# NTSB LAX99LA238: Cessna 150M, N63614, Honolulu, HI, June 30, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: June 30, 1999, 12:10 local (22:10 UTC) - Place: Honolulu, HI - Coordinates: 21.35003, -157.880249 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=21.3500&lon=-157.8802&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report August 14, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 46748 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX99LA238 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/46748/pdf - Page: https://openairdocs.org/ntsb/LAX99LA238 ## Probable cause The airplane's encounter with turbulent air from the rotor wash of a large military helicopter, which resulted from the instructor's decision to continue the approach while the helicopter was on the runway. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Vortex turbulence encountered, go-around (vfr) - unsafe/hazardous condition warning - disregarded, pilot in command(cfi) (cause) - altitude/clearance - not maintained, pilot in command(cfi) (cause) - flight into adverse weather - continued, pilot in command(cfi) (cause) - Loss of control - in flight, go-around (vfr) - aircraft control - not maintained, pilot in command(cfi) (cause) - In flight collision with terrain/water, descent - uncontrolled ## Analysis On the downwind leg of the traffic pattern for the joint civil/military airport, the instructor saw a Navy UH3H helicopter on the base leg to the same runway. The CTAF operator cautioned them about wake turbulence. The student asked if he should extend the downwind, but the instructor advised him to just stay above the helicopter's flight path. The instructor said that while turning to the base leg, they could see that the helicopter was still on the runway. On short final approach nearing the runway, the instructor announced their position on the CTAF. The helicopter remained on the runway, so the instructor advised the student to go around. At that point, the airplane was slightly past the runway threshold and the helicopter was about 2,500 feet down the 4,000-foot runway. The instructor stated that as the student initiated the go-around, the aircraft encountered some turbulence, and rolled 90 degrees to the right. The instructor then noticed the helicopter lifting off the ground. He took over the controls but had difficulty maintaining control of the aircraft. He stated that he attempted to fly out of the rotor wash, but didn't have sufficient altitude to maneuver safely. The airplane sank onto its right wing, bounced, and landed on the nose gear, which then collapsed. The airport is an auxiliary landing field for a naval air station. According to the airport facility directory, civil operations were permitted, but limited to daylight VFR conditions, and all aircraft must conform to the traffic pattern and CTAF advisories. ## Factual narrative On June 30, 1999, about 1210 hours Hawaiian standard time, a Cessna 150M, N63614, collided with the ground while landing at the Ford Island Airstrip, Honolulu, Hawaii, after encountering rotor wash from a nearby military helicopter. The aircraft, owned and operated by Oahu Aviation Flight School, Inc., Honolulu, sustained substantial damage. The commercial pilot/certified flight instructor and a student pilot were not injured. The local area instructional flight was conducted under the provisions of 14 CFR Part 91, and originated at the Honolulu airport at 1130. Visual meteorological conditions prevailed and no flight plan was filed. The instructor reported that they were practicing soft and short field landings to runway 4. He stated that while they were on the downwind leg of the traffic pattern, they observed a Navy UH3H helicopter on the base leg to the same runway. He reported that the CTAF (Common Traffic Advisory Frequency) operator advised them, "Caution: wake turbulence." The student asked if he should extend the downwind, but the instructor told him that it wasn't necessary and advised him to just stay above the helicopter's flight path. The instructor reported that while turning to the base leg, they could see that the helicopter was still on the runway. They could hear the CTAF operator talking to the helicopter crew, but could not hear any transmissions from the helicopter. As they began a short final approach nearing the runway, the instructor announced their position on the CTAF. The helicopter remained on the runway, so the instructor advised the student to go around. At that point, the airplane was slightly past the runway threshold and the helicopter was approximately 2,500 feet down the 4,000-foot runway. The instructor stated that as the student initiated the go-around, the aircraft encountered some "turbulence." They felt several "bumps" and the aircraft rolled 90 degrees to the right. The instructor then noticed the helicopter lifting off the ground. He took over the controls but had difficulty maintaining control of the aircraft. He stated that he attempted to fly out of the rotor wash, but didn't have sufficient altitude to maneuver safely. The airplane sank onto its right wing, bounced, and landed on the nose gear, which then collapsed. The instructor reported that there were no mechanical problems with the aircraft or engine prior to the accident. A Federal Aviation Administration (FAA) inspector from the Honolulu Flight Standards District Office (FSDO) responded to the accident site. He reported that the winds at the Ford Island Airstrip at the time of the accident were steady from approximately 040 degrees at 10 to 15 knots. Another FAA inspector, also from the Honolulu FSDO, interviewed the pilot and copilot of the helicopter. The copilot stated that everything was normal during the landing, and when they were at the proper angle to the landing pad, they maneuvered the helicopter toward the pad and touched down. She stated that she was unaware that an accident had occurred. The pilot reported that a few feet from the helicopter pad he noticed someone outside on the left side of the helicopter waving and pointing to the area of the crash. He stated that he looked out of the window and saw people running toward the accident site. Neither the pilot nor the copilot reported receiving any advisories on the CTAF frequency after landing. Further research revealed that the airport was an auxiliary landing field for the Naval Air Station at Barbers Point, Hawaii. According to the airport facility directory, civil operations were permitted, but limited to daylight VFR conditions. It also stated that all aircraft must conform to the traffic pattern and CTAF advisories, and that all aircraft must contact the Ford CTAF control prior to entering the traffic pattern, and maintain contact while operating in the Ford area. The FAA inspector reported that most military aircraft broadcast on UHF, while civil aircraft broadcast on VHF. At the time of the accident, the helicopter was communicating with the CTAF operator on UHF and N63614 was communicating on VHF; therefore, the helicopter was unable to hear the position reports of the landing aircraft. ## Aircraft - Registration: [N63614](https://openairdocs.org/deregistered/N63614-2013-04-29), registration cancelled 2013-04-29, S/N 15077429, built 1975 (OpenAirDocs) - Reported make and model: Cessna 150M - Registry model: [Cessna 150M](https://openairdocs.org/model/cessna-150m) (registry code 2071830) (OpenAirDocs) - Registry engine: [Continental 0-200 series](https://openairdocs.org/engine/continental-0-200-series) (registry code 17020, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 15077429 - Airframe hours: 10037 - Engines: Continental O-200-A 100 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Oahu Aviation - Airworthiness certificate: Standard, Utility; Standard, Normal - Last inspection: Annual, June 10, 1999, 36 hours before - Departed: HNL, HI - Destination: NPS - Airport: NPS, Ford Island Airstrip, runway 4, 4,000 × 50 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 37; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: right; flight hours: 1,250 total, 900 in this make and model, 1,150 as pilot in command, 200 in the last 90 days, 71 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 60° at 10 knots - Visibility: 10 statute miles - Lowest ceiling: 2,900 ft broken - Temperature: 79 °F, dew point 66 °F - Altimeter: 30.00 inHg - Observed at: HNL ## 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 19990630022389A](https://openairdocs.org/incident/19990630022389A), Jun 30, 1999: Cessna 150M, Honolulu, HI, Substantial damage. (.19) On June 30, 1999, at 1210 hours Hawaii standard time, a Cessna 150M, N63614, landed hard after encountering rotor wash from a nearby military helicopter… 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.