eurocopter Model BO 105 CBSS Registration N335T Temsco He1 ico p te rs Amarillo, Texas Completed By: s4 John J. Swift Accident Investigator Accident date: March I O, 2000 Report date: March 30,2000

2 SIN CAE (1) I CAE (2) --- March I O, 2000, Temsco Helicopters Inc. TABLE OF CONTENTS 1. SYNOPSIS. 2. FACTUAL INFORMATION History of Flight Personnel Information Injuries to Persons Aircraft Information Meteorological Conditions Aids to Navigation Communications Accident Site Information Flight Recorder Wreckage and Impact Information Engine Examination Engine Maintenance and Records Additional Information 3. SUMMARY OF FINDINGS. 4. APPEND1 C ES. A. Photographs B. Engine Log Book Extract C. Accident Site Map D. Investigation Participants E. Component Tracking Sheets

3 SIN CAE (1) I CAE (2) --- March I O, 2000, Temsco Helicopters Inc. 1. SYNOPSIS During a night medical flight for the purpose of patient transfer, a Eurocopter Model BO 105 CBSS, with two Allison Model 250-C20B engines installed, was involved in an accident in Dallam County, Texas. There was a post crash fire. The aircraft was owned by General Electric Capital Corporation and operated by Temsco Helicopters Incorporated under contract to Northwest Texas Healthcare System. It was totally destroyed as a result of both impact forces and fire. All occupants sustained fatal injuries. The NTSB (National Transportation Safety Board) requested assistance from both the airframe and engine manufacturers. This is a report of the facts and circumstances associated with the accident. 2. FACTUAL INFORMATION 2.1 History of Flight. The Lifestar helicopter was based at the Northwest Texas Healthcare System Hospital in Amarillo. Texas. The crew. consisting of the pilot and two flight paramedics. was assigned to the patient transfer mission at 3:54 AM. The aircraft departed the hospital emergency heliport at 355 AM enroute to Boise City. Oklahoma. The pilot estimated his time enroute to the Boise City hospital to be 40 minutes. At 04:46 AM. 5 1 minutes after takeoff. the pilot reported he would be unable to continue to Boise City because of weather conditions in the area. He said he would be able to land 10 miles south on Highway 385 and requested that the ambulance meet him there for the patient transfer. At 5:OO AM. the pilot reported he was encountering fog. At 5:06 AM (1 hour and 10 minutes after takeoff). the pilot reported he had landed approximately 14 to 15 miles south of Boise City due to weather. At 5:54 AM. the ambulance crew arrived with the patient and transfer was completed. At approximately 6:OO AM. the aircraft departed the site. The pilot told the ground ambulance crew that he intended to fly east of Highway 385 on a southerly heading. The Boise sheriff and his wife, who were driving north on Highway 385, saw the aircraft with all of its lights on flying east of the road and heading south at approximately.8 of a mile south of the transfer point. He did not report that he observed the aircraft make any turns. but he did say it was flying very low. The position that he reported seeing the aircraft was approximately.75 miles due east of where the aircraft had crashed. At approximately 06:40 AM the aircraft was reported overdue and the appropriate authorities were notified. The search was concentrated in an area east of Highway 385. Searchers reported fog and ice fog and indicated their vehicle antennas were icing over. The aircraft was not found until after 09:30 AM because the search effort was hampered by fog. The aircraft wreckage was finally located approximately.8 of a mile south of the transfer point and approximately.5 of a mile west of the road. 2.2 Personnel Information. The pilot held a commercial certificate with fixed wing. rotorcraft, instrument, and flight instructor ratings. The date of issue was 22 December He had logged approximately 3900 hours of flight time. The pilot's 2"d Class medical certificate was current and reflected a renewal date 11 February He had logged approximately 100 hours total time in the B0105CBS5.

4 SIN CAE (1) I CAE (2) --- March I O, 2000, Ternsco Helicopters Inc. 2.3 Injuries to Persons. The pilot, two medical crewmembers, and the passenger (patient) sustained fatal injuries. 2.4 Aircraft Information. Manufacturer Model Serial Number Registration Number Airframe Total Time Last Annual Inspection Last 300 hour Inspection Last 100 hour Inspection Last 50 hour Inspection Eurocopter BO 105 CBS5 S898 N335T Jan 00 at Hours 16 Jan 00 at Hours 20 Nov 99 at Hours 24 Feb 00 at Hours 2.5 Meteorological Conditions. Weather conditions at the time of the accident were based on reports from the ambulance crew. local citizens. sheriffs deputies, and searchers. They all agreed that the visibility was limited due to fog and ice fog. They indicated that ice had accumulated on vehicle surfaces when they were driving. At 6:50 am, The Dalhart observation was a wind from 330 degrees at 8 knots. visibility 15 statute miles. scattered clouds at 1500 feet. and a temperature-de\v point spread of 1 degree centigrade. At 7:50 AM, the observation was a wind from 360 degrees at 10 knots. 1 statute visibility. a broken cloud layer at 200 feet, overcast cloud layer at 1500 feet. and a temperature-dew point spread of 1 degree centigrade. 2.6 Aids to Navigation. Not applicable. 2.7 Communications. Not applicable. 2.8 Accident Site Information. The accident site was located approximately 29 miles north of Dalhart. Texas and approximately 16 miles south of Boise City, Oklahoma. Highway 358 connecting Dalhart and Boise was approximately.5 mile west of the site. The area was flat and predominantly grass prairie. There were no obstructions within a half mile of the accident site. A large area of prairie grass around the wreckage was burned. Wreckage was found both within and outside the burned area. An accident site map is in Appendix C. 2.9 Flight Recorder. The aircraft was not equipped with either a flight data or cockpit voice recorder Wreckage and Impact Information. The aircraft impacted the ground in a nose down, left roll attitude. At the initial impact point, there were ground scars made by the skids, the front of the aircraft, and main rotor blades. A portion of one skid shoe and the outboard part of a main rotor blade were deeply implanted in the ground in this area. The main fuel tank was compromised at impact as evidenced by the large fuel spill at the initial impact point. The aircraft proceeded to tumble, roll, and slide for approximately 242 feet on a general heading of 240 degrees. The tail rotor pylon was separated from the tailboom and the

