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Seagull Edge 540 (160) CG Crisis

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Seagull Edge 540 (160) CG Crisis

Old 10-09-2011, 11:24 PM
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RappyPilot
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Default Seagull Edge 540 (160) CG Crisis

Hi all

I have just built a Seagull Edge 540. The big 160 size pearl blue one. I have an OS160FX in there with a Bisson Pitts muffler. Batteries, RX everything mounted as far forward as possible.

They say the CG is 95mm to 110mm from the leading edge of the wing. But after putting in a whopping 250 grams of lead as far forward on the firewall the plane is still tail heavy and now balances about 125mm back from the leading Edge. Seems like I am going to have to add another 250 odd grams to get it to balance, totalling just about half a kilogram of dead weight!

If anyone out there has this plane, where does yours balance and how much dead weight did you have to add?

Marcel
Old 10-10-2011, 05:01 AM
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RCVFR
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Default RE: Seagull Edge 540 (160) CG Crisis

That looks like a mistake. Balance on the wing tube for starters and adjust from there. The wing tube location is generally at or near the wing's center of lift, and that is where you want the balance to be. Good luck.

EDIT: One other thing, sometimes Seagull will give the balance point out on the wing tip, rather than the root of the wing. I have a Seagull YAK 54 that is that way. On mine, I mounted the wings on the tube (but not on the fuse) taped a string at the indicated position, stretched to the other wing tip and noted where the string crossed the root. It came out just aft of the wing tube. My YAK flies wonderfully at that balance, just a touch nose heavy.

Old 10-10-2011, 09:36 PM
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Default RE: Seagull Edge 540 (160) CG Crisis

Hi

Thanks for that, you have just confirmed what that little voice in my head was saying all along. At the moment it balances far behind what manuals recommended CG but it does balance just in front of the wing tube. Which "feel and looks" better. I am oping the manual is wrong and that I might me able to remove some weight. But as long as the initial flight and setup is done and she is not horribly tail heavy I will be happy.

An Edge 540 does not have a tapering edge so balancing it on the root of the wing or the tips (As you, as my manual suggest does not make a difference)

Anyway, hold thumbs, she is ready for her maiden this weekend ...
Old 10-11-2011, 01:51 PM
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Default RE: Seagull Edge 540 (160) CG Crisis

I flew the smaller (60/90) Seagull Edge for a couple years and as I recall, that one also balanced just forward of the wing tube. Should be good for a start. Best of luck with the maiden.
Old 10-17-2011, 01:21 AM
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Default RE: Seagull Edge 540 (160) CG Crisis

Hi guys

Wel, had a sleepless night on Friday in anticipation of maidening her.

As you can see she flies! I must say, the manual is WAY out as far as the CG and control throws is concerned.

But, with the CG being just in front of the wing tube, and the manual's recommended control throws disregarded and the plane set up according to "gut feeling", initial test flights went without a glitch.

I was surprised how much she floats when coming in to land, I had to go around 3 times because she just does not want to land.

This is really an awsome plane.
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Old 10-17-2011, 04:15 AM
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Default RE: Seagull Edge 540 (160) CG Crisis


Old 10-18-2011, 11:58 AM
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Default RE: Seagull Edge 540 (160) CG Crisis

I have just had the same issue with a Cap 232 I got from E Bay its exaxtly the same Size as the Blackhorse 180 80" but rather than Blackhorse C of G being 150mm to 160mm this one was 133mm to 143mm, making it stupidly tail heavy. I too headed for the main spar which was 155mm and it was perfect, it's worrying that we are left guessing the C og G by the makers, someone who types the manuals must be just having a laugh at our expense. Many youtube crashes show models set to manuals C of G only for it to be miles out


Old 12-07-2020, 05:50 PM
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Default Seagull Edge 540. V2

So I had just bought the seagull edge 540 V2 I took the pilot out and I'm still adding a pound and a half of weights does anybody know exactly where the CG mark would be? I put a dle 35ra in it. I have a 17 Oz extreme flights gas tank near the CG empty. I read some threads to say start at the wing tube. I never had an ad so much weight to a plane don't know what to do can someone help me
Old 12-07-2020, 06:00 PM
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Jepsterdav
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Default Seagull Edge 540. V2

So I had just bought the seagull edge 540 V2 I took the pilot out and I'm still adding a pound and a half of weights does anybody know exactly where the CG mark would be? I put a dle 35ra in it. I have a 17 Oz extreme flights gas tank near the CG empty. I read some threads to say start at the wing tube. I never had an ad so much weight to a plane don't know what to do can someone help me
Old 12-08-2020, 05:23 AM
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ahicks
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Default

There is no "exact" with CG. Each flyer's will be a little different, especially those with more experience. I would start on the front side of the wing tube for my maiden, then trim as necessary from there.
Old 12-14-2020, 08:11 PM
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warhwk
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Just to confirm what others are saying... Balance on the wing tube then adjust to suit your flying style.
I slowly moved the CG back until it would Knife-Edge w/o pitch coupling.
BTW, this Edge has the least unwanted coupling of any plane I've ever flown.

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