# NTSB CEN19LA246: Swearingen SA227, N681TR, El Paso, TX, July 27, 2019 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: July 27, 2019, 05:35 local (11:35 UTC) - Place: El Paso, TX - Coordinates: 31.807222, -106.376388 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=31.8072&lon=-106.3764&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern downwind: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: FAA Flight Standards - NTSB case key (mKey): 99971 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN19LA246 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/99971/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=99971 - Page: https://openairdocs.org/ntsb/CEN19LA246 ## Probable cause Failure of the left main landing gear to fully extend due to a lack of hydraulic fluid and during emergency extension procedures, which resulted in the collapse of the landing gear during landing and the subsequent runway excursion and collision with a sign. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: gear extension and retract sys](https://openairdocs.org/ntsb-findings/01023230): Aircraft › Aircraft systems · Malfunction (probable cause); cases with it: [Fairchild SA227-AC, 1 case](https://openairdocs.org/ntsb-findings/01023230/cases.md?model=3377509), [All aircraft, 416 cases](https://openairdocs.org/ntsb-findings/01023230/cases.md) - [Hydraulic power system: hydraulic, main system](https://openairdocs.org/ntsb-findings/01022910): Aircraft › Aircraft systems · Malfunction (probable cause); cases with it: [Fairchild SA227-AC, 1 case](https://openairdocs.org/ntsb-findings/01022910/cases.md?model=3377509), [All aircraft, 27 cases](https://openairdocs.org/ntsb-findings/01022910/cases.md) - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Fairchild SA227-AC, 1 case](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=3377509), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern downwind: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Fairchild SA227-AC, 2 cases](https://openairdocs.org/ntsb-events/330/sequence.md?model=3377509), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Landing-flare/touchdown: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Fairchild SA227-AC, 3 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=3377509), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) - [Landing-landing roll: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Fairchild SA227-AC, 4 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=3377509), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md) - [Landing-landing roll: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Fairchild SA227-AC, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=3377509), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The captain noted that the purpose of the flight was second-in-command pilot training for the first officer and the observer, in turn. He reported that after takeoff, the landing gear retracted normally. The captain executed a practice instrument approach to a missed approach. When they attempted to retract the landing gear after initiating the missed approach, the left main gear in-transit light remained illuminated. The right main and nose landing gears retracted normally. Both hydraulic system low pressure warning lights subsequently illuminated. Efforts to troubleshoot using the emergency checklist and to extend the landing gear manually were not successful. The captain ultimately landed the airplane with the left main landing gear partially extended and subsequently lost directional control, which resulted in a runway excursion and impact with an airport sign. The airplane sustained damage to the outboard left wing, left main landing gear, and left propeller. During a postaccident examination, hydraulic fluid was observed in the left main landing gear wheel well; no hydraulic fluid was observed in the reservoir sight gauge or on the dip stick. Hydraulic pressure was subsequently applied to the airplane, and no leaks were observed in the landing gear system. Thus, the source of the hydraulic fluid leak could not be determined. In addition, the reason that the landing gear failed to fully extend during the emergency extension procedure could not be determined because no preaccident anomalies were observed. ## Factual narrative On July 27, 2019, about 0535 mountain daylight time, a Swearingen SA227 airplane, N681TR, was substantially damaged when the left main landing gear collapsed during landing at the El Paso International Airport (ELP), El Paso, Texas. The captain, first officer, and observer were not injured. The airplane was registered to Sierra West Airlines, Inc. and operated by Pak West Airline dba Sierra West Airlines as a Title 14 Code of Federal Regulations Part 91 instructional flight. Visual meteorological conditions prevailed, and the flight was not operated on a flight plan. The local flight originated from ELP about 0430. The captain noted the purpose of the flight was second-in-command pilot training for the first officer and the observer in turn. He reported that after takeoff the landing gear retracted normally. They executed a practice instrument