# NTSB WPR14LA368: Piper PA 24-250, N5966P, Mesa, AZ, September 6, 2014 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 6, 2014, 12:26 local (19:26 UTC) - Place: Mesa, AZ - Coordinates: 33.460834, -111.728614 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.4608&lon=-111.7286&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report November 15, 2017 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 90036 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR14LA368 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90036/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90036 - Page: https://openairdocs.org/ntsb/WPR14LA368 ## Probable cause The failure of the right main landing gear (MLG) transmission mounting bracket coupled with the differential rigging of the two landing gear cables, which prevented the right MLG from moving to the down-and-locked position before landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: main landing gear](https://openairdocs.org/ntsb-findings/01023210): Aircraft › Aircraft systems · Damaged/degraded (probable cause); cases with it: [Piper PA-24-250, 2 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md?model=7102404), [All aircraft, 241 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md) - [Landing gear system: main landing gear](https://openairdocs.org/ntsb-findings/01023210): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Piper PA-24-250, 2 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md?model=7102404), [All aircraft, 241 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md) - [Landing gear system: main landing gear](https://openairdocs.org/ntsb-findings/01023210): Aircraft › Aircraft systems · Not specified (probable cause); cases with it: [Piper PA-24-250, 2 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md?model=7102404), [All aircraft, 241 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event); cases with it: [Piper PA-24-250, 9 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=7102404), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The airline transport pilot reported that, during the approach to land, the right main landing gear (MLG) would not extend and lock, and the locked gear-down position would not illuminate. The pilot attempted to manually extend the gear and get it to lock without success. The pilot then conducted a normal landing, and during the rollout, the right MLG collapsed. Examination of the airplane revealed that the two landing gear cables were rigged slightly differently and that the right bracket that connected the landing gear transmission to the airframe was broken off. Examination of the break with a magnifying glass revealed that it likely had not occurred recently. With the airplane on jacks and the landing gear cables disconnected, the MLG successfully locked down, and the MLG could be manually returned to the "up" position with no restrictions. The airplane experienced a gear-up landing 13 years before the accident, and it is likely that the differential rigging of the two gear cables had existed since that time and led to the MLG being just on the edge of locking. The broken bracket that connected the MLG transmission to the airframe likely fractured some time before the accident and eventually separated from the airframe. The separation of the right MLG transmission bracket coupled with the differential rigging of the two landing gear cables likely prevented the right MLG from moving over center to the "locked" position and resulted in the gear-up landing. ## Factual narrative On September 6, 2014, at 1226 mountain standard time, a Piper PA24-250, N5966P, had the right main landing gear collapse during the landing roll at Falcon Field Airport, Mesa, Arizona. The airline transport pilot and one passenger were uninjured; the airplane sustained substantial damage to the right wing. The owner/pilot was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The cross-country flight departed Nephi, Utah, about 0930 with a planned destination of Mesa. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that on approach to land the right main landing gear would not extend and indicate a locked gear down position. After a low fly by, the pilot attempted to manually extend the gear but was unable to get a safe gear indication. The pilot made a normal landing and during the roll out the right main landing gear collapsed. The pilot stated that the airplane and engine had no mechanical failures or malfunctions during the flight. A Federal Aviation Administration inspector examined the wreckage. He discovered that the rigging of the two landing gear cables was slightly off. The bracket that connected the landing gear transmission to the airframe was broken off; when examined with a magnifying glass, the break did not appear to have occurred recently. With the airplane on jacks and the landing gear cables disconnected, the gear successfully locked down, and the gear could be manually returned to the up position with no restrictions. He determined that the airplane had a gear up landing in 2001. ## Aircraft - Registration: [N5966P](https://openairdocs.org/aircraft/N5966P), registered now, S/N 24-1059, built 1959 (OpenAirDocs) - Reported make and model: PIPER PA 24-250 - Registry model: [Piper PA-24-250](https://openairdocs.org/model/piper-pa-24-250) (registry code 7102404) (OpenAirDocs) - Registry engine: [Lycoming 0-540 series](https://openairdocs.org/engine/lycoming-0-540-series) (registry code 41532, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 24-1059 - Year built: 1959 - Engines: LYCOMING O-540 SERIES 250 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, December 1, 2013 - Departed: U14, NEPHI, UT - Destination: FFZ, Mesa, AZ - Airport: FFZ, Falcon Fld, runway 22R, 3,799 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 83; injuries: none; flight instructor, commercial, airline transport; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 3, without waivers/limitations; last flight review May 1, 2013; seat: left; restraint: lap only; flight hours: 13,201 total, 1,223 in this make and model, 13,071 as pilot in command, 15 in the last 90 days, 11 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 210° at 6 knots - Visibility: 40 statute miles - Temperature: 99 °F, dew point 61 °F - Altimeter: 29.88 inHg - Observed at: KFFZ ## 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 20140906016359A](https://openairdocs.org/incident/20140906016359A), Sep 6, 2014: Piper PA-24-250, Mesa, AZ, Substantial damage. Upon final approach to runway 22R, all systems were normal and the pilot had a green gear down indication. At approx 30 feet before touch down, the pilot felt… ## Docket (2 files) The files NTSB released with the investigation on October 16, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90036. 888 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 677 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457063&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - FAA Examination Report (item 2, .PDF, 211 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457064&FileExtension=.PDF&FileName=FAA%20Examination%20Report-Master.PDF 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.