jatoo

I've been having some trouble with my Aerobird.
I took it down for a flight when there was NO wind at all. Started with the routine no power toss to check the trims. Turned to the left. Trimmed it full to the right with the radio trim. Still turned to the left. Trimmed it on the plane. I had to take the left control up about 2mm higher than the tail surface just to keep it level! (Don’t ask me what that is in imperial, probably about the width of a floppy disk). Now that it was flying level I tried out a powered flight. It turned very sharply to the RIGHT. No matter how far I moved the control to the left it still turned right. It was a lucky wingtip first landing rather than hitting the nearby footy poles.
There was no wind.
There are a few dings in the wing (no effect before)
There are a couple of holes in the back of the wing (no effect before)
The body where the battery goes is slightly bulged allowing the battery to slide a bit, but I didn’t think that could affect the CG much, but requiring lots of correction at low speed and little at high might suggest CG. Is there much that can go wrong with CG in an Aerobird?
All help is appreciated.

MeltedPixel

You should never just throw your plane without power!
It will not have enough power to glide down, thus creating a stall. Thats why your Aerobird was tipping to the left, because you where stalling. When you added a ton of rudder to keep the plane leven when tossing it, that only counter acted the stall, but it must have fallen fairly fast. Once you power up and have air flowing over your tail, it will make your plane want to turn really sharply right because you where just chucking the plane.

A stall is when there is not enough airflow to keep the plane in the air, making the plane litteraly stop flying.
The aerobird is not a glider, and even gliders cant get going by just chuking them straight. With power its another storry, because the prop is PULLING your plane through the air.

Matt Kirsch

My Feedback: (21)

I kinda agree with the melted one. You created the second problem by "fixing" the first.

IF your wing is badly damaged, it may do you a world of good to replace it with a new one. I know it's probably inconvenient and relatively expensive, but you need to fix what's broken before you can figure out why it's not flying right.

Make sure the tail is snapped into place. It may have come loose in a crash. There are many threads on the aerobird on this site, and at rcgroups.com, with modifications and upgrades for the Aerobird. Run a search and see what's out there.

If the battery's flopping around inside the plane, find a way to secure it in the front of the bay. CG problems don't generally affect left and right turns, they affect up and down. A chunk of foam rubber, or a piece of velcro should do the trick.

Go over the plane inside and out and carefully look for any damage. Whatever you find, someone else has already fixed and wrote about it online.

Above all, don't keep throwing the plane over and over and over if it's not flying right. If it didn't fly right the last time, it's not going to magically start flying right the next time. You need to make adjustments. Some people will just keep throwing the plane until it's in pieces

shams42

My Feedback: (1)

I agree. I have been unable to toss the plane fast enough to keep one wing from stalling. You might try returning all adjustments to center on the plane and the radio and then gove her a good toss on a windless day at full throttle. My aerobird always tries to drop the left wing until it gets moving... then the plane levels out nicely and no horizontal adjustments are required.

Matt

jatoo

Thanks for all the advice.
I was told that throwing without power was a good way to check the trims and I have ALWAYS done it before a flight. As long as it is a good firm throw it NEVER stalls. I have only stalled a no power throw if i have thrown it very gently or upwards. I can usually get it to glide 30 feet with no power easily. I have clamped the body of the plane around where the batteries are and it is now back to normal and no longer bulges out. When all my exams are over I will take it out again and have a go. If you have any more advice please give it to me.

aeajr

My Feedback: (2)

I have an Aerobird with over 100 flights. I have taught several people to fly their Aerobitrds and would never advise an unpowered toss. Aside from the wing stall, with the motor off, you are not getting the effect of the torque of the motor, so when you turn the motor on, the plane will handle differently.

I also fly gliders. These we do throw unpowered. But they are made to fly this way. The Aerobird will glide, but it is not designed as a glider and will generally stall on a hand toss.

Here is the procedure I tell people to follow to get the plane to fly straight. I can't be sure how much damage you have done to the plane with the power off tosses, so let me just offer this as a starter.

Unless you have removed the white foam that sits between the battery and the electronics, ignore CG for the moment. Do all of your flight testing with the 6 cell battery. The 7 Cell makes it nose heavy and will change the way it flies. When we are trying to fix it, I would use the 6 cell only.

1) With your transmitter on and all trims centered, and your battery connected in the plane, but
with the motor off, look at the control surfaces on the tail from the back.
Are the movable parts exactly even with the fixed parts? If not then you are
going into a turn the moment you launch assuming the motor is straight and the
tail is straight. More on that later. Normally, these surfaces have to be
perfectly aligned.

2) The boom between the pod an the tail - is it solidly anchored or can you
move it around inside the plane. If it moves, it has broken lose. This must be
fixed. It will either sag causing the nose to go down or it is twisted causing
the plane to turn right or left.

3) Check the tail, especially by the rigid plastic near the boom. Are there
any creases? I had a problem with my Aerobird that caused it to turn to the
right so badly that it crashed because it would go into a spiral. I tried
everything. Turned out there was a crease in the tail that caused the tail to
flex under pressure. On launch, this could take you into the ground.

4) It is possible for the tail to shift from a severe nose crash. There are
trim
instructions in the owner's manual. AFTER you have checked the other items and
fixed or found them to be OK, try trimming the tail for more up or down force.