approach to a missed approach. When attempting to retract that landing gear after initiating the missed approach, the left main gear in-transit light remained illuminated. The right main and nose landing gears retracted normally. Both hydraulic system low pressure warning lights subsequently illuminated. Efforts to troubleshoot the problem using the emergency checklist and extend the landing gear manually were not successful. The captain ultimately landed with the left main landing gear partially extended. The subsequent loss of directional control resulted in a runway excursion and an impact with an airport sign. A postaccident examination revealed damage to the outboard left wing, left main landing gear and left propeller. Some hydraulic fluid was present in the left main landing gear wheel well and no hydraulic fluid was observed in the reservoir sight gauge or on the dip stick. The base manager for the airline reported that the left main landing gear drag brace failed consistent with the accident. The actuator and brace were replaced to allow the airplane to "stand" on the left main landing gear. Hydraulic pressure was subsequently applied to the airplane, and no leaks were observed in the landing gear system. A leak was observed in the hydraulic line to the left flap; however, that also appeared to have been a result of the accident. Airplane maintenance records indicated that hydraulic fluid leaks in the left main landing gear wheel well were noted on June 25th and again on 26th; about 30 days before the accident flight. These were repaired and the airplane was returned to service. On June 30th, the hydraulic fluid level was low and was replenished. About 30 hours flight time elapsed between that maintenance action and the accident. ## Aircraft - Registration: [N681TR](https://openairdocs.org/aircraft/N681TR), registered now, S/N AC682, built 1987 (OpenAirDocs) - Reported make and model: SWEARINGEN SA227 (AC) - Registry model: [Fairchild SA227-AC](https://openairdocs.org/model/fairchild-sa227-ac) (registry code 3377509) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane - Serial number: AC682 - Year built: 1987 - Airframe hours: 23963 - Engines: Garrett TPE331 1000 horsepower turbo prop; Garrett TPE331 1000 horsepower turbo prop - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Pak West Airlines, doing business as Sierra West Airlines - Registered owner: Sierra West Airlines Inc - Airworthiness certificate: Standard, Normal - Last inspection: Continuous airworthiness, June 20, 2019 - Departed: ELP, El Paso, TX - Destination: ELP, El Paso, TX - Airport: ELP, El Paso Int'l, runway 26L, 9,025 × 150 ft, concrete - Equipment: Stall warning system, ADS-B, Angle of attack indicator, Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 36; injuries: none; flight instructor, airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review April 20, 2019; seat: left; restraint: 4-point; flight hours: 4,950 total, 3,900 in this make and model, 4,500 as pilot in command, 170 in the last 90 days, 51 in the last 30 days, 2 in the last 24 hours - Co-pilot; age 25; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review July 1, 2019; seat: right; restraint: 4-point; flight hours: 900 total, 800 as pilot in command, 14 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 90° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: 11,000 ft broken - Temperature: 79 °F, dew point 45 °F - Altimeter: 30.12 inHg - Observed at: ELP ## 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 20190727023539A](https://openairdocs.org/incident/20190727023539A), Jul 27, 2019: Fairchild SA227-AC, El Paso, TX, Substantial damage. On July 27,2019 at 05:35 MDT, a Fairchild SA227-C, registered to sierra west airlines, landed with the left landing gear up at El Paso international airport El… ## Docket (7 files) The files NTSB released with the investigation on April 3, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=99971. 8.3 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481941&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Pilot Statements (item 2, .PDF, 446 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481942&FileExtension=.PDF&FileName=Pilot%20Statements-Master.PDF - Airplane Photos (item 3, .PDF, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481943&FileExtension=.PDF&FileName=Airplane%20Photos-Master.PDF - Airplane Flight / Maintenance Log (item 4, .PDF, 817 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481944&FileExtension=.PDF&FileName=Airplane%20Flight%20%2F%20Maintenance%20Log-Master.PDF - Airplane Flight Manual (Excerpt) (item 5, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481945&FileExtension=.PDF&FileName=Airplane%20Flight%20Manual%20(Excerpt)-Master.PDF - Maintenance Manual (Excerpt) (item 6, .PDF, 2.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481946&FileExtension=.PDF&FileName=Maintenance%20Manual%20(Excerpt)-Master.PDF - FAA Airworthiness Directive 2000-17-11 (item 7, .PDF, 392 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481947&FileExtension=.PDF&FileName=FAA%20Airworthiness%20Directive%202000-17-11-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.