# NTSB ATL04CA186: Cessna 172RG, N948SM, Montgomery, AL, September 15, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: September 15, 2004, 10:45 local (15:45 UTC) - Place: Montgomery, AL - Coordinates: 32.300556, -86.39389 - Nearby events: https://openairdocs.org/map.md?lat=32.3006&lon=-86.3939&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 3, 2004 - Report: Approved by Office Director - Parties: Birmingham FSDO - 09 - NTSB case key (mKey): 60140 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL04CA186 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/60140/pdf - Page: https://openairdocs.org/ntsb/ATL04CA186 ## Probable cause The separation of a hydraulic line for undetermined reasons, which resulted in a hydraulic fluid leak and malfunction of the landing gear. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, cruise - hydraulic system,line - separation (cause) - hydraulic system,line - leak - Gear collapsed, landing - flare/touchdown - On ground/water collision with object, landing - flare/touchdown - object - taxiway light ## Analysis During cruise flight, the pilot heard and felt a "thud" and detected an odor of "hydraulic fluid burning." The pilot diverted to an airport for landing, and his attempts to lower the landing gear using both normal and emergency procedures were unsuccessful. When the airplane touched down on the runway, the landing gear collapsed, and the airplane veered left and struck a taxiway light. Examination revealed the landing gear would not function. The landing gear hydraulic system was found depleted of fluid, and a hydraulic line on the nose gear actuator was found separated from its swedge fitting. Examination of the line revealed no evidence of abnormal wear. A review of Service Difficulty Reports on file with the Federal Aviation Administration for Cessna 172RGs revealed one similar event reported in 2001 in which a hydraulic line on the nose gear actuator was found separated from its swedge fitting. ## Factual narrative On September 15, 2004, at 1045 central daylight time, a Cessna 172RG, N948SM, registered to and operated by the private pilot, collided with a taxiway light following a collapse of the landing gear at Montgomery Regional - Dannelly Field, Montgomery, Alabama. The personal flight was operated under the provisions of Title 14 CFR Part 91 with an instrument flight plan filed but not activated. Visual meteorological conditions prevailed. The private pilot reported no injuries, and the airplane sustained substantial damage. The flight departed George Downer Airport, Aliceville, Alabama, about 1000 on September 15, 2004. The flight was en route to Craig Field, Selma, Alabama, under visual flight rules. The pilot reported that, while in cruise flight approximately 15 minutes into the flight, he heard and felt a "thud" and detected an odor of "hydraulic fluid burning." The pilot elected to divert to Montgomery Regional - Dannelly Field. The pilot stated he attempted to lower the landing gear using the gear lever, and he heard noise and felt vibrations but he could not see the main wheels. The pilot stated he cycled the gear lever, and the circuit breaker popped out. The pilot stated he waited a few minutes, reset the circuit breaker, and the "amp gauge showed a total discharge and the low voltage light came on," and the circuit breaker immediately popped out again. The pilot stated he then followed the emergency gear extension procedures, but the circuit breaker would not stay in. He stated he placed the gear lever down, extended the emergency pump handle, and pumped 30 to 40 times but felt no pressure on the lever. A Montgomery tower controller verified to the pilot the landing gear did not appear completely down. The pilot executed a landing on runway 10, and all wheels collapsed beneath the airplane. The pilot stated the airplane touched down tail-low on the runway, slid on its belly down the runway for approximately 100 to 150 feet, then it jerked abruptly to the left, struck a taxiway light, and spun around in the grass. Examination of the airplane revealed the landing gear was collapsed, and the right wing spar and the right side of the elevator were damaged. The airplane was placed on jacks by maintenance personnel, and the landing gear did not function when both normal and emergency procedures were performed. The landing gear hydraulic system was found depleted of fluid. A hydraulic line on the nose gear actuator was found separated from its swedge fitting. Examination of the line revealed no evidence of abnormal wear. A review of Service Difficulty Reports on file with the Federal Aviation Administration for Cessna 172RGs revealed one similar event reported in 2001 in which a hydraulic line on the nose gear actuator was found separated from its swedge fitting. ## Aircraft - Registration: [N948SM](https://openairdocs.org/aircraft/N948SM), registered now, S/N 172RG1057, built 1982 (OpenAirDocs) - Reported make and model: Cessna 172RG - Registry model: [Cessna 172RG](https://openairdocs.org/model/cessna-172rg) (registry code 2072438) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 172RG1057 - Engines: Lycoming O-360 reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: George L Ousley - Airworthiness certificate: Standard, Normal - Departed: KAIV, Aliceville, AL - Destination: KSEM, Selma, AL - Flight plan: IFR - Airport: KMGM, Montgomery Reg/Dannelly Field, runway 10 ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3; flight hours: 2,300 total, 140 in this make and model, 26 in the last 90 days, 9 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 70° at 14 knots, gusting 21 - Visibility: 10 statute miles - Lowest ceiling: 1,300 ft overcast - Temperature: 75 °F, dew point 68 °F - Altimeter: 30.01 inHg - Observed at: KMGM ## 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 20040915021589A](https://openairdocs.org/incident/20040915021589A), Sep 15, 2004: Cessna 172RG, Montgomery, AL, Substantial damage. (-23) The pilot departed aliceville (aiv) at 1000 hours enroute VFR to selma (sem). Over vaiden a "thud" was felt (approx 1015) and he started smelling… 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.