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Old Jul 13, 2009, 09:00 PM
If I yell "look out" I mean it
gpierson's Avatar
Joined Jun 2009
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Easy Star Weight Issue

A newbie Easy Star learner here...I'd love to hear some of your thoughts on this.

I still have my Easy Star with stock motor. When I first flew it, I ran it with a 7 cell Nimh, 1100 mah. Flew fine with relative ease in low wind, but very short time.

So I decided to buy a 2 cell lipo 2100 mah. Wow, long and powerful run time BUT I totally threw off the weight. I was able to move the battery all the way foward in the compartment to get good COH. But here's the kicker.

It weighed in at 21 ozs. I figured "Great! Now I'll be able to stay up even longer with low weight."

So I went back out to fly...and total confusion and chaos. It was EXTREMELY sensitive to any little rudder/elevator movement and any little wind. Granted, it was a little windy, but not bad.

I was ready to give up, very frustrated. Lost the plane down wind 400 yards away - TWICE. Before I left, I had a thought and decided to throw some weight in there for the heck of it. I didnt have anything so I put in 4 AA alkaline batteries at 3.3 oz. Got COG correct. And whalla!!! it was flying relatively smooth again. (Until I crashed it by going full throttle when I meant to push up on the elevator right before a landing...broke in half, but glued back together.)

I'm going out again tomorrow. I'm gonna put in some lead tape at approx 3.3 ozs.

Anyhow...all that to say, I see WEIGHT is critical for 1. slight breeze. 2. a newbie like me. 3. more control.

Please give me some advice: 1. In general, does a particular airplane design have a goal for weight? 2. Is 21-23 oz too little for easy star? 3. What is the best weight to acheive for a learner like me - even in little to no wind. 4. Is is critical to get the weight at the bottom of the compartment? (thereby getting the weight to lowest part of the physical plane? 5. How do I keep doing this without getting my wife jealous? (I'm starting to wonder if she's going to hide the plane from me!)

Thanks to all in advance.
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Last edited by gpierson; Jul 13, 2009 at 09:06 PM.
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Old Jul 13, 2009, 09:52 PM
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Joined Jul 2008
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That last question is an impossible one to answer

The others you seem to have the right ideas about. The lipo being lighter threw off the CG which in turn caused the twitchieness (sp). The AA's brought the CG back to where it should be and the handeling returned. Being slightly nose heavy is OK for the EZ*, as you get more confortable with it you can move it back by reducing the balast and the plane with glide further and have a lighter wing loading.
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Old Jul 13, 2009, 10:15 PM
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South Carolina
Joined May 2009
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Easystar needs and likes a lot of weight with lipos. With just a 2s 2100mah lipo it will go up and right back down on it's nose.(too lite) Try it with the 2s 2100mah lipo AND the nimh pack inside(with only the lipo hooked up of course)and see how good it flies. thne just equal the weight by adding filler weight wrapped in foam to equal the nimh pack when u take that pack out. and make sure nothing is sliding around while flying will throw off cg.
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Old Jul 13, 2009, 10:57 PM
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53859 Niederkassel, Germany
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Quote:
Originally Posted by gpierson
...
Anyhow...all that to say, I see WEIGHT is critical for 1. slight breeze. 2. a newbie like me. 3. more control.
...
1. Weight is not critical, but CG is, especially for a newbie.
2. Wind is usually not a problem, unless you have a lot of turbulence.
3. More weight means faster glide, hence more response from rudder and elevator, but also more damage in a mishap.

Jürgen
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Old Jul 13, 2009, 11:12 PM
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Joined Oct 2007
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Really, you should be able to put in a 2S 3200 mah pack and keep the CG the same.

With a more rearward CG, which the Easy Star does not like, the control inputs on the tail become very sensitive, which is why 3D pilots tend to put the CG towards the aft end of the CG range (most normally balance the plane so it flies upright and inverted with no elevator input).

You will find that being slightly nose heavy dampens the control inputs a bit so it make it much more stable.
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Old Jul 14, 2009, 05:17 AM
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Quote:
Originally Posted by gpierson
.[/B] I was able to move the battery all the way foward in the compartment to get good COH [CoG].
For your purposes the CoG has to be perfect. 'Good' in this context is the same as being wrong.
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Old Jul 14, 2009, 09:11 AM
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53859 Niederkassel, Germany
Joined Sep 2000
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Quote:
Originally Posted by gpierson
...
Please give me some advice: 1. In general, does a particular airplane design have a goal for weight? 2. Is 21-23 oz too little for easy star? 3. What is the best weight to acheive for a learner like me - even in little to no wind. 4. Is is critical to get the weight at the bottom of the compartment? (thereby getting the weight to lowest part of the physical plane? 5. How do I keep doing this without getting my wife jealous? (I'm starting to wonder if she's going to hide the plane from me!)
...
1. No, there is usually not a "goal weight", but a weight range. Apart from weight differences in the foam parts, it largely depends on what equipment you install in your model.

2. Initially my EasyStar was less than 20oz with two Hitec HS-55 and a Mabuchi RS-370.

3. Lighter is better, as it will fly slower and survive hard landings with less damage.

4. No, it is not critical. Correct CG position is much more important.

5. Stop teaching your girlfriend flying the EasyStar.

Jürgen
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Old Jul 14, 2009, 04:47 PM
If I yell "look out" I mean it
gpierson's Avatar
Joined Jun 2009
626 Posts
an update...I flew early this morning in almost no wind. I moved the battery to make it more nose heavy. even just moving it 1/2 inch made a world of difference. It flew much smoother and controlled for me now. Now I see its pulling right because of a bent fuse from a not so perfect glue job.

Any suggestions on straightening it? hot water?

I'm guessing a heat gun set on low...
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Old Jul 14, 2009, 04:53 PM
If I yell "look out" I mean it
gpierson's Avatar
Joined Jun 2009
626 Posts
Also, thanks for the advice on the wife problem.

If it turns out I'm teaching a girlfriend how to fly I'm certain my wife would destroy the plane.

So I guess I should stop teaching her if I want to keep the plane
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