On August 20, 2017, about 1345 eastern daylight time, a Piper J3C-65, N46286, was substantially damaged during a forced landing following a loss of engine power on approach to Paramount Air Strip (JY04), Green Creek, New Jersey. The commercial pilot sustained a minor injury. Visual meteorological conditions prevailed, and no flight plan was filed for the banner-tow flight, which departed JY04 about 0945, and was conducted under the provisions of 14 Code of Federal Regulations Part 91.According to the pilot's written statement and company records, he picked up his first banner at 0948, and subsequently dropped and picked up 5 more banners. About 1340, he dropped the 6th banner, retracted the tow boom, and entered the downwind leg of the traffic pattern for landing at JY04. At the point where the airplane entered the downwind leg, the engine stopped producing power. The pilot turned the airplane away from a line of trees in the airplane's path, and performed a forced landing to a marsh which resulted in substantial damage to the fuselage. In a telephone interview with a Federal Aviation Administration (FAA) aviation safety inspector, the pilot reported that he switched from the left fuel tank to the right fuel tank and attempted an engine restart during the forced landing, but the attempt was unsuccessful. The pilot reported that he filled the fuel tanks on the day prior to the accident, and that the airplane's average fuel consumption rate was 7.2-7.4 gallons per hour. He reported to the inspector that he "didn't understand" how the airplane ran out of fuel. The pilot held a commercial pilot certificate with ratings for airplane single engine land, multiengine land, and instrument airplane. His most recent FAA first-class medical certificate was issued October 4, 2016. His records revealed an estimated 615 total hours of flight experience of which 507 hours were in the accident airplane make and model. The one-place, high-wing airplane was manufactured in 1942 and powered by a Lycoming O-290D2, 135-horsepower engine. It was originally configured with a 12-gallon fuel capacity but was subsequently modified with a 36-gallon fuel system. The most recent annual inspection was completed on August 9, 2016 at 11,517 total aircraft hours. At 1355, the weather recorded at Cape May County Airport (WWD) 3 miles south of JY04, included clear skies, wind from 290° at 9 knots, and visibility 10 statute miles. The temperature was 26°C, and the dew point was 18°C. The altimeter setting was 30.12 inches of mercury. The airplane was examined at the scene by an FAA aviation safety inspector. Examination revealed the firewall and the tubular structure of the fuselage were substantially damaged. An FAA inspector confirmed flight control continuity, and when the fuel tanks were drained, he recovered "a little over a gallon out of the right tank, and nothing out of the left."