FIRST FLIGHTS OF MODIFIED D.D.
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From: Fairfield, CA
The first flights were very successful with speeds in the 190 mph range. Airframe is fully sheeted and foam filled to the high point on the leading edge and 2 inches of trailing edge. Leading edge is swept to 50 degrees with 1/2 inch extensions full length for a 1/8 inch radius. Wing tips and trailing edge taper down to a sharp edge with .007 by 1/4" carbon fiber inlaid around entire airframe except the leading edges which are .018 by 1/8". Vertical fins were relocated to the middle of each wing,and also reduced in size, inlaid with carbon fiber,and sanded to a sharp edge all around. Center section is sheeted with 1/16" plywood for extra strength,and didn't add much weight. Engine is Jett 60 FIRE with .075 longer con rod,sleeve raised .075 with custom spacer,exhaust timing raised to 180 degrees,bottom of piston&sleeve notched to open up the boost port,a modified OS91FX carb,and a MACS 11cc pipe with a strait header I made from a MACS Super tigre 45X. Top RPM is 20,400 with APC 8.8-9.75 cut down to 8"diameter,and fuel is Wildcat 15% with 4oz. of racing castor oil added. Fuel tank is 6oz. bladder tank,Hi-tec super slim 8 ch.rx with 2 635's on elevons,one 225 on throttle,and a 1000 MAH battery pack.The engine is going a little rich when it unloads,so there is still more speed in it when I get the carb sorted out. I did shoot some video of it,and will post as soon as I can.I will answer any questions that anyone has. Regards to all, Scott Romine.
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From: Fairfield, CA
BTW I forgot to mention that I use a 3 wheeled r/c launch cart with its own rx,batt. pack,and a steering servo which is operated with the rudder stick,and a release servo that is operated with up elevator.I will show it in the video.
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From: Tulsa, OK
What was the finished weight of the plane? How much weight did you add to the tail to balance? That is a Jett 60 case and not the 60LX, right? How did you measure speed? I will be waiting for the video but a couple of still pics would be nice until then.
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From: Fairfield, CA
Finished weight is 4lbs 1oz and did not need tail weight. I had to put the battery between the engine and the fuel tank because the increased wing sweep and foam filling made it tail heavy.The engine was originally a 60L FIRE and weights 13.5oz.(ABC version).Speed was measured by time over distance.Average of 3 passes was 1.05 seconds which calculates to 194.805 MPH.Of course this not completely accurate,but it's a good starting point.I do'nt have any still pictures,but I'll post a video as soon as I can.
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Congratulations, undoubtedly a pretty awesome combo! The distance over time deal gets pretty tough the faster you go, you're doing roughly 300 feet per second at 200 mph [quick math in head] The observers need to be stationed directly in the flight path at the set distance to eliminate perspective error, plus a pole set at 90 degrees to serve as a reference for the observer is needed too. I think to increase accuracy, the distance needs to be moved up to 1/8th mile, [660 ft] which is still a manageable distance.




