On March 13, 2019, at 1617 eastern daylight time, a Beech E55, N15VK, sustained substantial damage during a gear-up landing at the Albert Whitted Airport (SPG), St. Petersburg, Florida. The commercial pilot and the passenger were not injured. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight that departed Lakeland Linder International Airport (LAL) Lakeland, Florida, at 1515. The pilot stated that became distracted and did not extend the landing gear before landing. The airplane slid on the runway resulting in substantial damage to the left wing's rear spar. The propellers and flaps were also damaged. According the airplane's Pilot Operating Handbook (POH), page 6-10, "If either or both throttles are retarded below an engine setting sufficient to sustain flight with the landing gear retracted, a warning horn will sound intermittently." The airplane was equipped with a gear warning horn; however, both the pilot and the passenger said the horn did not sound. The horn was functionally checked during the last annual inspection with no deficiencies noted. The horn was also tested after the accident and it worked as designed. The pilot held a commercial pilot certificate with ratings for airplane single-engine land and sea, multi-engine land, and instrument airplane. He also held a certified flight instructor certificate with a rating for airplane single-engine land. The pilot's last Federal Aviation Administration (FAA) third-class medical certificate was issued on February 11, 2019. He reported a total of 3,706 hours, of which, 1,217 hours were in multi-engine aircraft. Weather reported at SPG at 1653 included wind from 090° at 11 knots, visibility 10 miles, and clear skies.