ELAN C of G.
#1
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From: Cheshire, UNITED KINGDOM
Was hoping to maiden my Elan Tomorow, but can somebody answer my c of g qestion.
I have taken my measurement from the trailing edge at 250mm.
But the only way I can get it to balance there, is to have both my ECU battery(4300 N-Mh) and my Flight Pack Battery (3000 Ni-Mh), close to the centre section of the Fuselage.
I am sure my position is OK, Just seems unusual to have no Batteries up in the forward section of the FUZ.
Hope Alan can answer this before the morning!!!!
Thanks
Peter
P.S
Its a P80 in the back, and tank is empty.
I have taken my measurement from the trailing edge at 250mm.
But the only way I can get it to balance there, is to have both my ECU battery(4300 N-Mh) and my Flight Pack Battery (3000 Ni-Mh), close to the centre section of the Fuselage.
I am sure my position is OK, Just seems unusual to have no Batteries up in the forward section of the FUZ.
Hope Alan can answer this before the morning!!!!
Thanks
Peter
P.S
Its a P80 in the back, and tank is empty.
#3
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From: Cheshire, UNITED KINGDOM
P80 Turbine, so it is well within what It is designed for.
I am sure its OK, I just want t get some feed back, in case I am missing something??
I am sure its OK, I just want t get some feed back, in case I am missing something??
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From: Prescott Valley, AZ
I'm glad to hear that your Elan didn't come out tail heavy - I had to add 8.5 oz of lead to the nose of my baby boomer to get the CG right. Since I'll be using a Wren SS on my Elan (slightly lighter than the P80), I might have to use heavier servos in the tail to get it balanced. (Which I prefer to adding lead in the nose...)


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From: Nordborg, DENMARK
Just finished mine tonight. A 4 cell receiver battery pack and a LiPo for the turbine. The CG is right on the 250 mm dot with the batteries in the nose and empty tank. Mine has a Simjet 2300 for power.
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From: Rossmoor,
CA
ORIGINAL: Stig Andersen
Just finished mine tonight. A 4 cell receiver battery pack and a LiPo for the turbine. The CG is right on the 250 mm dot with the batteries in the nose and empty tank. Mine has a Simjet 2300 for power.
Just finished mine tonight. A 4 cell receiver battery pack and a LiPo for the turbine. The CG is right on the 250 mm dot with the batteries in the nose and empty tank. Mine has a Simjet 2300 for power.
THANKS, LUIS
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From: Nordborg, DENMARK
ORIGINAL: mowery1
What retracts did you use in the ElAN??
What retracts did you use in the ElAN??
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From: Nordborg, DENMARK
ORIGINAL: Hornet 1
ANY TIPS OR ADVISE ON ANYTHING FOR THE ELAN BUILD?? WAS EVERYTHING PRETTY MUCH STRAIGHT FORWARD??
THANKS, LUIS
ANY TIPS OR ADVISE ON ANYTHING FOR THE ELAN BUILD?? WAS EVERYTHING PRETTY MUCH STRAIGHT FORWARD??
THANKS, LUIS
My SimJet engine is a little big for the Elan, so it required a little modification of the formers, but otherwise it was straight forward.
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From: Cheshire, UNITED KINGDOM
Here is a picture of the Turbine Position, Just wondered if I could get away with moving my Turbine further back to help?
, I am using a 4300 Ni-Mh pack for the ECU, (v heavy), and a 6 cell 3000Ni-Mh pack for radio.
The ECU Battery is under the Tank, and the Flight Pack is in between the Front of the Tank and the front of the Tank.
Just seems unusual to have no batteries in the nose. C of G is at 250mm from T edge.
, I am using a 4300 Ni-Mh pack for the ECU, (v heavy), and a 6 cell 3000Ni-Mh pack for radio.
The ECU Battery is under the Tank, and the Flight Pack is in between the Front of the Tank and the front of the Tank.
Just seems unusual to have no batteries in the nose. C of G is at 250mm from T edge.
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From: Northamptonshire , UNITED KINGDOM
Hi Pete
Yep this is about right. Alan designed the Elan with the long nose and short tail to try and get round the need for having any extra weight up front. Our demo model with the supersport in it started off with the rx pack and the lipo up front but I found this to be too nose heavy so we gradually moved them back to the centre section of the fuselage. My thoughts on C of G on a plane like this is that you really do need to play with it a little to fine tune the plane to how YOU like it. Start with it slightly nose heavy and see how you go.
Regards Al
Yep this is about right. Alan designed the Elan with the long nose and short tail to try and get round the need for having any extra weight up front. Our demo model with the supersport in it started off with the rx pack and the lipo up front but I found this to be too nose heavy so we gradually moved them back to the centre section of the fuselage. My thoughts on C of G on a plane like this is that you really do need to play with it a little to fine tune the plane to how YOU like it. Start with it slightly nose heavy and see how you go.
Regards Al
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From: Nordborg, DENMARK
ORIGINAL: Synthetic
Stig,
What thrust is your Simjet and what fuel tank is that?
Thanks,
Don
Stig,
What thrust is your Simjet and what fuel tank is that?
Thanks,
Don
Sorry for the late reply. I've been away for a jetmeeting this weekend. I flew my Elan 8 flights and it flies REALLY GREAT. This thing is on rails. I'm going to move the CG a bit forward. It is my personal prefference because I like my planes a bit nose heavy for safety reasons.
Anyway.
The Simjet 2300 i rated at 25 lbs of thrust and I have a 2-litre fuel tank. I think that I will mount a Simjet 1200 rated at 18 lbs to get better fuel economy and lower weight. It really does not need all that power...... With the 2300 I never got over ½ throttle.



