172 Tail Wheel Conversion

[lcranton]

Hi Mark, Last year I worked with a friend and we converted a 1956 C172 to a TW using the Fravel STC. As you have found out the most difficult part was making the TW attach bracket/doublers. We pulled a fiberglass mold off of the tail cone and then made a cement buck. Hammer formed 2024-0 to shape and had it heat-treated. Also had to redesign the brackets for edge distance and proper shape. If you make the parts per the drawing they will not have the proper fastener edge distance. From your pictures the ones you made look great and are very similar to ours. The aircraft was a total restoration/ modification. TW conversion, center stack panel (DELAIR STC) new radios, instruments, wiring, plumbing, engine overhauled, SkyTec starter, oil filter and new engine instruments. I did the test flights on a Sunday. It flew great! Got the owner some time in the aircraft and he left that Friday with 5 other aircraft for Oshkosh. Good trip no problems. Returned with 40 hours on the aircraft. Hope you have as much fun; It’s a lot of work but worth it.

Larry

[53B]

Hi Mark, Last year I worked with a friend and we converted a 1956 C172 to a TW using the Fravel STC. As you have found out the most difficult part was making the TW attach bracket/doublers. We pulled a fiberglass mold off of the tail cone and then made a cement buck. Hammer formed 2024-0 to shape and had it heat-treated. Also had to redesign the brackets for edge distance and proper shape. If you make the parts per the drawing they will not have the proper fastener edge distance. From your pictures the ones you made look great and are very similar to ours. The aircraft was a total restoration/ modification. TW conversion, center stack panel (DELAIR STC) new radios, instruments, wiring, plumbing, engine overhauled, SkyTec starter, oil filter and new engine instruments. I did the test flights on a Sunday. It flew great! Got the owner some time in the aircraft and he left that Friday with 5 other aircraft for Oshkosh. Good trip no problems. Returned with 40 hours on the aircraft. Hope you have as much fun; It’s a lot of work but worth it.

Larry

I saw the post about that when I was doing my research. I looked into the 2024-0 and heat treat route. I was not able to find the stock in the correct thicknesses and the heat treat was expensive so I did it the hard way. I'd love to see some pictures if you have any to share. It is a lot of work but most of the major things are done. I found that doing this to an "in service" airplane makes for some interesting issues and decisions to make as to how far to go. I hope to have it flyable in a week or two.

Thanks!

[53B]

Hi Folks,

I have my conversion done and the aircraft is ready to fly. Still waiting for the FAA to come through with my field approvals.

I wanted to let those of you doing this same conversion know that I have found an error on the tail wheel bracket blue print.
It appears that all of the fuselage station references are for a Cessna 150, not a 172.

I weighed my airplane as the conversion STC calls for and measured the tailwheel arm off of the aft bulkhead adding that dimension to the aft bulkhead station. Since the aft bulkhead station was incorrect, my tailwheel arm was off by approximately 28 inches so my CG calculations looked a bit strange.

Hope this saves someone a little time!