Krill Spark Build questions

[rmarsden]

	Quote: Originally Posted by 1bwana1
	Randy, That thing is not done yet??? If you want to see a live D.E.P.S system, my Passport is set up this way.

Steve,

The research is as much fun as the build. Plus I need to work on the ZN too.

[joenella]

	Quote: Originally Posted by rmarsden
	Thanks RV-8. So, where is your CG now, relative to the wing tube? This is my first pattern plane. I have 25% and 35% IMAC planes and am in the process of building a 40% ZN-Line Extra in addition to a 'few' smaller planes. My new Spark does not have a counter balance on the rudder as shown in most pictures of the Spark. Does your have counter-balance on the rudder?

Spark version 2009 DOES not have the counter balance on the rudder, so you got the newest version

I fly both version 2008 and 2009 and the 2009 flies a few percent better.

My CG i just 15 mm ahead og wingtube center.

[RV-8]

	Quote: Originally Posted by joenella
	Spark version 2009 DOES not have the counter balance on the rudder, so you got the newest version I fly both version 2008 and 2009 and the 2009 flies a few percent better. My CG i just 15 mm ahead og wingtube center.

Hi Guys

Sorry I have not posted in a while but I was called out on a flight and have been away for 6 days. The plans on the net show the C/G 30 mm forward of the wing tube. When I first built my Spark I had the batterys all the way forward just behind the motor and the lipo for the rx also right at the front, even then I could not get the plane to ballance, ie I was still tail heavy. I thought I would fly it and then take the two elevator servos out of the tail and replace them with a single servo in the fuz. The C/G just did not look right it was about 10 to 15% MAC most pattern ships are 25 to 30% MAC. Well my first test flight confirmed my fear, the plane was WAY nose heavy. On an inverted 45' up line the plane would immediatly pull to the canopy. I then on subsequent flights just added more and more lead on the tail until I got a C/G that I was happy with. It it quite a bit further aft than the plans. I then had to cut out my bat tray and relocate the motor batts to more or less over the landing gear. I aslo moved the receiver bat rearwards and placed it next to the rx.

At the moment if I leave the wings and canopy OFF the fuselage and every thing else on (stabs, batts, prop, spinner, ie ready to go) and pick it up by the wing tube the fuselage hangs slightly tail down. This will be a good place for you guys to start and you can fine tune it from there. Next time i go practise I will balance it with the wings on and let you know.

I have included some photos for you guys of my set up. hope it helps

[asleep]

Hi Rv-8,
thanks for the pics. Say, how much right thrust have you settled on?

cheers

- j

[jonigira]

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