# NTSB FTW97LA180: Cessna 172N, N733WJ, Las Cruces, NM, May 7, 1997 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: May 6, 1997, 19:30 local (May 7, 1997, 01:30 UTC) - Place: Las Cruces, NM - Location: 32.3123° N, 106.7783° W: Placed by OpenAirDocs: center of Las Cruces, NM, within about 6 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=32.3123&lon=-106.7783&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed, report February 2, 1998 - Report: Approved by Office Director - NTSB case key (mKey): 20212 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW97LA180 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/20212/pdf - Page: https://openairdocs.org/ntsb/FTW97LA180 ## Probable cause The improper installation of the throttle arm castellated nut, which resulted in a partial loss of power. A factor was the lack of suitable terrain for the forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, cruise - normal - throttle/power lever - loose part/bolt/nut/clamp/etc (cause) - maintenance,installation - improper, other maintenance personnel (cause) - Forced landing, emergency descent/landing - Nose over, landing - roll - terrain condition - none suitable (contributing factor) - terrain condition - high vegetation ## Analysis The pilot reported that while in cruise flight the engine RPM decreased to 2,100. He pulled the throttle out and the RPM decreased to 1,900 RPM. He then applied full throttle and the RPM only increased to 2,000. A forced landing was performed to a young pecan orchard. Examination of the aircraft's fuel system revealed that the right fuel tank had approximately 20 gallons of fuel, and the left fuel tank was empty. Further examination of the aircraft's throttle assembly revealed that the throttle arm castellated nut was loose, and the cotter pin was missing allowing the throttle arm to move without actuating the throttle shaft. A review of the maintenance records revealed the throttle shaft was replaced 6.2 hours earlier during an annual inspection. The person who performed the throttle shaft replacement reported that the airplane left his facility with the cotter pin installed. ## Factual narrative On May 6, 1997, at 1930 mountain daylight time, a Cessna 172N, N733WJ, registered to and operated by a private owner as a Title 14 CFR Part 91 personal flight, was substantially damaged during a forced landing following a partial loss of power near, Las Cruces, New Mexico. Visual meteorological conditions prevailed, and a flight plan was not filed for the cross country flight. The airline transport rated pilot and his two passengers were not injured. The flight originated from St. Johns, Arizona, about 2 hours and 40 minutes prior to the accident. The pilot reported to the FAA inspector that while in cruise flight the engine RPM decreased to 2,100. He pulled the throttle out and the RPM decreased to 1,900 RPM. He then applied full throttle and the RPM only increased to 2,000. The pilot performed a forced landing to a young pecan orchard and the airplane nosed over. Examination of the aircraft by the FAA inspector revealed that both wings sustained structural damage, and the nose landing gear and right main landing gear were separated from the fuselage. Examination of the aircraft's fuel system revealed that the right fuel tank contained approximately 20 gallons of fuel, and the left fuel tank was empty. Further examination of the aircraft's throttle assembly revealed that the throttle arm castellated nut was loose, and the cotter pin was missing allowing the throttle arm to move without actuating the throttle shaft. A review of the maintenance records revealed the throttle shaft was replaced 6.2 hours earlier during an annual inspection. The person who performed the throttle shaft replacement reported that the airplane left his facility with the cotter pin installed. Repeated attempts to obtain a completed Pilot/Operator Accident Report, NTSB Form 6120.1/2, were unsuccessful. ## Aircraft - Registration: [N733WJ](https://openairdocs.org/deregistered/N733WJ-2017-06-20), registration cancelled 2017-06-20, S/N 17268604, built 1977 (OpenAirDocs) - Reported make and model: Cessna 172N - Registry model: [Cessna 172N](https://openairdocs.org/model/cessna-172n) (registry code 2072434) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 17268604 - Airframe hours: 6585 - Engines: Lycoming O-320-H2AD 160 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: James D. Hossler - Registered owner: Latrenda D. Hossler - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 10, 1996, 6 hours before - Departed: SJN, ST. JOHNS, AZ - Destination: ELP, EL PASO, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 40; flight instructor, commercial, airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3, expired; seat: left; flight hours: 8,000 total ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 3 knots - Lowest ceiling: none ## 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 19970507008489A](https://openairdocs.org/incident/19970507008489A), May 7, 1997: Cessna 172N, Las Cruces, NM, Substantial damage. Lost partial power. Nosed over landing throttle arm disconnected. Cotter pin and nut missing. Shaft recent repair. (-23) on may 6, 1997, at approximately 1915… 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.