# NTSB GAA19CA234: Cessna T310, N358MN, Philadelphia, PA, March 24, 2019 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: March 24, 2019, 15:30 local (19:30 UTC) - Place: Philadelphia, PA - Coordinates: 40.087501, -75.005554 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.0875&lon=-75.0056&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Landing gear not configured](https://openairdocs.org/ntsb-events/095) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed, report November 6, 2019 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 99347 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA19CA234 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/99347/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=99347 - Page: https://openairdocs.org/ntsb/GAA19CA234 ## Probable cause The pilot’s and flight instructor's failure to verify that the landing gear were extended, which resulted in a gear-up landing. Contributing to the accident was the flight instructor’s inadvertent pulling of the landing gear motor circuit, which prevented the landing gear from extending. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: task monitoring/vigilance](https://openairdocs.org/ntsb-findings/02021520): Personnel issues › Psychological · Student/instructed pilot (probable cause); cases with it: [Cessna T310R, 2 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md?model=2074246), [All aircraft, 330 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md) - [Attention/monitoring: task monitoring/vigilance](https://openairdocs.org/ntsb-findings/02021520): Personnel issues › Psychological · Instructor/check pilot (probable cause); cases with it: [Cessna T310R, 2 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md?model=2074246), [All aircraft, 330 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md) - [Landing gear system: gear extension and retract sys](https://openairdocs.org/ntsb-findings/01023230): Aircraft › Aircraft systems · Not used/operated (probable cause); cases with it: [Cessna T310R, 3 cases](https://openairdocs.org/ntsb-findings/01023230/cases.md?model=2074246), [All aircraft, 416 cases](https://openairdocs.org/ntsb-findings/01023230/cases.md) - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Instructor/check pilot (probable cause); cases with it: [Cessna T310R, 1 case](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=2074246), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) - [Landing gear system](https://openairdocs.org/ntsb-findings/01023200): Aircraft › Aircraft systems · Unintentional use/operation (probable cause); cases with it: [Cessna T310R, 1 case](https://openairdocs.org/ntsb-findings/01023200/cases.md?model=2074246), [All aircraft, 113 cases](https://openairdocs.org/ntsb-findings/01023200/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Landing gear not configured](https://openairdocs.org/ntsb-events/095) (defining event); cases with it: [Cessna T310R, 2 cases](https://openairdocs.org/ntsb-events/095/sequence.md?model=2074246), [All aircraft, 584 cases](https://openairdocs.org/ntsb-events/095/sequence.md) ## Analysis The flight instructor in the retractable-landing gear, multiengine airplane reported that, while performing aerial survey training for a newly hired pilot, the airplane was slowed to the mission airspeed of 117 knots, which meant reduced power and the use of more than 15° of flaps. He added that he then pulled the landing gear warning circuit breaker to silence the landing gear warning horn to ensure clear communication but that he did not pull the landing gear motor circuit breaker. The pilot receiving instruction reported that he did not know that the instructor had pulled the landing gear warning circuit breaker. The instructor further reported that, while returning to the departure airport, the landing checklist was "accomplished" 15 to 20 miles from the airport. He saw that the pilot was "falling behind on power and descent management" and that the airplane was high and fast for the approach. The instructor advised the pilot to correct but then began to assist the pilot when it "was taking longer [than anticipated.]" The airplane decelerated into the white airspeed arc, and the instructor moved the landing gear selector switch into the down position and added full flaps. He added that, because the flaps were added shortly after the landing gear selector switch was put into the down position, he could not tell by the flight characteristics that the landing gear had not extended. Neither he nor the pilot noticed that there was no green down-and-locked position light indicator. The airplane landed with the landing gear retracted. The airplane sustained substantial damage to the fuselage and both engines. The instructor added that, while configuring the airplane on the runway, he observed that the landing gear warning horn and landing gear motor circuit breakers were tripped. The director of maintenance reported that, during a postaccident examination, the airplane was lifted onto jacks and an emergency gear extension and three electrical landing gear retractions were conducted, and no defects were found. In a photograph provided by the flight instructor, the landing gear warning horn and landing gear motor circuit breakers are right next to each other. Despite the instructor's statement that he did not pull the landing gear motor switch, given the proximity of the breakers to each other, it is likely that the pilot inadvertently pulled the landing gear motor switch when he pulled the landing gear warning horn switch, which prevented the gear from extending. The airplane manufacturer's Pilot's Operating Handbook contained a note in the section titled, "Landing Gear Warning Horn," which states, Do not pull landing gear warning circuit