# NTSB CHI99LA318: Aeronca 11BC, N9404E, Watervliet, MI, August 28, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 27, 1999, 20:15 local (Aug 28, 1999, 00:15 UTC) - Place: Watervliet, MI - Coordinates: 42.179012, -86.250411 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=42.1790&lon=-86.2504&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report June 21, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 47247 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI99LA318 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/47247/pdf - Page: https://openairdocs.org/ntsb/CHI99LA318 ## Probable cause the pilot not maintaining aircraft control during takeoff, and the pilot not correcting for the porpoise. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - on ground/water, takeoff - roll/run - aircraft control - not maintained, pilot in command (cause) - porpoise/pilot-induced oscillation - not corrected, pilot in command (cause) - In flight collision with terrain/water, takeoff - Gear collapsed, takeoff - landing gear - overload ## Analysis The pilot said that during takeoff, the airplane bounced 2-3 times on the runway, and then the landing gear and propeller broke. The passenger on board the airplane stated that 'upon liftoff, the airplane ballooned off of the runway. We came back down and bounced once, kind of porpoised twice, and came back down, and the landing gear collapsed.' Examination of the airplane revealed no anomalies. ## Factual narrative On August 27, 1999, at 2015 eastern daylight time (edt), an Aeronca 11BC, N9404E, operated by a private pilot sustained substantial damage when on takeoff from runway 02 (2,600 feet by 200 feet, dry grass/turf) at the Watervliet Municipal Airport, Watervliet, Michigan, the airplane bounced, porpoised, and impacted on the runway. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under 14 CFR Part 91. No flight plan was on file. The pilot and passenger on board the airplane reported no injuries. The local flight was originating at the time of the accident. In his written statement, the pilot said that during takeoff, the airplane bounced 2-3 times on the runway, and then the landing gear and propeller broke. The passenger on board the airplane stated that "upon liftoff, the airplane ballooned off of the runway. We came back down and bounced once, kind of porpoised twice, and came back down, and the landing gear collapsed." A Federal Aviation Administration (FAA) inspector examined the airplane at the Watervliet Municipal Airport. The airplane's main landing gear was folded rearward underneath the airplane's fuselage. Both main gear struts were broken aft from the landing gear box, just behind the airplane's firewall. The lower portion of the firewall was bent aft. The bottom forward fuselage skin was crushed upward. The airplane's wood propeller was broken and splintered. Flight control continuity was confirmed. Examination of the airplane's engine, engine controls, and other airplane systems revealed no anomalies. ## Aircraft - Registration: [N9404E](https://openairdocs.org/aircraft/N9404E), registered now, S/N 11AC-1041, built 1946 (OpenAirDocs) - Reported make and model: Aeronca 11BC - Registry model: [Aeronca 11AC](https://openairdocs.org/model/aeronca-11ac) (registry code 0191102) (OpenAirDocs) - Registry engine: [Continental A&C65 series](https://openairdocs.org/engine/continental-a-c65-series) (registry code 17003, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1041 - Airframe hours: 2559 - Engines: Continental A-65-8 65 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Vagabond Club - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 18, 1999, 21 hours before - Departed: 40C - Airport: 40C, Watervliet Municipal, runway 2, 2,600 × 200 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: right; flight hours: 200 total, 19 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 0° at 4 knots - Visibility: 6 statute miles - Lowest ceiling: none - Temperature: 72 °F, dew point 66 °F - Altimeter: 29.00 inHg - Observed at: BEH, 9 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 19990827026279A](https://openairdocs.org/incident/19990827026279A), Aug 27, 1999: Bbavia 11AC, Watervliet, MI, Substantial damage. (.19) On August 27, 1999, at 2015 eastern daylight time (EDT), an Aeronca 11BC, N9404E, operated by a private pilot sustained substantial damage when on… ## Other investigations on N9404E (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 GAA17CA347](https://openairdocs.org/ntsb/GAA17CA347), Jun 16, 2017: Aeronca 11AC (N9404E), Watervliet, MI, substantial damage. Probable cause: The flight instructor's inadequate preflight planning, which resulted in a takeoff over maximum gross weight from a turf runway in high density altitude conditions and the airplane’s inability to… 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.