On August 2, 2009, about 1949 central daylight time, an experimental amateur-built Piontkowski Challenger, N4526G, operated by a private pilot, sustained substantial damage when the airplane struck a telephone line and then subsequently impacted the Kankakee River near Kankakee, Illinois. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of 14 CFR Part 91 without a flight plan. The pilot on board the airplane sustained serious injuries. The flight originated at the Greater Kankakee Airport (IKK), near Kankakee, Illinois.

According to witness statements in a Kankakee County Sheriff’s Police report, the aircraft was observed flying low along the Kankakee River. The IKK airport manager was a witness in a boat on the river. He recognized that the airplane was based at IKK. He saw that the airplane flew about 30 to 40 feet above the water. The airplane was further observed impacting a telephone line that went across the river and then impacting the Kankakee River.

First responders reported that the pilot had the smell of alcohol on his breath. The pilot had his blood drawn more than 3½ hours after the accident on August 2, 2009, about 2320 and taken into evidence by the Kankakee County Sheriff. The laboratory results reference the blood draw indicated 0.127 g/dL of ethanol.

Federal Aviation Administration (FAA) inspectors examined and took photographs of the wreckage. Their examination and review of their photographs did not reveal any pre-impact anomalies.

FAA regulation 91.17 Alcohol or drugs, in part, stated:

(a) No person may act or attempt to act as a crewmember of a civil aircraft - (1) Within 8 hours after the consumption of any alcoholic beverage; (2) While under the influence of alcohol; … or (4) While having an alcohol concentration of 0.04 or greater in a blood or breath specimen. Alcohol concentration means grams of alcohol per deciliter of blood or grams of alcohol per 210 liters of breath.

FAA regulation 91.119 Minimum safe altitudes: General, in part, stated:

Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes: ... (c) Over other than congested areas. An altitude of 500 feet above the surface, except over open water or sparsely populated areas. In those cases, the aircraft may not be operated closer than 500 feet to any person, vessel, vehicle, or structure.