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Old 06-22-2003 | 07:27 AM
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aeajr
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From: Long Island, NY
Default firebird xl cg

I fly an Aerobird, but it is a very similar plane to the Firebird XL so some of the tips and fixes I give here may apply to your problem. I have been flying my bird for three months and 50+ flights and just lovethe
plane. I have pounded the plane into the ground, destroyed three wings, and a
tail. I had to build a new motor mount because I destroyed that too. All
this, and the plane flies great, but it has taken a real beating. That is
what makes it such a great three channel trainer.

Along the way I have had to solve many problems brecause I was so reckless
with it while I was learning to fly it. So, I pass on what I have learned.


First - RTFM

If you lost your manual, you can download it here:

http://www.hobbyzonesports.com/Produ...uctID=HBZ6000#


Respect Wind

This plane can fly in winds up to about 12 MPH and I have flown in 15 MPH
winds. However wait till you have mastered it. Most of my crashes came from
flying in too much wind before I was ready.

Always launch into the wind and land into the wind. And, with the wind
blowing toward you, the wind
will not carry your plane away, it will tend to bring it to you. Once you
master flying the plane, the wind can be your friend. Respect the wind, don't
fear it.


Motor Mount

This is the first thing you should do. Before you take a hard nose hit,
reinforce the motor mount. I will not elaborate here, visit this thread to
find the information. It contains advice from other pilots and what I finally
did to reinforce the mount. You should do this before you need it.

http://www.rcgroups.com/forums/showt...187#post922187


Plane Does Not Fly Straight

Assuming you have not displaced the motor (see above), and you are having
problems with the plane turning to one side, check the following:

a) is the wing crooked or too damaged - try a new wing.

b) Check the trim adjustments. They may have been moved from center. Set
them to center and make all adjustments assuming you will fly with the trim
set in the center.

c) Check the tail. The foam is attached to the center plastic brace by small
pieces that punch through the foam. This can loosen up and the tail fin can
move slightly away from the plastic brace. On the ground you might not notice
it, but in the air the pressure can move this around causing the plane to turn
to one side or the other. Tape or glue the tail fins to the center
plastic brace. Also, look for creases in the foam. If there is a weak spot,
it will cause the tail to flex causing the plane to turn. mine was creased at
the meeting point where the plastic support meets the tail, so did not see
it. Looked fine on the
ground, but it was flexing in the air causing a hard right turn leading to
crashes. I replaced the tail.

d) Make sure the moveable surfaces are even with the fixed surfaces on the
tail when the stick is centered and the trim levers are centered. You MUST
check this with the transmitter on and the battery attached. If they are not
even, adjust them with the screws on the control horns. If they are not even
when the stick is centered, then the plane will not fly right, ever. The
procedure is in the manual. RTFM

Note, there is a tiny phillips head screw on the back of the control horn on
the tail. Tighten it or the spool could unwind while the plane is in the
air, causing a crash. (Guess how I know this!)

e) If none of the above are not a problem, then check to see that the boom is
solidly attached at the body of the plane. If this comes loose, it can move
around while the plane is flying causing all kinds of problems. It can also
twist so that the tail is no longer aligned. Since the body is polypropylene,
not much in the way of glue sticks to it. This links shows you how one person
secured the boom on their plane using screws.

http://rclibrary.com/viewtopic.php?p=34#34

Be sure to put the screws FORWARD of where the control lines enter the boom.
You have to look into the plane to see this point. I have also heard of
people drilling holes from the side and putting nylon ties through the holes
to secure the boom. Just make sure you are forward of control lines.


The Porpoise

When you apply power the plane starts to climb then noses up, then the nose
drops and it does it all over again. The problem is that the tail needs to be
trimmed. There are two screws on the tail. The procedure is in your
instruction book. RTFM


Center of Gravity

If you are using a 7 cell battery, you will get a faster plane and better
climb. However you will also shift the center of gravity forward slightly.
Not enough that the plane won't fly, but enough that it will seem to be nose
heavy. If you are an aggressive, full throttle flyer, you probably won't
notice. If you are more of a half throttle cruiser, like me, you will find
the plane needs up trim all the time. Here is how you fix it.

The foam that sits between the battery and ahead of the electronics puts the 6
cell exactly where it needs to be to balance the plane, but the 7 cell is
heavier. Remove the side pins and pull the foam out. Now, cut it from top to
bottom about half way in, just in front of where the pins that hold it
in-place enter the foam from the side. Now put the remaining piece back in
the plane. When you fly the 6 cell, put the moveable piece behind the battery
in its normal place. If you are flying the 7 cell, put the moveable piece
forward of the battery. This will shift it back 1/2 inch and put the CG right
where it should be. The plane will fly better at all speeds and will launch
much better as well.


Longer flights

Bback off on the power. Both the 6 and 7 cell battery will last five to
seven minutes at full power. However, if you back off to half power, your
flights can last 10-12 minutes depending on the wind. If you back off to 1/4
throttle or glide, you can stretch beyond 15 minutes.

Also, when you charge your batteries, charging at a lower rate gets fuller
charges. If you are not at the field, but are charging up after the day is
over, or the night before, charge at .6 to .8 amps instead of the full 1.2
amps. It will take longer, but will heat the cells less and will more fully
charge the battery.


Neck Strap for the Control unit.

If you look at the high priced Futaba, Hitec and other radios, they have a
place where you can clip a cord so that the radio can hang from it leaving you
two hands to make adjustments on the plane. I have messed up the trim taps
more than once and crashed on launch because I tucked the radio under my arm.

Take a large paper clip and bend up the center piece in the middle to make a
place where you can clip a neck strap to it. Now take some sand paper and
sand a spot in the center of the radio to the left of the stick and the right
of the throttle slide. Mine is about 1/3 from the bottom of the radio. Sand
the area, then epoxy the paperclip to the radio. Use plenty so you can really
embed the clip in the epoxy. Now, when you are getting ready to fly, you can
release the radio without putting it down.


Reinforce the Wing

Got to staples and get some glass reinforced tape. The 3M type that has a
cross pattern is best. I think it is called extreme strength tape. Put a
piece on either side of trailing edge where the prop wants to bite the wing if
a landing is a little rough. Make sure you have a spare prop. Since the prop
is less likely to cut the wing, if it hits the wing, it might pop the prop
off, or break it. However normally this does not happen.

I also reinforce the front of the wing with the same tape where the rubber
bands come across the wing. This will help reduce denting.


Learn to Dead Stick Land

If you run the battery too long, the speed control will cut the power to the
motor while preserving power for the control surfaces. If you learn to land
with the power off all the time, then if you get caught in the air with no
motor, you will have no problem landing. Dead stick is my standard way of
landing. If I am 250 feet up and want to land, I just set the plane into a
landing direction then cut the power and glide it down. Also, since I fly on
a grass field, I never use the landing gear. I just slide it into the grass.


Parts

These planes have a great distribution system. Parts are very readily found
in most hobby stores. However if you can't get what you need, look here:
http://www.hobbyzonesports.com/Support/


HobbyZoneSports Frequently Asked Questions - Couldn't hurt to look!

http://www.hobbyzonesports.com/Support/FAQ.aspx


Summary

So, that is the sum total of what I know about getting a great plane through
the phase where we pound it into the ground trying to learn to fly. Don't
give up! Avoid the wind, take your time and you will get it! Oh, and RTFM
..... read the friendly manual!!!! :-)