RCU Forums - AVISTAR TIPS

There are a few things I've recently learned as I helped my grandson get started in RC on an Avistar that might be helpful to new-comers to this hobby.

First, this is a very good choice for a beginner. While not possessing the inherent recovery characterisitics of a flat bottom high mounted wing, it is quite stable, and as you progress it will be capable of a lot more advanced flying because of the semi-symetical wing. As general information that you are probably tired of hearing, a high wing causes a plane to pitch up as it gathers speed because of all the drag up there, and a flat bottom wing creates much additional lift as speed is increased. These two things help the plane recover from dives quickly, a safety factor when learning. As well, a plane with a lot of dihedral (is that how it's spelled?) cause the plane to level its wings automatically because the lower wing panel creates more lift that the upper wing panel because the dihedral makes it look parallel to the ground while the upper panel shows much less wing area. Roll your plane about 20 dgrees and look at the area each wing panel will have lefting. As you progress, however, you learn to appreciate a plane those continues going where you point it, and that favors a shoulder wing with a symetircal airfoil and little dihedral.

This is not a slow plane with an OS 46 FX in it. In fact, it may move a bit too fast. Many will argue that you can throttle it back and have reserve power, and that is true. Just remember that when you're up there trying to keep track of it. Fly it on 1/2 throttle once at altitude. I would think an OS 40 LA would fly it very nicely, but again, the FX will give you reserve power for later. Remember, though, it's a very fast trainer with an OS-46-FX in it, very fast.

You can expect the fuel tank to fail and begin leaking. The only question is when. But there is a way to avoid much of that. The tanks I have seen that have failed have split at the neck and started leaking around the rubber stopper. The way to avoid this is to get some strong thread, the kind you can't break with your fingers, whatever that is, and wrap the neck with about two very tight layers all along its length before you install the tank. Then hit the thread with some fast glue and let it set. That's what we did with the second tank and there have been no problems.

On the landing gear, the way to control the springiness that causes the plane to jump back off the runway if not nailed just right is as follows - We installed 1/2" long screws on the inside axle collars, the ones that go between the wheel and the landing gear arms (versus the collars that go on the outside of each wheel axle to hold the wheel on). These will stick up at least 3/8" out of the collars. Then get some fine wire and lash the two screws together across the landing gear, thereby tying the two landing gear arms together near the wheels. This will keep them from springing. If you fly in grass, get oversized collars and slide them up the landing gear a ways, perhaps two inches, tighten the 1/2" screws, then lash the screws together.

As to flying, get this. My grandson spent some time on the Great Planes simulator down at the local hobby shop when he was determining if he wanted to learn this hobby. The first time I took him flying I got altitude and had him take over at 1/2 throttle. He seemed very stable, so I had him cut throtthle to about 1/8 and make a pass over the runway about 20 feet up. Him and that plane were so stable, I had him cut the throttle to idle and then talked with him to have him focus just on keeping the plane level in roll and pitch using very small stick movements (the key to good landings), and he slid it right in. He still hasn't crashed this plane and is on his third gallon of fuel.

Lastly, this plane isn't very happy at speed in a wind. Coming out of loops it may zoom wildly and may even roll hard if not pointed directly into the wind. I'm talking 10 MPH and up winds and speeds obtained with an OS 46 FX using a 10-6 prop. Once you're airborn, throttle back in a wind, and learn to use throttle through a loop to reduce speed as you go over the top and start down. The zooming can be so violent, I wouldn't be surprised to hear of a wing snapping.

Take care, Fred