5 SIN CAE (1) I CAE (2) --- March 10, 2000, Temsco Helicopters Inc. tailboom was separated from the fuselage. Neither showed evidence of fire damage. As the aircraft proceeded along the wreckage path. the contents were scattered along the same path. The largest remaining portion, the engine and main transmission deck, was resting on its right side at approximately 240 feet from the initial impact point. The burn area, some wreckage and the remains of some occupants were found out to approximately 272 feet from the initial impact point. The wreckage path was approximately 70 feet wide Engine Examination. On-Site Both engines were in place in the engine compartment. Engine mounts remained attached to the engines but were separated from the airframe. The left side of # 1 was crushed. The exhaust collector of # 1 showed deformation. Pneumatic tubing on both engines was bent. Fuel control and power turbine governor linkage on both engines was bent afid broken. Exhaust stacks on both engines were bentlcrushed. The engine compartment cowlings, inlet screens and particle separators were destroyed. The center and forward firewalls were in place but extensively damaged. Both engines were heavily sooted but there was no fire damage. The compressor on # 1 engine showed fresh FOD (foreign object damage). The rotor was able to be turned by hand but it was tight. There was continuity through to the starter generator. The power turbine would not rotate as a result of binding by the deformed exhaust collector. The compressor of # 2 engine was heavily sooted and FODed. The # 1 bearing housing was damaged as a result of the bolt pulling through it. N, was not able to be rotated by hand. Subsequently, a piece of molten metal was found to be lodged between a blade and a vane at the 3rd stage. The power turbine of ## 2 engine was able to rotate when turned by hand. There was continuity through to the PTO.

6 SIN CAE (1) I CAE (2) --- March 10, 2000, Temsco Helicopters Inc. 0 Both engines showed rotation signatures on the main driveshafts. The engine disassembly inspection was conducted at Dallas Airmotive, Dallas, Texas. The left hand engine observation are designated with a (1) and the right hand engine observations are designated with a (2). Observations of the disassembly inspection follow: Pneumatic checks u.ere performed on both engines with 80 psi shop air. No leaks were noted. (1) The fuel filter housing was cracked. All fuel had leaked out. The fuel filter was dirty and there was a considerable amount of debris in the housing. 0 (1) Both magnetic chip detectors were clean and oiled. 0 (1) Oil contained in the accessory gearbox was golden colored and clean. 0 (1) The engine oil filter was clean. 0 (1) The generator shaft and splines were intact. (1 ) The fuel control. fuel pump. and po\ver turbine governor driveshafts and splines were intact. 0 (1) Shafting continuit\, throughout the engine and the accessory gearbox was intact. (1 ) The fuel nozzle was slightly carboned but the spray orifice was open. A bench test of the nozzle showed some streaking. 0 (1) The TOT harness and thermocouples were intact. (1) The 3'd stage turbine wheel showed 360 degree rotational scoring as a result of contact with the stationary 3rd stage nozzle. Metal from the nozzle was deposited on the wheel surface. (1) The impeller shroud showed 360 degree rotational scoring. There was slight penetration into the base metal. 0 (1) No bearing failures were noted. (1) All wheel blades and nozzle vanes were intact. 0 (1) There was no visible damage to the splines of internal engine shafting.

7 SIN CAE (1) I CAE (2) --- March I O, 2000, Ternsco Helicopters Inc. 0 (2) The fuel contained in the fuel filter was cloudy and contained some debris. (2) Oil contained in the gearbox was golden colored and clean. The oil filter was clean. 0 (2) Both magnetic chip detectors were cleaned and oiled. 0 (2) The fuel control. fuel pump, and power turbine governor driveshafts and splines were intact. 0 (2) The PTO bolt studs were bent in the direction of rotation. 0 (2) The fuel nozzle was slightly carboned but the spray orifice \vas open. A bench test of the nozzle showed some streaking. 0 (2) Shafting continuity throughout the engine and the accessory gearbox was intact. 0 (2) The TOT harness and thermocouples were intact. 0 (2) Heavy compressor rub was noted on all stages. 0 (2) Heavy ash deposits were centrifuged outnard on both the jrd and 4"' stage turbine wheels. 0 (2) There were no bearing failures noted. 0 (2) All wheel blades and nozzle vanes \vue intact 0 (2) There was no visible damage to thc splines of internal engine shafting Engine Maintenance and Records. Number 1 Engine, Left Side

8 SIN CAE (1) I CAE (2) --- March I O, 2000, Ternsco Helicopters Inc. Number 2 Engine, Right Side I Bleed Valve I FF53862 I I New I I 2.13 Additional Information. 3. SUMMARY OF FINDINGS. 3.1 External damages to engines were the result of impact forces. 3.2 Internal and external engine signatures were consistent with engine operation at the time of impact. 3.3 Damages to airframe main driveshafts and main rotor system were consistent with engine operation.