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nose dive first test - zagi

Old 03-07-2007, 08:17 AM
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tam popo
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Default 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!
Old 03-07-2007, 02:38 PM
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salnsp
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Default 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?
Old 03-07-2007, 04:16 PM
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tam popo
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Default 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!!
Old 03-10-2007, 11:07 AM
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Default 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.
Old 03-10-2007, 02:54 PM
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tam popo
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Default 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.
Old 03-12-2007, 06:09 PM
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Default RE: nose dive first test - zagi

Good luck! Let us know how it works out.

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