# NTSB SEA96LA065: Nicholson Thorp T18CWS, N24WN, Grantsville, UT, February 28, 1996 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: February 27, 1996, 17:20 local (Feb 28, 1996, 00:20 UTC) - Place: Grantsville, UT - Coordinates: 40.670909, -112.759681 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.6709&lon=-112.7597&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report July 25, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 42342 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA96LA065 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42342/pdf - Page: https://openairdocs.org/ntsb/SEA96LA065 ## Probable cause the pilot's failure to maintain clearance from a powerline. A transmission wire and an oil pressure reading of zero were factors. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, go-around (vfr) - engine instruments,oil pressure gage - low pressure (contributing factor) - precautionary landing - performed, pilot in command (contributing factor) - object - wire,transmission (contributing factor) - clearance - not maintained, pilot in command (cause) ## Analysis The pilot reported that while flying at 600 feet above ground level, he noticed that there was no oil pressure indication. He attempted a precautionary landing to a paved road, but had to initiate a go-around because of a truck on the road. During the go-around, the airplane collided with a power line that was approximately 100 feet AGL. The airplane was unable to maintain flight and subsequently collided with the terrain. ## Factual narrative On February 27, 1996, at 1720 mountain standard time, a homebuilt Nicholson Thorp T18CWS, N24WN, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, collided with power lines during a precautionary landing, approximately 25 miles west of Grantsville, Utah. Visual meteorological conditions prevailed at the time and no flight plan was filed. The airplane was substantially damaged and the commercial pilot, the sole occupant, was not injured. The flight originated from Wendover, Utah, about 30 minutes before the accident. During an interview and subsequent written statement, the pilot reported that he was flying one of three planes in a flight en route to Salt Lake City, Utah. The pilot stated that while flying at approximately 600 feet above ground level, he noticed there was no oil pressure. The pilot initiated a precautionary landing to a paved road and noted that there was a truck on the road, but felt that it would be out of the way by the time he landed. The truck, however, was not clear and the pilot initiated a go- around. During the go-around, the airplane collided with a transmission line that was approximately 100 feet above ground level. The airplane was unable to maintain flight and subsequently collided with the terrain. ## Aircraft - Registration: [N24WN](https://openairdocs.org/deregistered/N24WN-2015-05-06), registration cancelled 2015-05-06, S/N 1424 (OpenAirDocs) - Reported make and model: NICHOLSON THORP T18CWS (THORP T18C) - Registry model: [Nicholson William L THORP T18CWS](https://openairdocs.org/model/nicholson-william-l-thorp-t18cws) (registry code 89510R4) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 1424 - Airframe hours: 429 - Engines: Lycoming O-320-E2D 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: William L. Nicholson - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, June 12, 1995, 131 hours before - Departed: ENV, WENDOVER, UT - Destination: U42, SALT LAKE CITY, UT ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 1,930 total, 429 in this make and model, 1,706 as pilot in command, 15 in the last 90 days, 13 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 2 knots - Visibility: 30 statute miles - Lowest ceiling: none - Temperature: 32 °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 19960227003169A](https://openairdocs.org/incident/19960227003169A), Feb 27, 1996: Amtr THORPT18, Grantsville, UT, Substantial damage. Low oil pressure, elected to make emergency landing on service road, hit powerline, crashed. (.4)the pilot reported that while flying at 600 feet above ground… ## Other investigations on N24WN (1) 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 DEN00LA163](https://openairdocs.org/ntsb/DEN00LA163), Sep 3, 2000: Nicholson Thorp T-18CWS (N24WN), Tooele, UT, destroyed, 2 fatal. Probable cause: Failure by the pilot to maintain control of the airplane during aerobatic maneuvers as a result of his alcohol impairment. Factors were: The pilot's inadequate planning and decision making and the… 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.