# NTSB GAA18CA329: Dobbs George Coot, N100TN, Malone, WI, June 7, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: June 6, 2018, 19:00 local (Jun 7, 2018, 00:00 UTC) - Place: Malone, WI - Coordinates: 44.0475, -88.440277 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.0475&lon=-88.4403&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report March 18, 2019 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 97418 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA18CA329 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97418/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97418 - Page: https://openairdocs.org/ntsb/GAA18CA329 ## Probable cause The pilot’s improper decision to take off with a known structural issue, which resulted in hull damage. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Dobbs George COOT A, 1 case](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=05604TE), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Fuselage: fuselage main structure](https://openairdocs.org/ntsb-findings/01035310): Aircraft › Aircraft structures · Fatigue/wear/corrosion (probable cause); cases with it: [Dobbs George COOT A, 1 case](https://openairdocs.org/ntsb-findings/01035310/cases.md?model=05604TE), [All aircraft, 24 cases](https://openairdocs.org/ntsb-findings/01035310/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event); cases with it: [Dobbs George COOT A, 1 case](https://openairdocs.org/ntsb-events/900/sequence.md?model=05604TE), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) - [Takeoff: Aircraft structural failure](https://openairdocs.org/ntsb-events/337); cases with it: [Dobbs George COOT A, 1 case](https://openairdocs.org/ntsb-events/337/sequence.md?model=05604TE), [All aircraft, 290 cases](https://openairdocs.org/ntsb-events/337/sequence.md) ## Analysis According to the pilot in the experimental amateur-built amphibious airplane, during takeoff from a lake, the airplane bounced twice, but on the third bounce, the hull "gave way." Water entered the airplane, and the pilot exited through the canopy. The pilot reported that the hull had been repaired previously, but it still had "some leakage" after the repair. Substantial damage was sustained to the forward left side of the hull where the sponson was attached. Photographs provided by the Federal Aviation Administration showed long-term water damage to the plywood and fiberglass hull structure. ## Factual narrative According to the pilot in the experimental amateur-built amphibious airplane, during takeoff on a lake the airplane bounced twice, but on the third bounce the hull "gave way." The airplane took on water and the pilot exited through the canopy. The hull failure occurred to the front left side where the sponson was attached. The pilot reported that the hull had been repaired previously, but it still had "some leakage" after the repair. Substantial damage was sustained to the forward left side of the hull. Photographs provided by the FAA showed long-term water damage to the plywood and fiberglass hull structure. ## Aircraft - Registration: [N100TN](https://openairdocs.org/aircraft/N100TN), registered now, S/N SS22, built 1980 (OpenAirDocs) - Reported make and model: DOBBS GEORGE COOT (A) - Registry model: [Dobbs George COOT A](https://openairdocs.org/model/dobbs-george-coot-a) (registry code 05604TE) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: SS22 - Year built: 1980 - Airframe hours: 538 - Engines: Lycoming O-320-A2B 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, October 25, 2017 - Departed: Malone, WI - Destination: Cheboygan, MI - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; injuries: none; private; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: basicmed; last flight review March 23, 2017; seat: left; restraint: none; flight hours: 905.9 total, 12.8 in this make and model, 905.9 as pilot in command, 12 in the last 90 days, 6 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 72 °F, dew point 55 °F - Altimeter: 29.87 inHg - Observed at: KFLD, 17 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 20180606007209A](https://openairdocs.org/incident/20180606007209A), Jun 6, 2018: Dobbs George COOT A, Pipe, WI, Substantial damage. On 06/06/2018, N100TN landed on lake winnebago near Pipe, WI. And taxied to the shoreline at 1830 CST. The aircraft taxied out for take-off. On take-off, the… ## Docket (2 files) The files NTSB released with the investigation on October 31, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97418. 608 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 358 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40467885&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Photos (item 2, .PDF, 2 photos, 249 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40467886&FileExtension=.PDF&FileName=Photos-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.