This is a working replica of Irv Ohlsson’s original .23 powered “Pacemaker” free flight model airplane. This is one of four replica Pacemakers to be built. The model was built by Fallbrook, CA local Dan Lutz to duplicate Irv Ohlsson’s championship winning Pacemaker (which can be seen along with Irv in the photo below). Mr. Lutz’ model Pacemaker is powered by an Ohlsson .23 engine just like the original.
The aluminum cowling was actually made by Mr. Ohlsson himself out of a used aluminum printing plate. It had to be annealed in molten lead multiple times as it was pounded to shape over a wooden buck. When metals are stretched or compresses with hammers they become harder and less malleable. This is called “work hardening.” The metal must be heated to just the right temperature and then properly cooled to return them to the dead soft state–then they can be worked further.
Mr. Lutz also built a replica Ohlsson Pacemaker floatplane, which is almost identical to this model except it was built to takeoff and land on the water, and is radio controlled. The Pacemaker floatplane, along with a scale model R/C F4B-2 biplane and an R/C Piper Cub, were donated to the Miniature Engineering Craftsmanship Museum by Dan’s son, Dennis Lutz. This original Ohlsson Pacemaker was donated to the museum by Gus Ohlsson.
