I decided on an OS 50, cause that is what I had laying around. They call this a 70 size plane, but a 40 size engine will pull it at about 75-85 MPH. There is not an engine or in cowl muffler system yet invented that will fit inside w/o a lot of cutting. For sure a four stroke muffler would be best as you could simply use the exhaust header to clear the cowl. The OS and probably any other 2 stroke will require severe butchering at the exhaust and carb areas. I say carb area cause with the OS 50 up front and I mean as far front as you can get it, I still had to add a ton of weight in 2 seperate areas to get it to balance to the far aft measurement of the CG specs. (maiden was a thrill !!!!!).
Even the air scoop had to be cut on one side just to clear the muffler(a pitts style wouldnt work).
half the cheek was fremoved for the head, and a lot of front area for the carb.
It looks pretty good from the other side.
I bet an OS 90 2 stroke would just about balance this right on. I see Tower is coming out with a 70 or so size in a month or two, and it would probably be the right choice. Then engine bulkhead looks OK for that size or smaller, but if Bob gets the 60lx in it, he might want to add some wood in behind as it is void of any.
As far as the flight goes here is what I experienced:
It flies a lot like my 42% as far as the visual and perspectice out line and recognizing top and bottom contours. I am used to seeing this style of plane so it wasnt a major problem, I did hear a couple elderly flyers make the comment as it went by downwind at about 95 MPH- "is it upright or inverted, I dont know I cant tell".
Take off was fun, I discovered I was still way too far back on CG and it went vertical until I trimmed it to its maximum end point. I had the elev neutral but with too much weight to rear it climbed, and I knew it would be a fun landing when the time came.( I set my 42% racer up with the CG too far back and couldnt land it w/o ballooning it and dropping it like a rock ).
In flight was good, snapped on sharp turns with elev in put(pylon style turning), but that was to be expected with the CG way back.
It is fast even with just a OS 50 (25-30 tanks thru it). Dont let anyone say they arent fast planes this one was.
The landing had me on my toes as I tried to make a slow fly by to check out its characteristics on approach
but discovered my EPA on throttle wasnt set right and it was coming in very hot, too hot for our 600' field, so I had to get into my sub menu programs while circling overhead and set the low idle down. With that done, I came in low and slow again and it ballooned as I expected, so I went around and let it land itself and settle in on its own, which it did and touched down and stuck like glue. No kidding, one guy said- " that thing sure stays down when it touches".
All in all, with the Cg right, it would be a good pylon racer. As far as aerobatic as advertised- DONT THINK SO!!!. Definately not a trainer or first low wing plane or scale bird for sure. Compare it to a P51 for the most part.
The build was a chore in many areas, I added a pilot and instrument panel cause it is a scale plane.
Pros:
great paint (even though I wouldve liked all white) fuse was top notch f/glass kitted.
wing also excellent in structure, though not built for 130 MPH pylon turns.
hardware was standard
wheel pants look real nice and we will see how they hold up to my type of landings
Cons:
didnt care for the pull pull rudder night mare trying to feed it thru all the bulk heads
cowl too small for any engine- ruins a scale type look
Cg nearly impossible to achieve with recommended engine sizes.
All in all I give it a 7.5 out of 10 for total satisfaction, although it is a real eye catcher since most fliers have never seen anything like it.
A 10 out of 10 in cosmetic appeal (except for cowl area)
A little pricey for what you can do with it once it is done, but I just had to have it.
Pics will follow shortly
Race101