# NTSB CEN13LA374: Aviat A-1B, N715SB, Ely, MN, June 25, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: June 25, 2013, 13:00 local (18:00 UTC) - Place: Ely, MN - Coordinates: 47.913887, -91.877777 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.9139&lon=-91.8778&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report December 2, 2013 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - Minneapolis FSDO, Wipaire Inc. - NTSB case key (mKey): 87311 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN13LA374 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/87311/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=87311 - Page: https://openairdocs.org/ntsb/CEN13LA374 ## Probable cause The pilot’s failure to maintain control of the amphibious airplane during the water landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Aviat A-1B, 21 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=2210406), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Aviat A-1B, 33 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=2210406), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Landing gear system](https://openairdocs.org/ntsb-findings/01023200): Aircraft › Aircraft systems · Capability exceeded (probable cause); cases with it: [Aviat A-1B, 1 case](https://openairdocs.org/ntsb-findings/01023200/cases.md?model=2210406), [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: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Aviat A-1B, 24 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=2210406), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Landing: Dragged wing/rotor/float/other](https://openairdocs.org/ntsb-events/093); cases with it: [Aviat A-1B, 6 cases](https://openairdocs.org/ntsb-events/093/sequence.md?model=2210406), [All aircraft, 319 cases](https://openairdocs.org/ntsb-events/093/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Aviat A-1B, 23 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2210406), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot reported that the accident occurred when he was making water landings in the amphibious airplane. He stated that he noted no anomalies during his first landing. He said the lake surface had “light ripples,” and the wind speed was less than 5 knots. The pilot stated that his second landing approach and touchdown were also initially uneventful; however, shortly after the airplane touched down, it began to roll and yaw toward the left, and the left wing contacted the water. The airplane came to rest partially submerged, nose-low, in the lake. An examination of the recovered wreckage revealed substantial damage to several float struts and spreader bars; however, all examined component damage was consistent with overstress, with no preexisting material defects observed. Because the damage to the amphibious float components occurred during the accident, they likely did not contribute to the initial loss of control. Therefore, given the pilot's report of light wind, the pilot should have been able to maintain airplane control throughout the water landing. ## Factual narrative On June 25, 2013, at 1300 central daylight time, an Aviat Aircraft model A-1B amphibious airplane, N715SB, was substantially damaged during a water landing on Shagawa Lake, near Ely, Minnesota. The airline transport pilot and his passenger were not injured. The airplane was registered to and operated by a private individual, under the provisions of 14 Code of Federal Regulations Part 91, without a flight plan. Day visual meteorological conditions prevailed for the pleasure flight that departed Ely Municipal Airport (KELO), near Ely, Minnesota, about 1245. The pilot reported that after a short local area flight he began to make water takeoff-and-landings on Shagawa Lake toward the southeast. The pilot reported that his first landing was uneventful and that there were no anomalies with the airplane. He described the lake surface condition as having “light ripples” with a wind speed of less than 5 knots. He stated that his second landing approach and touchdown were again uneventful; however, shortly after the touchdown the airplane began to roll and yaw toward the left until the left wing made contact with the water. The airplane ultimately came to rest partially submerged nose-low in the lake. The fuselage, wings, and amphibious floats were damaged during the accident sequence. An examination of the recovered wreckage was completed by Federal Aviation Administration (FAA) inspectors and an aerospace engineer employed by the amphibious float manufacturer. Their examination revealed substantial damage to several float struts and spreader bars. The left rear float strut attachment fitting with fractured portions of lower airframe longeron tube and the inboard sections of the left and right rear spreader bar mounting tubes were submitted to the National Transportation Safety Board (NTSB) Materials Laboratory for additional examination. The examined components exhibited fracture features that were consistent with overstress. Additionally, no preexisting material defects were noted during the NTSB laboratory examination. The nearest aviation weather reporting station was located at Ely Municipal Airport (KELO), Ely, Minnesota, about 6.25 miles south of the accident site. At 1252, the KELO automated surface observing system reported: wind from 200 degrees at 4 knots, visibility 10 miles, sky clear, temperature 28 degrees Celsius, dew point 12 degrees Celsius, and an altimeter setting of 29.82 inches of mercury. ## Aircraft - Registration: [N715SB](https://openairdocs.org/aircraft/N715SB), registered now, S/N 2051 (OpenAirDocs) - Reported make and model: Aviat Aircraft, Inc. A-1B - Registry model: [Aviat A-1B](https://openairdocs.org/model/aviat-a-1b) (registry code 2210406) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 2051 - Airframe hours: 688 - Engines: Lycoming O-360-A1P 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 16, 2013 - Departed: KELO, Ely, MN - Destination: KELO, Ely, MN - Airport: Shagawa Lake ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; injuries: none; flight engineer, airline transport; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review May 5, 2013; seat: front; flight hours: 17,000 total, 40 in this make and model, 15,000 as pilot in command, 200 in the last 90 days, 69 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 200° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 54 °F - Altimeter: 29.81 inHg - Observed at: KELO, 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 20130625011479A](https://openairdocs.org/incident/20130625011479A), Jun 25, 2013: Aviat Aircraft Inc A-1B, Ely, MN, Substantial damage. Pilot departed the Ely, MN airport (elo) on a sightseeing flight with his wife. He decided to conduct a few practice landings on shagwa lake, just north of… ## Docket (4 files) The files NTSB released with the investigation on September 5, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=87311. 1.4 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 626 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40397821&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Memorandum of Conversation (Timothy E. Breuhl) (item 2, .PDF, 122 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40397822&FileExtension=.PDF&FileName=Memorandum%20of%20Conversation%20(Timothy%20E.%20Breuhl)-Master.PDF - NTSB Materials Laboratory Examination Summary (item 3, .PDF, 534 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40397823&FileExtension=.PDF&FileName=NTSB%20Materials%20Laboratory%20Examination%20Summary-Master.PDF - Weather Information (item 4, .PDF, 97 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40397824&FileExtension=.PDF&FileName=Weather%20Information-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.