# NTSB LAX08LA103: Artic S-1B2, N73WY, Rock River, WY, April 14, 2008 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: April 14, 2008, 10:38 local (16:38 UTC) - Place: Rock River, WY - Coordinates: 41.887779, -105.931388 - Nearby events: https://openairdocs.org/map.md?lat=41.8878&lon=-105.9314&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Serious injuries - Injuries: 1 serious, 1 minor - Status: Completed, report May 28, 2008 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 67819 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX08LA103 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67819/pdf - Page: https://openairdocs.org/ntsb/LAX08LA103 ## Probable cause The pilot's failure to maintain an adequate airspeed while maneuvering that led to an inadvertent stall. A contributing factor in the accident was the low altitude of the flight that reduced the time available for recovery from an upset. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Arctic S-1B2, 2 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=0790208), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Arctic S-1B2, 2 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=0790208), [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: [Arctic S-1B2, 2 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=0790208), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot made consistent statements to various law enforcement, medical response personnel, and the company that he has no memory of the accident sequence. The flight was for the purpose of transporting a State of Wyoming biologist along various watershed features in order to take a census of geese. The biologist said they had been flying about 100 feet agl following a creek over low rolling terrain while he observed and counted the geese. On previous flights, the pilot had flown too fast for the biologist to accurately count the birds of interest and he asked the pilot to fly slower. On this flight, the pilot extended the flaps and was flying slower than on previous flights at a speed he estimated at 50 to 60 miles per hour. They were following the creek and the pilot was in a turn to the right and then he began a turn back to the left. The biologist was looking away when he then heard the pilot call out an expletive. When he looked forward, the airplane was in a right wing and nose down attitude descending toward the ground. The pilot managed to level the airplane out just before ground impact. The biologist said he did not hear a change in the engine sounds during the sequence and had not heard the pilot voice any concerns about the way the airplane was handling. ## Factual narrative On April 14, 2008, about 1038 mountain daylight time, an Artic Aircraft Corporation S-1B2 single engine airplane, N73WY, collided with terrain while maneuvering at low altitude near Rock River, Wyoming. The aircraft was owned and operated by TS Aviation, Worland, Wyoming, and was being used for survey of geese for the Wyoming Department of Game and Fish at the time of the accident. According to the Director of Operations for the company, TS Aviation does not have a 90-day exclusive use contract with the State of Wyoming, and was operating the aircraft under the provisions of 14 CFR Part 91 of the Federal Aviation Regulations and not as a public-use operation. The airplane sustained substantial damage. The certificated commercial pilot incurred serious injuries while the passenger, a biologist employed by the Wyoming Department of Game and Fish, sustained minor injuries. Visual meteorological conditions prevailed and a company flight plan was filed. The flight departed Worland at an undetermined time for the survey mission. The pilot made consistent statements to various law enforcement, medical response personnel, and the company that he has no memory of the accident sequence. The biologist was interviewed by a Federal Aviation Administration inspector, and he submitted a written statement. The biologist said they had been flying about 100 feet agl following a creek over low rolling terrain while he observed and took a census of the geese population. On previous flights, the pilot had flown too fast for the biologist to accurately count the birds of interest and he asked the pilot to fly slower. On this flight, the pilot extended the flaps and was flying slower than on previous flights at a speed he estimated at 50 to 60 miles per hour. They were following the creek and the pilot was in a turn to the right and then he turned back to the left. The biologist was looking away when he then heard the pilot call out an expletive. When he looked forward, the airplane was in a right wing and nose down attitude descending toward the ground. The pilot managed to level the airplane out just before ground impact. The biologist said he did not hear a change in the engine sounds during the sequence and had not heard the pilot voice any concerns about the way the airplane was handling. ## Aircraft - Registration: [N73WY](https://openairdocs.org/deregistered/N73WY-2010-12-08), registration cancelled 2010-12-08, S/N 1028 (OpenAirDocs) - Reported make and model: Artic Aircraft Corp. S-1B2 - Registry model: [Arctic S-1B2](https://openairdocs.org/model/arctic-s-1b2) (registry code 0790208) (OpenAirDocs) - Category: Airplane - Serial number: 1028 - Airframe hours: 7868 - Engines: Lycoming O-320-B2B 160 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial observation, Part 91 - Airworthiness certificate: Standard, Normal; Standard, Utility - Last inspection: 100 hour, April 1, 2008, 29 hours before - Departed: LAR, Laramie, WY - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 29; injuries: serious; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2; seat: front; flight hours: 5,239 total, 3,592 in this make and model, 5,219 as pilot in command, 215 in the last 90 days, 108 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 220° at 17 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 54 °F, dew point 23 °F - Altimeter: 30.12 inHg - Observed at: KLAR, 30 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 20080414831849A](https://openairdocs.org/incident/20080414831849A), Apr 14, 2008: Arctic S1B2, Rock River, WY, Substantial damage. (-23) Aircraft was at low level, flight maneuvering. Pilot made left turn, stalled and impacted ground. 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.