nose dive first test - zagi
#1
Senior Member
Thread Starter
Join Date: Feb 2007
Location: glasgow, , UNITED KINGDOM
Posts: 3,349
Likes: 0
Received 0 Likes
on
0 Posts
nose dive first test - zagi
Hiya! First test flight of 480 powered Zagi resulted in nose dives - engine off or on. CG as per manual, weight 1lb+ as per manual. Plenty of up elevator (V-mixer), plenty of power but nose-dived big time. Room to move battery back 2-3 inches and to adjust angle of motor shaft up/down. Tried pizza box toss and overhead method launch but no go (only nose down). HELP!
#2
Senior Member
Join Date: Aug 2002
Location: Williston, VT,
Posts: 218
Likes: 0
Received 0 Likes
on
0 Posts
RE: nose dive first test - zagi
There are few things to check. Of course the CG is very important. This should be according to the plans. The elevons should be set at the correct angle. When viewed from the side the elevons should be approx 15 degrees above neutral. This should give you enough reflex to fly straight and level. The motor trust line should be inline with the flight path. Basically parrallel with a line drawn chordwise and - measured from the middle of the nose through to the middle of the trailing edge.
My guess is that you have not enough up elevator trimmed into the Zagi. Does that sound like a possibility to you?
My guess is that you have not enough up elevator trimmed into the Zagi. Does that sound like a possibility to you?
#3
Senior Member
Thread Starter
Join Date: Feb 2007
Location: glasgow, , UNITED KINGDOM
Posts: 3,349
Likes: 0
Received 0 Likes
on
0 Posts
RE: nose dive first test - zagi
YES! There was no upward trim with "hands off" - have now reset and will try again Friday - here's hoping!!
#4
Senior Member
Join Date: Aug 2002
Location: Williston, VT,
Posts: 218
Likes: 0
Received 0 Likes
on
0 Posts
RE: nose dive first test - zagi
OK! Flying wings need to have reflex in order to fly level. The trailing edge acts as the "tail" for dynamic balance. So, you need some up elevon for the wing to fly properly. I am sure you wilkl now be able to get this right.
#5
Senior Member
Thread Starter
Join Date: Feb 2007
Location: glasgow, , UNITED KINGDOM
Posts: 3,349
Likes: 0
Received 0 Likes
on
0 Posts
RE: nose dive first test - zagi
Hiya! I originally set elevon up as per instructions but it reset itself to neutral. Will try it Monday. Removed some foam to move battery forward 2in and the CoG is spot on (8in. from tip of nose). Feeling confident now. Thanks a milllon.