# NTSB CHI04LA047: Sikorsky S-58JT, N598S, Ypsilanti, MI, December 22, 2003 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: December 22, 2003, 18:06 local (23:06 UTC) - Place: Ypsilanti, MI - Coordinates: 42.237777, -83.530281 - Nearby events: https://openairdocs.org/map.md?lat=42.2378&lon=-83.5303&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report January 24, 2005 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 58687 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI04LA047 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/58687/pdf - Page: https://openairdocs.org/ntsb/CHI04LA047 ## Probable cause The pilot became disoriented and attempted to land the helicopter at the wrong ramp resulting in his failure to maintain obstacle clearance during the approach. The light poles were a factor to the accident. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, landing - became lost/disoriented - inadvertent, pilot in command (cause) - clearance - not maintained, pilot in command (cause) - object - pole (contributing factor) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis The helicopter was destroyed when it impacted light poles and the ground during landing. The pilot stated that he was on a southwest heading to the airport and was cleared to land at the U.S. Customs ramp. The pilot reported that approximately 40 knots airspeed and 70 feet above ground level (agl), "there was an abrupt boom and pitch of the aircraft followed by a right forward rapid decent with a very large horizontal one-to-one out of balance oscillation." The pilot stated that he, "attempted to apply all available collective pitch, which was followed by contact with the ground, followed by rolling and flipping of the aircraft." The pilot reported that after he and the passenger exited the helicopter through a window, they noticed inoperative light poles which stood 70 to 80 feet in height. The light pole that was struck was 45 feet tall and was located at the southwest cargo ramp area near the south end of taxiway D. The light pole is located 4,542 feet south-southwest of the U.S. Customs circle. The light pole is located to the south of runway 09R/27L. The U.S. Customs ramp is located on the west ramp between runways 09R/27L and 09L/27R. ## Factual narrative On December 22, 2003, at 1806 eastern standard time, a Sikorsky S-58JT helicopter, N598S, piloted by a commercial pilot, was destroyed when it impacted light poles and the ground during landing at the Willow Run Airport (YIP), Ypsilanti, Michigan. The 14 CFR Part 135 flight was cleared to land at the United States Customs Service ramp. The flight was operating in night visual meteorological conditions on a visual flight rules flight plan. The pilot and passenger received minor injuries. The flight originated from the Windsor International Airport, Ontario, Canada, at 1745. According to the pilot's statement, he was on a southwest heading on-course to YIP when he contacted YIP tower. He stated that at this time, he was cleared by YIP Tower to land at the U.S. Customs ramp. The pilot reported that approximately 40 knots airspeed and 70 feet above ground level (agl), "there was an abrupt boom and pitch of the aircraft followed by a right forward rapid decent with a very large horizontal one-to-one out of balance oscillation." The pilot stated that he, "attempted to apply all available collective pitch, which was followed by contact with the ground, followed by rolling and flipping of the aircraft." The pilot reported that after he and the passenger exited the helicopter through a window, they noticed inoperative light poles which stood 70 to 80 feet in height. The pilot had made a full-stop landing at YIP earlier on the day of the accident. According to the YIP airport manager, the light pole that was struck was 45 feet tall and was located at the southwest cargo ramp area near the south end of taxiway D. The light pole is located 4,542 feet south-southwest of the U.S. Customs circle. The light pole is located to the south of runway 09R/27L. The U.S. Customs ramp is located on the west ramp between runways 09R/27L and 09L/27R. ## Aircraft - Registration: [N598S](https://openairdocs.org/deregistered/N598S-2004-05-04), registration cancelled 2004-05-04, S/N 58-1196, built 1960 (OpenAirDocs) - Reported make and model: Sikorsky S-58JT - Registry model: [Sikorsky S-58DT](https://openairdocs.org/model/sikorsky-s-58dt) (registry code 8141842) (OpenAirDocs) - Registry engine: [Pratt & Whitney Canada PT6T-6](https://openairdocs.org/engine/pratt-whitney-canada-pt6t-6) (registry code 52106, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 58-1196 - Airframe hours: 8342 - Engines: Pratt & Whitney Canada PT6T-6 1675 horsepower turbo shaft; Pratt & Whitney Canada PT6T-6 1675 horsepower turbo shaft - Damage: Destroyed - Flight: Part 135 - Registered owner: McMahon Helicopter Service Inc. - Airworthiness certificate: Standard, Transport - Last inspection: AAIP, November 8, 2003, 34 hours before - Departed: YQG, WINDSOR ONT - Destination: KYIP, Ypsilanti, MI - Flight plan: VFR - Airport: YIP, Willow Run ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: minor; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter; medical: class 2, valid medical--no waivers/lim.; last flight review March 28, 2003; seat: right; flight hours: 15,760 total, 77 in this make and model, 15,504 as pilot in command, 40 in the last 90 days, 8 in the last 30 days ## Weather - Conditions: Visual (VMC), Night - Wind: 220° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: 12,000 ft broken - Temperature: 43 °F, dew point 37 °F - Altimeter: 29.90 inHg - Observed at: KYIP ## 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 20031222033589A](https://openairdocs.org/incident/20031222033589A), Dec 22, 2003: Skrsky S58DT, Detroit, MI, Destroyed. (-23) On dec. 22, 2003 1805 local time at willor run airport (yip) a sikorski helicopter N598S called Willow Run tower, 6 miles east landing customs. Willow… 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.