On July 4, 2009, about 1300 central daylight time, a Consolidated Aeronautics, Lake LA-4-200, N56LA, piloted by a private pilot, sustained substantial damage during a water landing on Lake Michigan, near Racine, Wisconsin. During the landing, the left sponson separated from the airplane. The 14 CFR Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The pilot was not injured. The departure time and location were not determined. The pilot initially reported to Federal Aviation Administration inspectors that the airplane's sponson struck a submerged object during landing. The FAA inspector that examined the airplane after the accident relayed in a telephone interview that there was no evidence that the sponson had impacted anything during the accident. No pre-existing anomalies were found with respect to the airplane, sponson, or sponson attachment. The pilot did not respond to further requests for information by the National Transportation Safety Board's investigator.