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        Discussion Wild Hawk First Flight - Not so good.......

#1 Bob6831 Oct 31, 2012 04:13 PM

Wild Hawk First Flight - Not so good.......
 
Well, I finally put my plane together, made sure the rudder and elevator were about in the centerspots by turning the pushrod screws (had them in center hole), and adjusted my CG (by using a stack of quarters in the front compartment), such that it was just in front of the front tube indentation in the wing..... which is about 2.25 inches from front of wing.
Did a quick check on the CG by launching my plane in the front yard with no nothing turned on. It kind of nosedived, but removing a few quarters seemed to help.
On to the real attempt........ turned prop on, made sure elevator and rudder worked first and then hand launched with the motor about 3/4 power. Only went a few yards and then kind of nose dived even though I had moved the elevator control up........ Tried a few times with similar results (tried almost full speed). Last time nosedived with upturn and broke the rudder off of the base.
So........ what am I doing wrong and should I fix the rudder back on with some tape or should I do the hinge route?
Also, maybe I should make my rudder and elevator wider with some styrofoam?
Thx
P.S. Wasn't any wind problem.

#2 dedStik Oct 31, 2012 04:40 PM

What was the angle you launched it at? Also you can avoid having to add so much weight to balance by moving the weight further forward. The closer to the nose the less weight it will take to balance.

This plane should probably be launched into the wind or near as, and at an angle.

Were your controls going the right way, pulling back on the stick elevator goes up? If the controls were reversed I could see this happen. Or if you don't have enough surface throw.

#3 whitecrest Oct 31, 2012 04:52 PM

Double check the instructions for correct CG location. If this is a stock setup, it should probably balance correctly without any additional weight, unless you're using a very light battery. Try shifting the battery forwards or aft to get the correct CG. The less ballast required the better.

When hand launching, toss it horizontally into the wind. This will allow the plane to gain flight speed quickly and avoid stalling. If you throw it too sharply upwards, it will likely pitch up suddenly, stall, and nose in.

#4 bartricky Oct 31, 2012 05:01 PM

The Hawk will want to dive until it gets up to speed. Give it a healthy toss to gain speed. Like you are throwing a 10 yard pass.

CG should be on the spare cover.

#5 Bob6831 Oct 31, 2012 05:49 PM

Thx for the replies, but don't understand a few things:
You say CG should be on the spare cover - you do mean SPAR cover, correct?
I had the CG about 2.25 inches back from front wing edge...... where do you believe it should be?
Transmitter was set to Normal, not Reverse, and I launched it at about a 10 degree angle upward.
Maybe I didn't toss it hard enough?
Is there an advantage to moving the battery forward (would need to cut foam divider out between battery compartment and forward compartment ) versus adding weight to front end like I did?
Thx.

#6 bartricky Oct 31, 2012 06:35 PM

Quote:

Originally Posted by Bob6831 (Post 23150266)
Thx for the replies, but don't understand a few things:
You say CG should be on the spare cover - you do mean SPAR cover, correct?
I had the CG about 2.25 inches back from front wing edge...... where do you believe it should be?
Transmitter was set to Normal, not Reverse,
Thx.

Yep spar cover..
Set it up by which way the control surfaces move and not what the Tx says.
Stick back... elevator up.
Stick right... rudder right (looking from the rear)

and try more power.

#7 Bob6831 Oct 31, 2012 07:30 PM

elevator and rudder move in the right direction.... how about my CG questions?
and glue and more rudder area?

#8 bartricky Oct 31, 2012 08:12 PM

Quote:

Originally Posted by Bob6831 (Post 23151020)
elevator and rudder move in the right direction.... how about my CG questions?
and glue and more rudder area?

My CG is 2.5in back.. you should be good.

#9 tacx Oct 31, 2012 09:54 PM

Make sure your prop is tight on the motor shaft. If it is slipping it will sound like it has power when actually you don't have enough.

You have to give a real good toss. It won't fly until it gets enough speed.

I believe the Wild Hawk is a EZstar clone and you should be good at 1/2 to 3/4 throttle. On the EZ, and I assume the Hawk, the motor pod is angled down. I had trouble with my EZstar because I was launching at full throttle and without enough speed at launch the motor would drive the plane down.

As far as your rudder goes just use some packing tape or Hinge tape (also called "Blenderm") to reattach the rudder.

#10 Bob6831 Oct 31, 2012 11:09 PM

Thx for all feedback,
Still looking for answers to my CG questions.... whether is any better to move the battery forward vs putting weight in front compartment..... sounds like it might be because overall weight of plane won't be as heavy.

#11 whitecrest Nov 01, 2012 04:09 AM

It's better to not have to add extra dead weight. A lighter plane will generally fly better. If there's room to shift the battery forward or aft to get the right CG without doing major surgery, that would be the preferable option. It will probably balance correctly if set up as illustrated in the manual.

Another thought is to make sure the prop is oriented correctly. Usually, the numbers printed on the prop (indicating diameter and pitch) should face forward. If the prop is on backwards, you'll get much less thrust because the prop's airfoil is not "flying" in the right direction.

#12 jrtubb Nov 01, 2012 11:23 AM

Agree adjust battery forward and remove the extra weight if possible to get CG correct. I noticed you didn't mention checking wind direction and launching into the wind. This will make a big difference, make sure you are not launching with a tail wind.

#13 fastfwd Nov 01, 2012 01:37 PM

1 Attachment(s)
few other random thoughts, prop isnt on backwards is it ? elevator does move UP when you pull down on tx stick ? here is a good pic of correct prop install

#14 alibongo Nov 01, 2012 05:53 PM

Nose heavy, the plane will fly enough to make it back to be trimmed.Tail heavy, the plane won't make it back.Hand launches should be three-quarter throttle, level or very slightly nose down to allow plane to gain speed.Once it is up, get enough height to avoid the ground and give slight but sufficient control imputs to get the plane to circle.On landing, try to land near youself so you can see what is happening, and close throttle and flare just before touch down.After your first successful flight, you'll gain more confidence.other people may give you better advice.
Suddenly it will "click" and you will find you can control your plane.Thereis always something new to learn, but suddenly to find you are controlling your rc plane, not the plane controlling you, is a great moment.

#15 FlyBoy20 Nov 01, 2012 07:42 PM

I'm just newbie, but for the HK J3 Mini Cub I kept tossing into the ground until I tried full throttle with a vigourous chuck into the wind. Some planes have high wing loading and won't just float away with ease.

Rule of thumb for CG is 1/3rd back from LE.

Also, try setting low values for dual rates, initially..I used 35% with 15% expo!


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