Sport CARF Pitts - Engine Upgrade

[reyn3545]

After further review.. I think I'll just move the batteries.

I was able to remove the original battery tray from its footing and shift it back to sit on a fuselage brace that runs across the back of the plane. A quick CG check tells me that with this shift, the CG is now 2 inches behind the leading edge of the plane. The previous setup had the CG at 2.75 inches. On a lot of planes, 3/4 of an inch would be a lot, but on this behemoth, I don't think I'll notice it. If I do, at least it will be a forward CG, and I can always add weight if I want to later.

 

[dhal22]

I've seen batteries deep in the fuse to avoid lead in the tail.

 

[reyn3545]

These are about as far as I can reach now... If if was a wooden plane, I'd cut an access hatch in the bottom.

 

[dhal22]

Duct tape them to the tail?

 

[reyn3545]

Now, there's a thought!

Sent from my XT1080 using Tapatalk

 

[Jetpainter]

Now, there's a thought!

Sent from my XT1080 using Tapatalk

It would work for Red Green! Or the Mythbusters.

 

[dhal22]

These are about as far as I can reach now... If if was a wooden plane, I'd cut an access hatch in the bottom.

There is a thread 'elsewhere' showing cutting servo hatches for ailerons in Carf planes. Someone was doing a pretty neat job of that.

 

[reyn3545]

I cut servo holes in the wings of a previous planes, and on this one I moved the elevator and rudder servos to the back, cutting holes and adding backing plates for support. And it still needed more tail weight! This plane was designed back when a DA150 was a big motor.

 

[dhal22]

Finally I'm switching to modern Fromeco batteries and removing my Nimh batteries from my Yak. With the heavy 3W up front they worked well for helping with balancing. I will have to move the newer lighter batteries further back.

 

[reyn3545]

A123's make a world of difference for charging, no explosion danger, and they are very reliable... You just need to proactively charge them after every 3 or 4 flights. For me... that's just about a day's worth of flying.