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View Full Version : In praise of Elapor foam!


rcommo
11-25-2006, 07:12 PM
Well, it was 34 degrees, but there was no wind and occasional blue patches could be seen in the sky. So off to the field I went, figuring it would be all mine. The field was empty, which turned out to be a good thing.

I put on the wings of the Easystar; fired up the Tx; connected the battery and stuffed it into the front the plane. This where the CG came out perfectly the last time. Check the CG and the tail is dropping a couple of inches. Ouch! Put the battery as far forward as it would go – only helps a little.

Geez, who’da thunk that a piece of balsa (for the new, bigger rudder), control horn, linkage and painting the whole empennage would have such a drastic effect on the CG!

Hmm, what to do? If I go home it could start raining. And then there’s the honey do list. At this point testosterone kicks in – clear thinking kicks out!

Oh, what the heck, I’ll give the plane a toss – it’ll just porpoise around a bit till the elevator is trimmed. The bird is put on the ground and all control surfaces and the throttle are checked. Ok, it’s ready to go.

So I open up the throttle and give it a level toss with neutral elevator – after all I know the tail is a little heavy.

Yoiks! It heads up like a rocket; but a stock Easystar isn’t powered like a rocket. So right goes right into a stall. Ok, take a deep breath, let it head back down, straighten it out and then trim in some down elevator.

Oops – the plane just makes a fairly nice “U” and heads into another stall. It’s also rolling a bit – but hey – the new large rudder is handling that like a champ. Now if I can just get the elevator trimmed…

Well, after dialing in as much trim as the DX6 will give it the plane is still porpoising around like it belongs in Puget Sound!

After fighting this for maybe a minute or so I kill the motor - at least lower down the speed of the the crash. It starts the glide – at, maybe 20 feet and heads straight up again, stalls and then heads about vertically into the ground nose first.

Didn’t like that crunchy sound, but only saw the canopy pop off – nothing else flying off. I can only see two pieces – the whole plane and the canopy about 5 feet away. This as a good sign - shouldn't have too much repair work.

Walk across the field to retrieve the plane and inspect it. Expectations are that the body behind the nose will be, shall we say, widened a bit. Or perhaps the nose will be jutting away from the body at an odd angle. Nope, what I see is the top of the nose is split along the seam. Looking inside the electronics bay perhaps it was trying to do the same along the bottom seam too; but the reinforced packing tape held it together. Looking a little more closely at the open seam I see that the two halves of the body are held together with only double sticky tape.

The walk back is filled with regret that I hadn’t thrown my “adhesives kit” into the van. Even at that, the day could have gone on if I had remembered to put the packing tape back into the flight toolkit.

Rats! I had stuff I might have been able to use as ballast. But now, the only thing to do is to head back home and face the day’s tasks.

Tomorrow may see some of Seattle’s hilly areas covered in light snow! At the minimum there will be a lot more rain from another storm coming in off the ocean.

Turning lemons into lemonade, the big question becomes, “if the body is split open a bit anyway should I use it as an opportunity to swap in a brushless inrunner, change over to a new ESC and LiPo?”

The big lessons learned today.

Always check the CG after any changes the plane, even seemingly minor one.
CG matter.
CG really, really matters.
If the CG changes much at all pretend this plane is broken and go fly another one instead.
Make sure you head out to the site with everything you need.
Add some “split-shot” to the flight kit – worst case it can be taped onto the body where needed to restore the CG to where it should be.-rick