Don Srull has built hundreds of airplane models, including the PWS-10, a 1930s-era fighter flown by the Polish air force. Donald W. Srull, a longtime designer of model-airplane plans published in ...

138 g airplane at 10.2 m/s is 7.2 J imparted to the load. His current numbers don’t add up (claims 90 amps at 48 volts, but measures 2 ohms in the maybe different coil).

The inaugural “Vintage Models Over Valley Forge” event on Sept. 30 attracted vintage model airplane enthusiasts from several states, local hobbyists and spectators. Held at the Valley Forge ...