Other points to be aware of:

When the motor is running, more air moves across the tail so that you get a
faster response for turns. The slower the motor is running, the slower the
plane will respond. When gliding, response can be very soft.

Make sure you are launching into the wind - directly into the wind, or the
plane will be turned by the wind when you launch. Same for landing.

Let me know how it goes.

If this doesn't help, I invite you to post photos. These are what I would want to see:

view from nose to tail - level with the top of the plane - to check allignmets

view from tail to nose - same reason

Remove the wing, lat the plane on a table with the tail hanging off the end. Place a ruler under the body extending to the tail. I want to see if the boom is straight


surface allignment
view from the tail at tail height - full left command
view from the tail at thail height - full right
same - full up
same - full down

jatoo

aeajr,
Thank you very much for all the advice, it's always good to speak to someone whos got experience with this. Once again I have ALWAYS done a no power toss and never experienced a stall, it glides nicely to land about 10 or more metres away. Try it with yours, as long as it is a level throw with a firm toss it will go nicely.
I finally had the chance to take it out again thismorning. I checked the control surfaces and they were level with the tail, so I gave it a no power toss and it glided nice and straight to land. With minor trim adjustments I took it up into the air, the trim from now power worked well for flight, it kept level although I think it turned one way slightly more easily than the other (prob torque). That didn't bother me as long as it went straigh without me touching it. I've had the body (where the batteries go) clamped for a few days, as it had been bulge out, and I think the batteries sliding around could have been what was causeing the prob. It seems to be fine now, but who knows? Not me.
The control lines are on the second closest hole to the control surface at the moment, but it is very soft, I find myself moving the stick all the way to one side, just for a normal turn. I think i'll try moving them to the closest one. I've aso started to try some aerobatics. Well just one move actually, stall turn, I'm getting better at it but I'm not game to try a loop as I'm worried about my wing folding, it has a chunk out of the back, and a couple of bumps. Is it likely to fold?
Picture attatched.
Once again thank you for being so helpful

aeajr

My Feedback: (2)

I don't think you are likely to fold the wing. What kind of tape did you use to fix it.

I usually use fiber reinforced tape to protect the wing before the prop bites it. The one I like best is a 3 M product that has crossing fiber glass in it.

I don't think you said, is this the original Aerobird or the Aerobird Challenger?

jatoo

Yeah, the tape i used came with my JP Zagi SI (which I still can't fly) foam slope soarer. It's just like normal packaging tape I think, would gaffa tape be good? (Incase you don't know its like a fabric sorta stuff, tpe with thread in it.
I have the original Aerobird.
Should I run a strip of tape along the underside of the wing to reinforce it?

aeajr

My Feedback: (2)

I know gaffa tape from my theater work.

Use packing, or your ZAGI tape to repair, but to protect, I would recommend fibreglass reinforced tape which will fix the cuts and help resist future cuts.

I usually take a new wing and apply about 2-3 inches of 2 inch tape on either side of the rear where the prop would hit. I start it on the top and roll it around the trailing edge to the bottom. Helps prevent cuts before they happen.

I also put on strip, about 2" in the front center where the rubber bands go to help reinforce ths area. I believe the new wings already have some reinforcement in these areas.

jatoo

That's how I know gaffa!
Where can I get the fibre glass tape? Hobby sho? Kmart?
When I get a new wing I will definatley dp that.
Should I put a strip running on the underside for reinforcement in loops?
Once again, thanks for all your help.

aeajr

My Feedback: (2)

How is your Aerobird flying?

jatoo

My Aerobird seems to be flying fine. (however it is my only plane (except slope soarer which I can't fly!)).
Although I'm constantly finding myself giving it full stick movement, and I'm planning to make it more responsive, at the moment they're second hole closet to the surface. But everytime I fly it goes up, I have fun, it comes down, so simple logic doesn't tell me to change it! But hopfeully I'll get around to it sometime.
One problem (which is really getting on my nerves[:@]) is that sometimes when I cut the throttle, it doesn't cut! It goes down to a bare minum. Although this doesn't affect it's flying much, it makes landing a bit tricky, it really won't get on the ground, which almost resulted in a very nasty crash. Has theis happened to you? Or any other Aerobird owners?

aeajr

My Feedback: (2)

If the throttle won't go completely off, contact the hobby shop, on-line store, or horizon hobby, the distributor. You may have a defective speed control, or the speed control slide on the radio.

Is this an orignal Aerobird and you still have the original tail, here is my recommendation for making the plane more responsive.

Move the control lines to the bottom holes, then retrim the tail. Do not remove the tail in the process. Move one side, then retrim, then move the other side and retrim, then check them both for trim.

The screw/adjuster should have come from the factor in the next to the top hole. That is where it should stay. Some people mistakenly moved the adjuster, instead of the line.

Does the boom move at all. While it will flex, it should not move inside the pod. It should be solidly attached. Go to the back of the tail. Thre is a black collar on the boom where the orange V brace mounts. Is that color solidly attached, or can it rotate left or right. If it moves, it will diminish the effectiveness of the stick inputs you give it.

Do these. See how she flies. If you still have the original tail, get yourself an X Pack with the more responsive tail and the 7 cell battery. Or just get the tail for the new Aerobird Challenger. It is the same as the tail in the XPack.

Let me know how it goes.