I have a Spitfire with a Super Tigre 90 in it and it's almost ready for testing but before I do I wanted to know the easiest way to get a rough idea of the C of G. Can anyone help with this?
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If you want just a "rough" idea, the rule of thumb is a good place to start ......................... 1/3 of the wing cord at the wing root from the leading edge. A more precise CG recommendation would be what the manual says. -
I have the same model and I balanced per the plan. It took about 1LB of bee bees to balance came out to about 10 1/2 lbs. Used the great plains cg machine to balance the model.Comment
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I checked the balance point on my plans and it is about 4" from the leading edge of the wing. I usually fly my models aa little nose heavy for the first flight and then adjust from there. Currently this model is not flying but still in one piece lol. The graphics are from Callie and the model marking are of Bill Dunn an ace in eagle squadron (American volunteers in RAF)during the battle of Britain. I had the opportunity to meet him many years ago, quite a guy.Comment
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I have no plans as the plane was given to me through a friend of a friend.
The wing measures about 355mm from the leading edge to the trailing edge and so far I decided to measure 127mm back and I had to add 675g of lead to the nose. I am a competent flyer and so if you think this is a good starting point then I should be fine.
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Hello dilligal76 127mm is about 5" that may be a bit too nose heavy but should work. This model needs that big engine to fly right a 65 will not give it enough power. Keep the speed up when your landing and use full flaps. I hop all goes well on the maiden flight it looks great in the air.Comment
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Unfortunately no flaps or retracts installed on this plane which is a bit of a downer but we can't have it all I guess...
What do you mean the bit about (This model needs that big engine to fly right a 65)?Comment
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The plans call for a 60 to 90 size engine for this model and because it tends to build heavy (10lbs or more) the smaller engines do not have enough power to fly it properly. If you fly off of a grass runway depending on how it is mowed you need all the power you can get to get it airborne. No flaps will make for a hot landing so I hope you have plenty of runway. There is a good thread on this model on RCscalebulder.com that would be a great resource for you. You may have to register on the site to gain access.Comment
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Okay I see and I agree with what you're saying about the engine size and build. It is a well built plane unlike some of these artf's you get from model shops and it's always better to have more power rather than it be under powered. It has a Super Tigre 90 in so it should be okay. If I had something like a 120 I would have put that in.
Where I fly we have a nice long tarmac runway so take off and landing it will be fine. Luckily I am used to high speed landings as I have a Velocity from Weston UK which is fun. Thanks for the link too I will have a look...Comment
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Anyone know where an actual CG balancing tool can be acquired...?Comment
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Not sure where you can get it but I've used this for decades.
Great Planes C.G. Machine Precision RC Aircraft Balancer : Toys & Games (amazon.com)Comment
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The first RAF Eagle Squadron, No. 71, became operational on 5 February 1941, after the Battle of Britain was over.
The nine American pilots who participated in the BoB flew in regular RAF squadrons. They risked prosecution and loss of citizenship back in the US for violating US neutrality laws.Comment
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I have three, including the fancy big yellow monster, but my favorite is the CrewZinn airplane stand and balancer.
It's turned out to be the handiest item I have.
Grossman56Team Gross!Comment
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So I wanted to try the Spitfire out today but I couldn't find anymore weight except for 100g more to add to the nose and I went with that.
So with 775g of lead to the nose in total at about 120mm from the leading edge and it seem to fly well although I had to trim a fair bit of up elevator in so perhaps it's still a little bit too heavy on the nose?Comment
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Congratulations on your maiden flight!! You may want to take out a little weight from the nose that should help on the elevator trim. How did it land for you?Comment
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As I've stated before, I have 70 gm just forward of the battery tray and fly with my Admiral 4500's all the way forward and she flies beautifully.
There were a handful of us worldwide that had Spitfires that, for some reason were usually tail heavy. This worked great for me as before I was lucky to land without breaking out a retract.
Now she handles great!
I maintain 25% throttle and full flaps on landing and that's usually within a click of the needed throttle to walk her in. I set my timer to chirp at 25% so I had an audible when I'm at the correct setting.
Grossman56Team Gross!Comment
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Thanks, I 'll take off a little bit of weight and try it again. The landing was fine really, didn't bounce and didn't travel that far once on the ground although there was quite a bit of head wind which helped with that, I can't wait to try it again once I've ironed out a couple of other minor issues....Comment
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Well done team Gross, sounds all good to me!As I've stated before, I have 70 gm just forward of the battery tray and fly with my Admiral 4500's all the way forward and she flies beautifully.
There were a handful of us worldwide that had Spitfires that, for some reason were usually tail heavy. This worked great for me as before I was lucky to land without breaking out a retract.
Now she handles great!
I maintain 25% throttle and full flaps on landing and that's usually within a click of the needed throttle to walk her in. I set my timer to chirp at 25% so I had an audible when I'm at the correct setting.
Grossman56Comment
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That's great dilligaf76 not many of those top flite models around anymore. I hope you have many more successful flights on the spitfire.Comment
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