John Rist built a 1/2a scale model of the Dornier Do-335
The full size aircraft had a engine behind the pilot with a shaft that drove a propeller in the back of the aircraft and had an engine in the front.
John duplicated this with a pair of .049 engines for the 1/2a scale event.
John has built two of these before and has incorporated some changes based upon the first two models. Sometimes you have a build a model and then figure out what does and does not work and then build the final version that really works good.
The shaft was designed by John and machined by Jim Lee out of Topeka Kansas