# NTSB CEN13LA116: Seguine Swift II, N84NS, San Antonio, TX, December 24, 2012 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: December 24, 2012, 10:15 local (16:15 UTC) - Place: San Antonio, TX - Coordinates: 29.570278, -98.46833 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=29.5703&lon=-98.4683&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Serious injuries - Injuries: 1 serious, 1 minor - Status: Completed, report December 11, 2013 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 85907 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN13LA116 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/85907/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=85907 - Page: https://openairdocs.org/ntsb/CEN13LA116 ## Probable cause The pilot's failure to attain a proper pitch attitude and airspeed during initial climb, which resulted in an aerodynamic stall. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: pitch control](https://openairdocs.org/ntsb-findings/01062022): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Seguine Bruce K SWIFT II, 1 case](https://openairdocs.org/ntsb-findings/01062022/cases.md?model=05606WJ), [All aircraft, 526 cases](https://openairdocs.org/ntsb-findings/01062022/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Seguine Bruce K SWIFT II, 1 case](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=05606WJ), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Performance/control parameters: angle of attack](https://openairdocs.org/ntsb-findings/01062042): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Seguine Bruce K SWIFT II, 1 case](https://openairdocs.org/ntsb-findings/01062042/cases.md?model=05606WJ), [All aircraft, 990 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md) - [Personnel issues](https://openairdocs.org/ntsb-findings/02040000): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Seguine Bruce K SWIFT II, 1 case](https://openairdocs.org/ntsb-findings/02040000/cases.md?model=05606WJ), [All aircraft, 56 cases](https://openairdocs.org/ntsb-findings/02040000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241); cases with it: [Seguine Bruce K SWIFT II, 1 case](https://openairdocs.org/ntsb-events/241/sequence.md?model=05606WJ), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Initial climb: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Seguine Bruce K SWIFT II, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=05606WJ), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Seguine Bruce K SWIFT II, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05606WJ), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The airplane was climbing through about 50 to 75 feet above ground level when it suddenly rolled left. The pilot tried to counteract the roll, but the airplane was unresponsive to control inputs. The sudden roll followed by a lack of control authority was consistent with an aerodynamic stall as the airplane transitioned from the aerodynamic effects of flight near the ground. A stall progression near the ailerons would have affected control authority. A postaccident examination of the flight control system revealed no malfunctions or failures that would have precluded normal operation. It is likely that the pilot climbed too steeply after takeoff without attaining the proper airspeed. ## Factual narrative On December 24, 2012, about 1015 central standard time, an experimental amateur-built Swift II, N84NS, impacted terrain following a loss of control after takeoff from Twin-Oaks Airport (T94), San Antonio, Texas. The airplane sustained substantial damage. The pilot sustained serious injuries and the pilot rated passenger sustain minor injuries. The airplane was registered to and operated by the pilot under 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed and a flight plan had not been filed for the local flight that was originating at the time of the accident. The pilot stated that during takeoff on runway 30 (2,225 feet by 30 feet, turf), he rotated the airplane about 75-80 knots. The airplane experienced a normal climb until reaching about 50-75 feet above ground level, when the airplane "suddenly" pitched left and was unresponsive to control inputs. The pilot tried to flare the airplane and reduce engine power "just before" the airplane impacted the ground. The airplane also impacted fences and a shed. According to a Federal Aviation Administration inspector, a witness stated that the airplane pitched up abnormally. The pilot had modified the wings, and the wing stall progression was from the wing tip to wing root. There was about 12 gallons of fuel in the left wing fuel. The pilot stated that he was unable to counteract the left roll. Examination of the airplane flight controls confirmed flight control continuity. ## Aircraft - Registration: [N84NS](https://openairdocs.org/aircraft/N84NS), registered now, S/N 01 (OpenAirDocs) - Reported make and model: Seguine Swift II - Registry model: [Seguine Bruce K SWIFT II](https://openairdocs.org/model/seguine-bruce-k-swift-ii) (registry code 05606WJ) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 01 - Engines: Lycoming IO-360-A3B6D 225 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Pilot - Registered owner: Pilot - Airworthiness certificate: Special, Experimental (Special) - Departed: T94, San Antonio, TX - Destination: T94, San Antonio, TX - Airport: T94, Twin-Oaks Airport, runway 30, 2,225 × 30 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: none; airline transport, private; airplane ratings: multi-engine land, single-engine land; instrument ratings: helicopter, airplane; medical: class 2, with waivers/limitations; last flight review August 20, 2012; seat: left; flight hours: 10,685 total, 20 in this make and model, 7,644 as pilot in command, 30 in the last 90 days, 2 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 50° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: 25,000 ft broken - Temperature: 61 °F, dew point 43 °F - Altimeter: 29.98 inHg - Observed at: SAT, 2 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 20121224028839A](https://openairdocs.org/incident/20121224028839A), Dec 24, 2012: Seguine Bruce K SWIFT II, San Antonio, TX, Destroyed. Aircraft rotated normally however pilot initiated a high angle of attack causing aircraft to loose lift due to low airflow over wings which resulted in loss of… ## Docket (2 files) The files NTSB released with the investigation on June 13, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=85907. 1.0 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 981 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40392349&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Record of Conversation - FAA (item 2, .PDF, 50 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40392350&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20FAA-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.