# NTSB CEN12LA204: Piper PA-30, N373JT, Roanoke, TX, March 2, 2012 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: March 2, 2012, 14:20 local (20:20 UTC) - Place: Roanoke, TX - Coordinates: 33.04972, -97.232223 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.0497&lon=-97.2322&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Landing gear collapse](https://openairdocs.org/ntsb-events/094) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report August 29, 2013 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 83221 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN12LA204 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/83221/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=83221 - Page: https://openairdocs.org/ntsb/CEN12LA204 ## Probable cause The pilot’s failure to follow the published emergency procedures to lower the landing gear following a loss of electrical power. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Electrical power system: dC generation system](https://openairdocs.org/ntsb-findings/01022430): Aircraft › Aircraft systems · Failure; cases with it: [Piper PA-30, 1 case](https://openairdocs.org/ntsb-findings/01022430/cases.md?model=7103002), [All aircraft, 6 cases](https://openairdocs.org/ntsb-findings/01022430/cases.md) - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Piper PA-30, 13 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=7103002), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-flare/touchdown: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event); cases with it: [Piper PA-30, 20 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=7103002), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The pilot said he was on a cross-country flight and he noticed that the alternators were producing about 9 volts. He tried to troubleshoot the problem, and he switched the alternators off and on a “number” of times, but he was unable to get them to indicate more than 8 to 9 volts (the pilot used the term "alternator" and "generator" interchangeably in his statement). He said that he heard a “squeal” coming through the headset, and when the right alternator was switched off, the noise would stop. He said that he eventually lost radio communication capability while en route to his destination, and he diverted to an alternate airport. The pilot lowered the landing gear on the downwind leg, and he observed that the nose landing gear was extended by its reflection in the spinner. The landing roll was “normal” until the right main landing gear collapsed, and then the left main landing gear collapsed. A postaccident examination of the landing gear did not disclose any evidence of a mechanical malfunction. The pilot reported that he lost all electrical power due to a loss of one or both alternators. It is likely that the right alternator failed, so when the pilot turned off the right failed alternator, the noise stopped; however, the left alternator could not put out enough voltage to power the radios and other electrical demands. By the time the gear was lowered, there was not enough power to lock the left and right main landing gears in place, so they both collapsed during the landing roll. Had the pilot realized that he had lost electrical power and followed the emergency checklist, he could have verified the locked status of the landing gear and followed the emergency landing gear procedures to extend the gear. ## Factual narrative On March 2, 2012, about 1420 central standard time, a Piper PA-30, N373JT, had its main landing gear collapse during landing on runway 36 at the Northwest Regional Airport (52F), near Roanoke, Texas. The private pilot, who was the sole occupant, reported no injuries. The airplane sustained substantial spar damage. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Day visual flight rules (VFR) conditions prevailed for the flight, which did not operate on a VFR flight plan. The flight originated from the Crystal City Municipal Airport, near Crystal City, Texas, about 1300, and was destined for the Denton Municipal Airport (DTO), near Denton, Texas, when it diverted to 52F with electrical system issues. According to a pilot statement, during the flight the alternators were producing approximately nine volts of output. He switched the generators off and on a “number” of times and was unable to get them to get them to indicate more than eight to nine volts. The pilot had intermittent global positioning system operation, heard a “squeal” in his radio. He observed that when the right alternator was switched off, the noise would stop. The pilot eventually lost radio communication capability while en-route to DTO. He diverted to 52F and lowered the landing gear on downwind. The pilot observed that the nose landing gear was extended by its reflection in the spinner. The landing roll out was “normal” until the right main landing gear collapsed. The left main landing gear then collapsed. The pilot’s comments, in part, stated: It is obvious that at least one alternator failed, probably the right one, and the other alternator could not put out enough voltage to carry the radios, GPS, autopilot, lights and other electrical demands and by the time that gear was lowered there was not enough power in the battery to lock the gear in place and/or the gear failed to lock in place. The PA-30 flight manual contained an emergency procedure referencing emergency landing gear extension. As part of the procedure, the pilot is instructed to slow the airplane to an airspeed “not to exceed 100 mph.” The full travel of the extension handle or a green light on the instrument panel indicate the landing gear is extended. An operational note indicated that “reducing power and rocking gear extension handle will aid in manually extending the landing gear.” According to a Federal Aviation Administration inspector, there was no evidence of mechanical malfunctions or failures that would have precluded normal landing gear operation. ## Aircraft - Registration: [N373JT](https://openairdocs.org/deregistered/N373JT-2015-03-23), registration cancelled 2015-03-23, S/N 30-850, built 1965 (OpenAirDocs) - Reported make and model: PIPER PA-30 - Registry model: [Piper PA-30](https://openairdocs.org/model/piper-pa-30) (registry code 7103002) (OpenAirDocs) - Registry engine: [Lycoming IO-320 series](https://openairdocs.org/engine/lycoming-io-320-series) (registry code 41509, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 30-850 - Engines: LYCOMING IO-320 SERIES 150 horsepower reciprocating; LYCOMING IO-320 SERIES 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Departed: 20R, CRYSTAL CITY, TX - Destination: DTO, Denton, TX - Flight plan: VFR - Airport: 52F, Northwest Regional Airport, runway 36, 3,500 × 40 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 78; injuries: none; private; airplane ratings: multi-engine land; medical: class 3; seat: left; flight hours: 12,000 total, 12,000 as pilot in command, 40 in the last 90 days, 15 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 360° at 12 knots, gusting 17 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 64 °F, dew point 39 °F - Altimeter: 29.79 inHg - Observed at: AFW, 6 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 20120302003679A](https://openairdocs.org/incident/20120302003679A), Mar 2, 2012: Piper PA-30, Roanoke, TX, Minor damage. 3/2/12: Responded to a call from the airport manager of 52F regarding an aircraft that had just landed gear up on the runway. Arrived on scene as iic at 15:15… ## Docket (4 files) The files NTSB released with the investigation on February 4, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=83221. 1.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 824 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40372425&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot Statement (item 2, .PDF, 112 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40372424&FileExtension=.PDF&FileName=Pilot%20Statement-Master.PDF - Miscellaneous - Communication Summary (item 3, .PDF, 56 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40384336&FileExtension=.PDF&FileName=Miscellaneous%20-%20Communication%20Summary-Master.PDF - Miscellaneous - Piper PA-30 POH Excerpt (item 4, .PDF, 116 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40384334&FileExtension=.PDF&FileName=Miscellaneous%20-%20Piper%20PA-30%20POH%20Excerpt-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.