On March 17, 2019, about 1745 eastern daylight time, a Cessna 421B airplane, N424TW impacted terrain near Plain City, Ohio. The commercial rated pilot, sole occupant, was fatally injured and the airplane was destroyed. The airplane was registered to Classic Solutions, Inc. and operated by Phoenix Test Flight, LLC, as a 14 Code of Federal Regulations Part 91 flight. The flight departed Dayton (KDAY), Dayton, Ohio about 1720, en route to (KDLZ) Delaware, Ohio. A preliminary review of radio communications revealed the pilot was in contact with air traffic control and there was no record of a distress call. The pilot requested runway 28 RNAV approach at KDLZ. The pilot also reported that he was encountering icing. The controller cleared the flight to 2,500 ft. Shortly afterwards, the airplane made a left turn, and radar and radio communication were lost. The airplane impacted a rural field about 8 miles southwest of the KDLZ airport. Ground impact scars and wreckage were consistent with a left-wing low impact. The wreckage path was orientated on about a 140-degree heading. From the initial impact point, the airplane crossed a two-lane road before impacting two wooden utility poles. The main part of the wreckage came to rest at the base of the second utility pole, about 395 ft from the initial impact point. The wreckage path was about 850 ft long with the wreckage highly fragmented along the wreckage path. There was not a post-crash fire. After documentation of the accident site, the airplane was recovered for further examination.