Mid Engine Design-Air Corba & Stilleto

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A few of you have asked for more details on the Mid Engine design that I used on the P-39 Air Corba, so here goes.
Since I retired a few years ago I wanted to find somethig to do besides fishing. I wanted to get into Cox model planes like I flew back in the 1950's as a kid. Back in Nov. I was looking at plans on E Bay & found the "Stilleto" and just had to build it. I had just started when the Speed Contest started so I switched over to The P-39 and built a profile design to enter. The P-39 was used in WWII in the Pacific but also used by other countries , mostly Russia. The P-39 & the later version the "King Corba" were both used in the Reno Air Races and the "Thompson Trophy Race in 1946 was won by Alvin "Tex" in a Air Cobra. The Thompson Race was a 30 mile course for 10 laps a total of 300 miles.
I also found a lot of info on the Reno Air Races at : AAFO Hangartalk--P-39 Racer. U tube has a lot more of course , just type in P-39 Air Cobra & Reno Air Races.

The Stilleto can be found on E Bay under Model Airplan plans in RC & Control line at: the Vergina 123 Store under "Model airplane vintage proto speed plane y2a. The plans come on a disk and are very complete, with a lot of engine details.

The pictures above show the drive train I used in the Corba with a 1/4" I D brass tube holding 2 slip bearings and a #5 steel rod threaded with a 5-40 die. This is not the design used in the Stellito which is the larger #8 steel shaft with the u joint & in the alu. tube. As soon as time permits I will go back to the Stilleto so more on it later.

The picture shows the the drive shaft & engine in the test stand that I used, unfortunately I dont have a way to measure the RPM's to find out how much I am losing. The compents are shown with the upper flange bering out of the tube. Its a pretty simple method once you get the parts.

Hope this helps, RK Flyer