I'm flying a Bat and it flies well ........ except when it loops. It will snap at the top of the loop and not fly thru it. This looks cool but on a low pass that could be a good splat.

I have tried to reduce the throw in the elevator but it does not seem to help. The plane balances a bit nose down, maybe 3 degrees and is ok side to side.

Is this natural for this type of plane? How about mixing elev and alerion?

Thanks for any help on this issue. This plane is a hoot to fly and I am looking forward to learning to fly combat.

Thanks,

snapping out of a loop means you have too much elevator, too far back of a CG, or both.

Now, depending on your engine and prop, you can improve the performance. A harder pulling engine will pull the plane through with out dropping airspeed on the up side of the loop. What engine/prop are you useing?

I usually set my elevator based on horizontal turns, going for as tight of a sustained turn as I can get. And I don't worry if that means that I might snap out at the top after a few loops as the plane drops airspeed.

Btw, always balance the plane level. The point it balances level is the current CG. Set that CG as per the directions, or as per your preferences. I personally like to move the CG back pretty far. This puts less load on the elevator, and actually results in a tighter turn. If you're holding the plane by the spot listed in the instructions, and the plane is nose-low, then you are some random distance too nose heavy. Figure out how nose heavy you are, and try moving the CG back.

Double post deleted.

Snapping can also be helped by reflexing the ailerons up a little. Not much, just about 2 turns on the clevis. This effectively adds washout.

HTH,
D

Another thing I have found is that a little more horesepower (i.e. mousse can muffler) and thrust will help to pull the plane through the loop, without stalling the elevator and stab, which is essentially what happens in the snap. Try different muffler/prop combos, that might help.

Jay L.

Another trick to make your plane turn tighter is to dynamically balance your wing/plane, and set your rudder trim (yes, rudder trim, even though we don't have moveable rudders, we do have yaw/rudder trim by adjusting the vertical stab)

To do this, first statically balance the plane laterally, adding weight to the light wingtip as necessary.

Increase your elevator throw a bit from what you'd normally use (you want to induce some snaprolls here).

In the air, fly level, then roll up in to a fairly steep right bank, nearly 90 degrees, and haul back on the elevator. You want to turn as tight as you can while staying level, no climbing or diving, just a hard constant turn. Slowly tighten up the turn with more and more elevator until the plane snaps. It will either "snap up" or "snap down", meaning it will "snap up" by rolling out of the turn and pop upwards, or it will "snap down" by rolling inverted and heading for the ground.

Now do it again. Do several times. The plane will probibly go the same way each time.

Now, do several times, this time rolling left (or right if you went left the first time).

Most planes will go "up" when turning one direction, and "down" when going the other. If you go "up" in a left turn and down in a right turn, you need right rudder or your right wingtip needs weight.

When the plane is balanced, it will always go "up" or always go "down" regardless of which way the plane is turning.

You can also do the same test by pulling lots of loops and seeing if you always snaproll in the same direction. Properly balanced, plane will go nearly 50-50 if you enter the loop perfectly level, and straight in to the wind, with out any disturbance.

I just find the level turns easier to perform, and easier to see what happened, and know which way the plane went.

This kind of tuning of the plane can do some dramatic things to your turning radius. I've had planes where I could add as much as 20% more elevator throw after this kind of trimming. That's a LOT of turn in combat.

(of course, it's possible that "best" trimming techniques may vary with flying style. I don't loop much, I prefer to turn level rather than loop)

Thanks all for the info ......... I have reduced the elev and also reduced the expo a bit. Now I can fly thru the loop without fighting it to go thru, if I want it to snap then I can still do it and I know what it will do and where it will go.

As far as adding more ponies ...... I am going to fly in SSC class and it has restrictions on engine, muff and prop. I am using a Magnum .15, stock muff, and a 8 x 3, GF-2 blue props.

Anyone mixing elev and ailerons to help in turns? If so how much?


Thanks,
Fred420

Ah, ok, if it's an SSC plane, then that's about normal. Many SSC planes won't pull loops forever. Some will, some won't, and it's not really a huge deal if it wont, espeically on a hot, humid day when the engines aren't going to be pulling full power.