RCU Forums - View Single Post - Ail & Rud settings to slow landing by crabbing
Old 12-29-2015, 09:13 AM
  #23  
da Rock
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Join Date: Oct 2005
Location: Near Pfafftown NC
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Good luck on two things.... The weather improving, and the solution to your problem. We've been waiting out the rain for over a week now.

In following your posts, it sounds like all you and your flying friends are in agreement that your plane can only be landed one way. Sorry to hear that. And it sounds like nobody is familiar with how easy it is to trim any model's CG in flight. There are a couple of simple methods even beginners can handle. I'm surprised no one has described one. or two.

And there really aren't many models that can only be landed one way. Modelers new to pylon racing and thermal soaring often start with the belief in the long-and-low final as the only way in for those suckers. Humans have a really hard time judging speed, and our planes don't show us anything but ground speed, and it's airspeed that matters. So humans need tricks or loads of experience.

Full scale pilots are trained on the three leg approach for a reason. It has a couple of needed tricks. It breaks the landing up into segments we can shorten or lengthen to help us control airspeed. And the two turns also help control airspeed. And the two turn points also help us control altitude. Also, breaking the landing into parts helps us control the pilot workload. He doesn't have to deal with throttle, pitch, airspeed, location all together the entire approach.

Less experienced model pilots often try to get that last benefit by doing long, low approaches. They basically turn over control to the airplane.

Hope it doesn't hurt your feelings to ask if you've ever flown your AcroWot dead stick much. It's really useful to discover just how slow they go with no power, and more importantly, how fast they are going when they stall. Stall speed is mostly a function of wing loading, and you've got a design that started life much heavier and not much larger but is only 30 ounces made of foam.

On those straight in approaches, ask yourself when do you actually shut down the throttle? and what would happen if you did it farther out? That sucker comes in deadstick the whole long, low approach? Try shooting the same approach "normally" but higher up, with the goal to do a flyby at however much the model was higher up. The flyby of course will require a touch of throttle.

Another thing to try is to kink that straight in base leg (down wind, base, final) 45degrees with the turn right at the threshold. Turning any airplane creates induced drag which slows the airspeed. Then try 90degrees from base leg. Of course, do these "higher up" before trying a landing with them. Doing any of this as a flyby is safer, and the plane is close enough to see better what it's ground speed is. Working out flying problems and increasing pilot skill is the goal. And we also control how much risk we incur by choosing the altitude of the test.