# NTSB DEN02LA051: Enstrom F-28C, N5694Z, Medicine Bow, WY, June 10, 2002 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: June 10, 2002, 09:30 local (15:30 UTC) - Place: Medicine Bow, WY - Coordinates: 41.733333, -106.199996 - Nearby events: https://openairdocs.org/map.md?lat=41.7333&lon=-106.2000&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 1 minor - Status: Completed, report December 6, 2002 - Report: Approved by Office Director - Parties: Enstrom Helicopter Corporation, Textron Lycoming, Federal Aviation Administration - NTSB case key (mKey): 54892 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN02LA051 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/54892/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=54892 - Page: https://openairdocs.org/ntsb/DEN02LA051 ## Probable cause the unsuitable terrain encountered during the emergency autorotation, following a partial loss of engine power. Factors contributing to this accident were fuel contamination (water), the low altitude, the high winds, and the tailwind. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - nonmechanical, maneuvering - turn to reverse direction - fluid,fuel - contamination,water (contributing factor) - Forced landing, emergency descent/landing - autorotation - performed, pilot in command - Hard landing, emergency descent/landing - unsuitable terrain or takeoff/landing/taxi area - encountered (cause) - altitude - low (contributing factor) - weather condition - high wind (contributing factor) - weather condition - tailwind (contributing factor) ## Analysis The pilot reported that he was conducting pipeline patrol and marking the positions of pipeline valves using a global positioning satellite receiver. The pilot said weather was clear but windy. Approximately 1 hour into the flight, the pilot made a turn to the west to come around over a location, and continued in the turn back to the east downwind. The pilot said he rolled out of the turn and started to pull some power for the turn back to the right to pick up the pipeline again when the helicopter yawed right and started losing power. The pilot said he immediately "lowered the collective, added throttle, and turned left to the north." The pilot said he was approximately 100 feet above the ground and had an airspeed of about 60 miles per hour. "With the bank and the autorotation I was able to stop forward motion and ground speed. I flared the helicopter, pulled pitch, and hit flat." The pilot said he shut down the engine after impact. "As far as I could tell the power never came back during the autorotation." An examination of the helicopter's fuel system showed water in the left and right fuel tanks. No other anomalies were found. ## Factual narrative On June 10, 2002, at 0930 mountain daylight time, an Enstrom F-28C, N5694Z, operated by Falcon Helicopter, Inc., and piloted by a commercial pilot, was substantially damaged during a hard landing that occurred 10 miles south of Medicine Bow, Wyoming. Visual meteorological conditions prevailed at the time of the accident. The business flight was for conducting pipeline patrol under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot sustained serious injuries in the accident. The passenger on board the helicopter sustained minor injuries. The flight originated at Laramie, Wyoming, at 0830, and was to terminate at Rawlins, Wyoming . The pilot reported that he was conducting pipeline patrol and marking the positions of pipeline valves using a global positioning satellite receiver. In his written statement, the pilot said they picked up the pipeline at the northwest side of Laramie and proceeded northwest. "The weather was clear but windy. At about 0930 we made a turn to the west to come around over a location, and continued in the turn back to the east downwind. I rolled out of the turn and started to pull some power for the turn back to the right to pick up the pipeline again when the helicopter yawed right and started losing power." The pilot said he immediately "lowered the collective, added throttle, and turned left to the north." The pilot said he was approximately 100 feet above the ground and had an airspeed of about 60 miles per hour. "With the bank and the autorotation I was able to stop forward motion and ground speed. I flared the helicopter, pulled pitch, and hit flat." The pilot said he shut down the engine after impact. "As far as I could tell the power never came back during the autorotation." In a subsequent interview, the pilot reported that he had flown to Laramie, from Longmont, Colorado, earlier that morning. At Laramie, the pilot had the helicopter's fuel topped off. The pilot said that the fixed base operator at Laramie, told him that they were having trouble with their refueling truck, but didn't know what that was. The pilot said that the helicopter's attitude during takeoff, climb out, and during the flight to the location where they maneuvered, was level. He said that after completing the turn and on downwind, there was a stiff wind of about 25 knots. The pilot said that he was starting to initiate the turn to get back on the pipeline and was pulling power when the power started bleeding off. The pilot said, "It seemed like it sucked bad fuel." The helicopter came to rest upright in an open field. A preliminary examination of the helicopter showed the left skid broken upward and the bottom of the fuselage crushed upward. The tail boom was broken off, aft of the baggage compartment. The forward windscreen and chin windows