new scratch built flight streak ?'s

Having built many Flite Streaks, I will say they make a very competitive flyer. So in order to figure out some of your problems, I would need some more info. You didn't list your engine, prop, diameter of lines etc. I can only assume this is 1/2A due to the 44' lines. When you say your CG is 1" past, which way fore or aft? How much elevator throw approximately and what size bellcrank? Your handle spacing is also relative here .

Seeing your confident in wingovers and the plane was capable, how was the overall speed of the model? How large is the control horn on the elevator and is it adjustable? If so, give the elevator some quicker throw by moving the pushrod closer to the pivot point. If your using Cox engines, the 44' lines is a bit much. The line length from handle to center of plane should be a min of 35' and I personally would only use longer if the engine was a strong runner keeping the length no greater than 40'.

When I find the CG to be questionable, I use two methods to find the sweet spot. I have rolls of golfers lead tape. I can cut a strip off where I can pinch it onto the fuse. When I get home I weigh how much it is and replace it burying it into the fuse. I also use piece of modelling clay which I can squish onto the fuse.

oldguy wrote:Hello guy's I don't post much but I do read the forum.  I'm not a consistent participant in flying control line off and on but I do enjoy messing around with it. I haven't been doing much with flying. But lately have the urge to do some more playing around. Well on to my question, feel free to comment on anything.  I finished up on a scratch built flight streak and took her out to fly this last week.  it flies stable but is very sluggish to turn, in the video you can see all I was doing was wingovers, I could tell just by the feel I didn't even want to try any loops.  And it was on 44'lines when I flew it.  Questions are by looking at the video is it just tail heavy?  The cg is 1" past leading edge.

Sorry meant to add video and picture. How do you post pictures and a video to the posts?

 It's a Jr size F/S  fox .15.

https://youtu.be/QC5rkbeZrSI

The speed looks correct, but seeing how your flying on 44' lines, I find that to be a bit questionable as you should be 50'-52' range. What I also find questionable is the phrase you used when you said it flies stable. A Flite Streak is usually a very flighty plane and not one for the beginner. It generally needs to be tamed the opposing direction your seeking which is from flighty to stable.  In addition, a plane of that size can fly on .012's vs .015's. What prop is on your .15? Seeing your using a wood prop is a good thing as the Fox prefers wood over heavier modern stuff but they're getting harder to source.  One thing I discovered with the Fox's is that they don't really care for 8" props. A 7x6 makes them much happier and also allows the plane to turn easier. You made no mention of line tension. I assume this is ok  which takes the warp factor out and that your main concern is the turning aspect. Is the gear a single gear or did you make a conventional 2 wheel landing gear?  The added weight of another wheel and drag could certainly explain some nose heaviness.

       By the looks in the video, you were practically doing large loops. So in the event your confident that the plane is just sluggish, it appears  to  me as if the controls are too slow. I would try and speed them up with the control horn and re fly. If that assists in the turning ratio but doesn't resolve it, I would then begin adding tail weight.

         The Streaks have very short noses in front of the leading edge, did you extend the moments to accommodate the tank or engine?  Even your spinner is a contributing factor. I would use your fingertips and balance the plane with one tip on the forward leadout guide exit and the other in the same place on the outboard wing. If the plane is nosing down it suggests to me your too nose heavy.

Ken Cook wrote:The speed looks correct, but seeing how your flying on 44' lines, I find that to be a bit questionable as you should be 50'-52' range. What I also find questionable is the phrase you used when you said it flies stable. A Flite Streak is usually a very flighty plane and not one for the beginner. It generally needs to be tamed the opposing direction your seeking which is from flighty to stable.  In addition, a plane of that size can fly on .012's vs .015's. What prop is on your .15? Seeing your using a wood prop is a good thing as the Fox prefers wood over heavier modern stuff but they're getting harder to source.   One thing I discovered with the Fox's is that they don't really care for 8" props. A 7x6 makes them much happier and also allows the plane to turn easier. You made no mention of line tension. I assume this is ok  which takes the warp factor out and that your main concern is the turning aspect. Is the gear a single gear or did you make a conventional 2 wheel landing gear?  The added weight of another wheel and drag could certainly explain some nose heaviness.

       By the looks in the video, you were practically doing large loops. So in the event your confident that the plane is just sluggish, it appears  to  me as if the controls are too slow. I would try and speed them up with the control horn and re fly. If that assists in the turning ratio but doesn't resolve it, I would then begin adding tail weight.

         The Streaks have very short noses in front of the leading edge, did you extend the moments to accommodate the tank or engine?  Even your spinner is a contributing factor.  I would use your fingertips and balance the plane with one tip on the forward leadout guide exit and the other in the same place on the outboard wing. If the plane is nosing down it suggests to me your too nose heavy.

Thanks Ken for your comments.  I used the 44' lines because my 52' line set had a bad kink in one of the lines so I used a set of 44' .012 set to fly it to see how it fly.  The wooden prop is a 8x4, I have found that the fox .15"s I have had performed better with a M/A 8x4 prop than the wooden props. I wanted to try and use a 7x5 but don't have one on hand at the moment.  Line tension was fine I wasn't doing any loops, but it does look like it in the video. This scratch built FS is of my own design, it is some what different than the standard kit. It does have the two wheel setup. And the nose is built up differntly .  I plan on removing the spinner next time out and will have some different size props to try out also. I also have moved the control rod down to the lowest hole in the control horn.  I quess what I was trying to get at, is what was a list of things that would cause the plane to be so slow to turn.  Like nose heavy,  Elevator size.
elevator deflection amount.  Another question I have is at the end of the video, the planes outside wing seems to be low. Does it loo to have to much weight on the outside wing tip to you?  The plane weighs 15.9  with a 2 oz tank. Here's a picture of the plane showing the nose better. Oh one more comment, the plane as it is now will not balance at the leadout, not even close.



Thanks Jim

Jim, I have to say seeing your Jr up close it's very nicely done. Very Very nice. I learned early on that elevator size is not important in terms of size because the Streak proved that for me. Using the Ringmaster as a example, the Ringmaster has too much elevator vs the Streak. The large elevator of the Ring causes it too stall. This is why limiting elevator travel on the Ring is so important. I strongly feel your just in need of some tail weight and all will be good. In order to figure out the tip low condition I would carefully look at the wings. If the inboard wing is twisted down a bit, it will cause the plane to roll outboard tip down, if the outboard wing is slightly twisted upwards, it will also cause the outboard tip to drop. I would take the plane inverted and see if the tip goes high and this would indicate a slight warp.

Thanks Ken, iw ill on the next time out with the FS I will start by adding a 1/4 oz of tail weight. And when I get it inverted I will watch the outboard wing position.
Thanks again.
jim