breaker to silence horn as this turns off the landing gear control relay, thus the landing gear cannot be retracted. ## Factual narrative The flight instructor in the retractable landing gear, multi-engine airplane reported that, while performing aerial survey training for a newly hired pilot, the airplane was slowed to the mission airspeed of 117 knots, which meant reduced power and the use of more than 15° of flaps. He then pulled the circuit breaker to silence the landing gear warning horn to ensure clear communication, but did not pull the landing gear motor circuit breaker. The pilot receiving instruction reported that he did not know that the instructor had pulled the circuit breaker. The flight instructor further reported that, while returning to the departure airport, the landing checklist was "accomplished" 15 to 20 miles from the airport. He observed that the pilot was "falling behind on power and descent management" and the airplane was high and fast for the approach. The instructor advised the pilot to correct but then began to assist the pilot when it "was taking longer [than anticipated.]" The airplane decelerated into the white airspeed arc, and the instructor moved the landing gear selector switch into the down position and added full flaps. He added that, since the flaps were added shortly after the landing gear selector switch was put into the down position, he could not tell by the flight characteristics that the landing gear had not extended. Neither he nor the pilot observed that there was no green down and locked position light indicator. The airplane landed with the landing gear retracted. The flight instructor added that, while configuring the airplane on the runway, he observed that the landing gear warning horn and landing gear motor circuit breakers were tripped. The airplane sustained substantial damage to the fuselage and both engines. The director of maintenance reported that, during a postaccident examination, they lifted the airplane onto jacks and performed an emergency gear extension. He added that they then did three electrical landing gear retractions and no defects were found. In a photo provided by the flight instructor, the landing gear warning horn and landing gear motor circuit breakers are immediately next to each other. The airplane manufacturer pilot operating handbook contains a note in section titled "Landing Gear Warning Horn", which states, Do not pull landing gear warning circuit breaker to silence horn as this turns off the landing gear control relay, thus the landing gear cannot be retracted. ## Aircraft - Registration: [N358MN](https://openairdocs.org/aircraft/N358MN), registered now, S/N 310R0881 (OpenAirDocs) - Reported make and model: Cessna T310 (R) - Registry model: [Cessna T310R](https://openairdocs.org/model/cessna-t310r) (registry code 2074246) (OpenAirDocs) - Category: Airplane - Serial number: 310R0881 - Year built: 1976 - Airframe hours: 7124.8 - Engines: Continental TSIO-520-EB 300 horsepower reciprocating; Continental TSIO-520-EB 300 horsepower reciprocating - Damage: Substantial damage - Flight: Other work use, Part 91 - Operator: Keystone Aerial Surveys Inc - Registered owner: Keystone Aerial Surveys Inc - Airworthiness certificate: Standard, Normal - Last inspection: Annual, December 6, 2018 - Departed: FRG, Farmingdale, NY - Destination: PNE, Philadelphia, PA - Airport: PNE, Northeast Philadelphia, runway 24, 7,000 × 150 ft, asphalt - Equipment: Electronic flight bag or handheld device, Stall warning system, Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; last flight review March 27, 2018; seat: right; restraint: 3-point; flight hours: 7,636 total, 3,800 in this make and model, 7,611 as pilot in command, 54 in the last 90 days, 35 in the last 30 days - Pilot; age 26; injuries: none; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review February 25, 2018; seat: left; restraint: 3-point; flight hours: 849 total, 12 in this make and model, 704 as pilot in command, 14 in the last 90 days, 14 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 12 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 63 °F, dew point 19 °F - Altimeter: 30.09 inHg - Observed at: KPNE, 1 nm away ## 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 20190324001919A](https://openairdocs.org/incident/20190324001919A), Mar 24, 2019: Cessna T310R, Philadelphia, PA, Substantial damage. On March 24, 2019, about 15:30 eastern standard time (EST), Cessna T310R, N358MN, was substantially damaged during the landing roll at northeast Philadelphia… ## Docket (6 files) The files NTSB released with the investigation on June 27, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=99347. 6.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 5.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40473851&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Conversation - Flight Instructor (item 2, .PDF, 68 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40473852&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20Flight%20Instructor-Master.PDF - Pilot's Statement (item 3, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40473853&FileExtension=.PDF&FileName=Pilot%27s%20Statement-Master.PDF - Record of Conversation - Director of Maintenance (item 4, .PDF, 68 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40473854&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20Director%20of%20Maintenance-Master.PDF - POH excerpt (item 5, .PDF, 91 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40473855&FileExtension=.PDF&FileName=POH%20excerpt-Master.PDF - Accident Photos (item 6, .PDF, 2 photos, 804 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40473856&FileExtension=.PDF&FileName=Accident%20Photos-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.