were broken out. The trailing edges of two of the three main rotor blades were bent downward, wrinkled, torn, and twisted. The tail rotor gear box was broken out and found resting on the ground in front of the helicopter cabin. The tail rotor blades were bent outward. The helicopter's engine was retained for further examination. The National Transportation Safety Board examined the helicopter at Greeley, Colorado, on June 25, 2002. Fuel samples were taken at the sump drains to the left and right fuel tanks, and the fuel strainer. The fuel sample taken from the left tank showed approximately 2 ounces of water. Fuel samples from the right tank and the fuel strainer showed no water. The engine was started and run. No anomalies were found during the engine run. The helicopter was then defueled. Approximately 25 gallons of fuel was drained from the helicopter's two tanks. An additional 4 ounces of water was recovered from the bottom of the helicopter's right fuel tank. ## Aircraft - Registration: [N5694Z](https://openairdocs.org/deregistered/N5694Z-2013-04-23), registration cancelled 2013-04-23, S/N 497-2, built 1980 (OpenAirDocs) - Reported make and model: Enstrom F-28C - Registry model: [Enstrom F-28C](https://openairdocs.org/model/enstrom-f-28c) (registry code 3300407) (OpenAirDocs) - Registry engine: [Lycoming I0360 series](https://openairdocs.org/engine/lycoming-i0360-series) (registry code 41515, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 497-2 - Airframe hours: 1999.9 - Engines: Lycoming HIO-360-E1AD 205 horsepower reciprocating - Damage: Substantial damage - Flight: Business, Part 91 - Operator: Falcon Helicopter, Inc., doing business as Falcon Helicopters, Inc - Registered owner: Timothy C. Rhoads - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, May 10, 2002, 148 hours before - Departed: LAR, Laramie, WY - Destination: RWL, Rawlins, WY ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: serious; commercial, flight instructor; airplane ratings: single-engine land; instrument ratings: helicopter, airplane; medical: class 2; last flight review January 17, 2001; seat: left; flight hours: 10,418 total, 8,000 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 340° at 11 knots, gusting 14 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 48 °F, dew point 18 °F - Altimeter: 29.97 inHg - Observed at: LAR, 36 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 20020610013889A](https://openairdocs.org/incident/20020610013889A), Jun 10, 2002: Enstrm F28C, Medicinebow, WY, No damage. (-23) The pilot was about 100 feet above the ground making a down wind turn when the helicopter lost power. He then went into autorotation and impacted the… ## Docket (14 files) The files NTSB released with the investigation on October 29, 2002, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=54892. 3.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 323 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40444148&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Supplement S (item 2, .PDF, 37 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164145&FileExtension=.PDF&FileName=Supplement%20S-Master.PDF - Pilot Interview (item 3, .PDF, 55 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40444149&FileExtension=.PDF&FileName=Pilot%20Interview-Redacted.PDF - Weather Reports and Records (item 4, .PDF, 49 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164148&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 5, .PDF, 327 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40444150&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 6, .PDF, 49 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40444151&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF - Photo 1 - Accident Site, Helicopter Main Wreckage (item 7, .PDF, 220 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164151&FileExtension=.PDF&FileName=Photo%201%20-%20Accident%20Site,%20Helicopter%20Main%20Wreckage-Master.PDF - Photo 2 - Helicopter Main Wreckage, Aft View (item 8, .PDF, 180 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164152&FileExtension=.PDF&FileName=Photo%202%20-%20Helicopter%20Main%20Wreckage,%20Aft%20View-Master.PDF - Photo 3 - Helicopter Main Wreckage, Front View (item 9, .PDF, 279 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164153&FileExtension=.PDF&FileName=Photo%203%20-%20Helicopter%20Main%20Wreckage,%20Front%20View-Master.PDF - Photo 4 - Helicopter Main Wreckage, Debris Field (item 10, .PDF, 247 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164154&FileExtension=.PDF&FileName=Photo%204%20-%20Helicopter%20Main%20Wreckage,%20Debris%20Field-Master.PDF - Photo 5 - Helicopter Main Wreckage, Left, Aft View (item 11, .PDF, 250 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164156&FileExtension=.PDF&FileName=Photo%205%20-%20Helicopter%20Main%20Wreckage,%20Left,%20Aft%20View-Master.PDF - Photo 6 - Fuel Sample (item 12, .PDF, 726 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164157&FileExtension=.PDF&FileName=Photo%206%20-%20Fuel%20Sample-Master.PDF - Photo 7 - Fuel Sample (item 13, .PDF, 155 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164158&FileExtension=.PDF&FileName=Photo%207%20-%20Fuel%20Sample-Master.PDF - Photo 8 - Fuel Sample, Close up View (item 14, .PDF, 159 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40164159&FileExtension=.PDF&FileName=Photo%208%20-%20Fuel%20Sample,%20Close%20up%20View-Master.PDF From the NTSB's public API. 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