Hmm, let's see. I will say that this plane was sort of built on the fly and now I'm having to back track to actually have plans for it. I sketched up what I wanted. Just enough to be able to build it, cut the plans into templates then did a lot of improvisation along the way as I decided that this or that wouldn't work as I envisioned and had to change things. It never really occurred to me that anybody else would want to build one. I didn’t think I’d ever want to build another one.
I was talked into building a profile by Pat Johnston and the infamous Mark Scarborough. While I like profiles, I really hadn’t intended to fly in profile class. But hey, I figured, why not? But as is typical of me, what started off as a "just whip something out" turned into a kind of test project and I got a bit carried away as things progressed.
I wanted a plane that was a bit smaller than the normal stunt plane but significantly overpowered. I wanted to use an OS40VF since I had a couple of them in the drawer, but that presented quite a few problems. Not the least of which was, it's a pig. So it was really designed around using this engine. The nose uses standard formers (F-1, F-1 routine) with full length maple mounts. Once the engine crutch was built, it was put into a frame of 3/4" balsa and a tank compartment built from 1/8" lite ply was installed. Once that was all glued together, most of the 3/4" balsa was hogged out and nose blocks were carved up and hogged out. The fuse is done in two pieces. The nose piece as described and the rear part that is framed up from a core of 3/8" balsa with a skin of pretty hard "C" grain 1/8" sheet. A bit of carbon tow was used to improve torsional stability.
The original gear was wire, but it clearly wasn't going to work so I whipped up a quick plug and mold and laid up the carbon gear you see. That seems to work pretty well (again, a bit carried away, I guess).
The finish is dope and silkspan on the fuselage and Coverite Red Baron transparent yellow on the flying surfaces. At least I think that's what it is. It is for sure on the wing, but the stuff on the flaps and tailplane was some stuff that I've had hanging around for many years that it turned out closely matched the yellow paint I used. I thought the stuff I had was the same as the Coverite and I think it is, but over the years, it seems, Coverite changed the color so the wing is a bit darker than the rest of the covering. Oh well.
Statistics:
The wing is about 56 inches long, 616 square inches. About 5.8” asymmetry. 9 3/4" nose moment and a very long tail moment to balance that piggy engine. Tail plane is 28% of the wing area with very slow controls. I really lucked out with the tank location. I've built a profile in a long time and didn't allow for vertical adjustment. Sigh... It runs just the same upright as inverted. A bit of luck there. Final weight is about 50oz. 3oz heavier than it could have been, a lot heavier than if I'd used a lighter engine. I started off on 62’ lines for quickly jumped to 67 footers. Works pretty well with those.
This plane is the most fun to fly of just about anything I've every had. It's just a blast. The power is controllable and even in the wind, it just thuds along. Hope to have plans for it soon. I feel a full fuse version coming on.
Garf,
The tank is just a box. The rear cap is tilted in to allow a bit more head pressure, but really, it's just a box. Sure has a nice, dead steady run.
Gary,
No, this was my own design. I wanted what was a modern design that captures the feeling and look of a Ringmaster. I feel like this did that.
It's been suggested that the plans show just the normal profile, sidewinder engine installation. I suppose it could be built using an OS46LA or similar. But I'm not at all sure how it would fly like that. Fine, I imagine. But this plane really was designed around using the 40VF on a pipe, so a lot of things in the design are specifically done for this power train. Using a lighter piped engine wouldn't be a bad thing. The tail moment could be shortened an inch or so and it would probably be great. I am thinking about doing another like that and using a PA40UL (a good 3oz lighter than the 40VF).
Randy,
Hey, it's simple.
I probably wouldn't have done this if there weren't a bunch of guys at the Northwest Regionals last year using Imitations with pipe engines. So I figured, why not?
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