wilco3

When test flying a Long EZ it dropped it's nose and went in. I've got the C of G where recommended, possibly a bit further forward for what I thought was safety. With canard planes is it better to move the C of G back, (less weight in the nose) ???? Any other reasons or suggestions why the front wing would stall on take off ???

jetmech05

tell us more, were you at full throttle? during take off? with the wind etc.
without the details kinda hard to tell
CG out of range, wing or conard incidience incorrect, or it stalled are all possibilities

RCKen

My Feedback: (9)

Did you balance it with fuel in the fuel tank? With a plane that has the tank aft of the CG point needs to have the tank full when you balance it. If you balanced the plane with the tank empty it could lead to a severly tail heavy plane when you fillt he tank, and this could have caused your loss of control.

Ken

MajorTomski

Well, a well designed canard the canard will stall first. With a forward CG it is going to stall sooner than it would have had the CG been where it belonged or aft of that point. And like any wing once stalled it isn't going to do its job untill it's flying again. You may have done what most of us do, hold full up trying to recover, which would not have let the canard become unstalled and it couldn't fly, so it couldn't pull the nose up.

Moving the CG aft on a canard is going to have the same effect as if it where a conventional plane, that being the elevator will be come "touchy", but you have to move the Cgh a long way back to get there. Also remember the elevator doesn't have propwash going over it to help out in slow speed flight so the plane just has to be flying faster than you may be used to.

Hope you get it repaired to fly again.

wilco3

Thanks, I did balance it with an empty tank so that would have made the c of g too far aft. I fixed the original damage and tried again today. Very fast across the ground and directly into the wind such as there was. Nothing, didn't want to lift at all, it just sort of bounced and cart wheeled and on the last effort and smashed the canard (again). Still no too much damage so I'll have another go, but balance with a full tank this time. Any other suggestions welcome.

bobzilla

My Feedback: (63)

canard elevators works backwards from normal tail elevator? check that.

wilco3

Thanks bobzilla, I got that sorted. But I am wondering if I've got enough throw on it (about 8mm). I'm a bit scared to increase the throw in case I make it more likely to stall .

bobzilla

My Feedback: (63)

I had the Nitro Long EZ..I put about 1/4" throw up and down..(my linkage was somewhat sloppy), plane took a long long run, i pulled
up elevator and plane dove up like a v2 rocket.. i pushed down somewhat and it dove down like a meteor..needless to say it was a
20 sec flight that ended in a pile of balsa..That was first and will be the last LongEZ I ever fly! Good luck on yours.!