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Old Today, 04:01 PM
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acesimmer's Avatar
United States, NV, Fernley
Joined Oct 2011
1,997 Posts
Thanks all for the encouragement. Had a friend over to help me with assessment and have found the issues that caused the crash.

We setup V1 per Vegas last year and V2 per yesterday flight mode. Tested every control throw against V1 and they matched exactly. However, we got a shock when checking the CG. On V1 it was nose heavy on the CG marks that Nut and myself did after last years test flight with gear down

. Then we moved forward of the CG mark 3/8". The bugger dropped its tail like a sledge hammer!!. Then back to the original and it was nose heavy. We repeated with the gear retracted and it became neutral with just a slight forward tip. So on V1 the CG is super sensitive which was a bit of a surprise.

Repeated with V2 on the same CG positions. Sure enough just removing Biggles the pilot dropped its butt and hence tail heavy. I had also shifted the bats rearward about an inch so the cockpit tub would clear the batteries in the V2 design. So Biggles became the difference between semi success and total failure. I guess one should not fly a plane without a pilot. V2 canard servos are 10" more forward than V1 and I figured this would shift the balance quite a bit. Prior to the test flight V2 seemed super nose heavy and the reason I removed the pilot. Bugger me sideways, that made the difference!! Now if I had managed to get off the deck and in flying mode then retracting the gear would have had a serious tail heavy condition that would have surely written V2 off. So all said and done I was lucky to crash it the way I did. Lesson learned with these Delta/canard setups is to be nose heavy.

Damage Report.

Not so bad than what it first looked like. Stress cracks can be easily repaired in a couple of hours with resin and 3oz cloth patches. Then filler sand and blend paint. Right main gear totally busted along with the nose gear. Struts are perfect and will reuse. Nose gear box had the ply delaminate in a weak spot on one side. Some CA a clamp then a compression plate epoxied to the inside will sought that out.

The wing cracks are solid due to the outer panels being just foam and where slightly sprung but retained the original shape and still very strong. Does not look like any damage to the main wing spars and mount areas. Fans and internals are solid and did not move. However, I'll remove the fans and clean them out. So before repairing the cosmetic wing damage I'll re-test fly and if good then fix the cosmetics for vegas.

For both variants I will be placing the canards on a three way switch with an over ride trim function from the elevators trim. Position zero they will be disabled if required. Position one will reduce the throw to around 40% for takeoff/landings and normal flight. Position three will be full deflection for aerobatics and aggressive flying

So far looks like it will be okay.........
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Old Today, 04:11 PM
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DamonH's Avatar
United States, NM, Clovis
Joined Oct 2011
3,168 Posts
Glad to hear you figured out the issue Ace and that the damage isn't as bad as you initially thought. Hopefully you'll have it flying soon....I'm really looking forward to seeing this beauty in the air.
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