# NTSB CHI99LA259: Cessna 180, N4636B, Tower, MN, July 18, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 17, 1999, 19:30 local (Jul 18, 1999, 00:30 UTC) - Place: Tower, MN - Coordinates: 47.80978, -92.289436 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.8098&lon=-92.2894&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 21, 2002 - Report: Approved by Office Director - Parties: FAA - NTSB case key (mKey): 46902 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI99LA259 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/46902/pdf - Page: https://openairdocs.org/ntsb/CHI99LA259 ## Probable cause failure of the operator of the boat to maintain clearance with the floatplane. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - On ground/water collision with object, landing - clearance - not maintained, driver of vehicle (cause) ## Analysis The seaplane was struck by a powerboat shortly after the plane landed on the lake. A private pilot witness said the boat was on the right side of the aircraft travelling 35-40 mph. The witness said the boat turned at the last moment and hit the right float of the plane. ## Factual narrative On July 17, 1999, at 1930 central daylight time, a Cessna 180, N4636B, piloted by a private pilot, was substantially damaged shortly after it landed when it was struck by a power boat. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 personal flight was not operating on a flight plan. The pilot reported no injuries. The flight departed Tower, Minnesota, exact time unknown. According to the pilot, he had just landed the airplane on Vermillion Lake. He said he did not see the power boat approaching from his right side until a few moments before it struck his airplane's right float. A witness said the boat was travelling about 35 to 40 miles per hour as it rounded a bend in the lake and headed toward the boat. The witness said the boat did not turn until a few moments before the collision. The pilot said he tried to turn the airplane out of the boat's path. He said the airplane began a slow turn to its left just as the boat collided with its float. The pilot estimated the boat's speed was about 40 to 50 miles per hour. ## Aircraft - Registration: [N4636B](https://openairdocs.org/aircraft/N4636B), registered now, S/N 31534, built 1955 (OpenAirDocs) - Reported make and model: Cessna 180 - Registry model: [Cessna 180](https://openairdocs.org/model/cessna-180) (registry code 2072602) (OpenAirDocs) - Registry engine: [Continental O-470 series](https://openairdocs.org/engine/continental-o-470-series) (registry code 17026, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 31534 - Airframe hours: 3836 - Engines: Teledyne Cont O-470 230 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: 36-Bravo, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 12, 1999, 2 hours before - Departed: Tower, MN - Destination: TOWER, MN - Airport: Vermillion Lake ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; injuries: none; private; airplane ratings: single-engine sea, single-engine land; medical: class 3, with waivers/limitations; seat: left; flight hours: 404 total, 251 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 0° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 68 °F, dew point 61 °F - Altimeter: 30.09 inHg - Observed at: CQM ## 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 19990717009579A](https://openairdocs.org/incident/19990717009579A), Jul 17, 1999: Cessna 180, Tower, MN, Substantial damage. (Tty) landing on lake, acft hit a boat. (.19) on July 17, 1999, at 1930 central daylight time, a Cessna 180, N4636B, piloted by a private pilot, was… ## Other investigations on N4636B (1) 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. - [NTSB CHI91LA180](https://openairdocs.org/ntsb/CHI91LA180), Jun 16, 1991: Cessna 180 (N4636B), Orr, MN, substantial damage. Probable cause: BECAUSE OF INADEQUATE COMPENSATION FOR THE WIND CONDITIONS, AIRCRAFT CONTROL WAS LOST BY THE PILOT. A FACTOR RELATED TO THE ACCIDENT WAS A GUSTY CROSSWIND LANDING ENVIRONMENT. 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.