How to avoid bad takeoffs from a magician and a all American senior?

[Matt Curtis]

so my magician likes to roll inward on takeoff and today did so and I  burned up the electric motor on it even though the kr timer did its job if shutting things down when needed. Is that due to the longer inboard wing on this design?  I also have an all American senior that has the same design. I am going to put bigger wheels on the magician. What else can be done to prevent bad take offs? I wonder if I would have stepped back to prevent this? Flying off grass with a stooge.

[Steve Helmick]

Absolutely, be prepared to step back to keep the lines tight.

The wing offset of the Magician (how much is it?) shouldn't be too bad IF you have some wingtip weight. Remember that as the model accellerates, that tipweight is trying to stay still, so it causes outward yaw.

Do you have some out-thrust in the motor/engine? You should.

The All American Senior is another deal. IIRC, they had 4" of wing assymetry, as they were designed to fly clockwise, witwh no tipweight at all. The solution is easy if you are using 'lectric...THAT is where you should use a LH propeller, AKA "pusher".    Steve

[Matt Curtis]

Thank you for this info. I did not realize motor offset was needed on this design. Will put that in. I do have tip weight. Also will be ready to step back. Will remember to use pusher prop for all American. What about pusher prop for magician?   

[Paul Van Dort]

Long time ago there was an article in Stuntnews of Wild Bill netzeband (if I remember correctly) that stated that with more wing asymmetry,  more engine offset is required. The engine shoud have an offset so it pulls "through" the center of lift of the wing.

[Dan McEntee]

   As mentioned, engine offset, experimenting with lead out position, and making sure the airplane does roll straight or maybe pulls a tiny bit to the right. Test roll the airplane on pavement. Check the wheel alignments to each other and to the center line ofthe airplane. Like your car, it is best to have a tiny bit of wheel toe in to help a model track straight.

  Type at you later,
   Dan McEntee

[Brett Buck]

Long time ago there was an article in Stuntnews of Wild Bill netzeband (if I remember correctly) that stated that with more wing asymmetry,  more engine offset is required. The engine shoud have an offset so it pulls "through" the center of lift of the wing.

  Exactly, that is about 90% of the issue with the All-American.

   One of the WAM Old-Timers showed me a trick with All-American takeoffs - instead of holding it normally, hold it from just the tail, and raise the tail until the fuse is approximately horizontal and release it from that orientation. I think it works because you are not compounding the "yaw-nose-in" issue with precession from suddenly lifting the tail. This is not a complete solution but it makes it better.

     Brett

[EricV]

  Exactly, that is about 90% of the issue with the All-American.

   One of the WAM Old-Timers showed me a trick with All-American takeoffs - instead of holding it normally, hold it from just the tail, and raise the tail until the fuse is approximately horizontal and release it from that orientation. I think it works because you are not compounding the "yaw-nose-in" issue with precession from suddenly lifting the tail. This is not a complete solution but it makes it better.

     Brett

Eddy R built more AA Sr's than anyone I ever knew. I've built a few of my own, and also inherited one of Eddy's, and he showed me how excessive tip weight covered a multitude of sins on the AA Sr... which is comical for the plane designed not to need tip weight. Sure, it throws the wing like crazy, so don't expect a clean hourglass or modern AMA pattern because that excess tip weight will do ugly things, but for OTS, meh, it's fine and it will take off better too (aside from dragging the outboard tip on uneven ground, heh) if you are overly worried about that part. You can always remove some weight as you learn to get it off the ground. Reading the previous posts, it probably has a similar effect to excessive engine off set per Wild Bill... but with a typical Fox 2/4 setup, I might prefer the tip weight. If I had an LA25 in it, I'd probably split the difference, half the engine offset since the engine is always "on", and maybe still a touch of above normal tip weight. I dunno, I'd have to try the 2 setups back to back... offset vs tip weight... to see which I preferred since I never tried "modern" power in an AA Sr.

EricV

[Paul Raley]

With my AA Sr (RIP) I would snug up the outside wheel collar so it the outside wheel would drag a bit and the inside would spin free.  Helped some but still a handful on takeoffs. I remember mine turning and coming almost straight at me.  That is not what did it in though, a mild hard landing broke the nose off right at the leading edge.  It was a nice flyer once in the air.

[Ken Culbertson]

I would walk backwards as it went forward and in until it had take off speed then I would move forward until I was in the center of the circle.  Yes to the engine offset.  Really fun to fly once you get it in the air.

Ken

However, I think the bast way to avoid takeoff issues is to fly the Magician.

[Motorman]

Is the grass mowed down tight, are you dragging the lines in the grass? You can bend the inboard LG strut down and the outboard strut up so the inboard wing tip sits higher. Hold your handle up to head level until you get up.

MM

[Steve Helmick]

Reading the above posts about the AA Sr., I was reminded of launching an AA Sr. for Dirty Dan Rutherford. He had a Fox .35 Stunt in it with the LH crank and "pusher" propeller. He had it yawed out at least 5 degrees, if not more, and he made it clear that he wanted it that way. The reason was that if it was released aimed tangent to the circle, it would instantly yaw outward anyway. Releasing it already yawed out made for a much smoother start to the takeoff run.  Steve

[Ty Marcucci]

Dan is correct about wheel alignment,, BUT make sure both wheels are free, no drag.. If the inboard wheel is stiff and drags, it will pull the model into the circle... Guess how I learned this.