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Old Jan 14, 2013, 08:14 PM
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Willoughby, Ohio
Joined Jan 2002
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Thrust tubes do not gain static thrust they increase dynamic thrust in flight and your test results prove just that. To achieve the same thrust with a smaller outlet nozzle (thrust tube installed) means the velocity of the air coming out is much faster than without the thrust tube installed. This means the top speed of the model will be higher with the thrust tube than without it installed. That is the purpose of a thrust tube, to gain top end speed not to maintain low end thrust. Also they are generally installed when there is excess power to be harnessed. The stock power system on this plane is really only enough to make it fly around. So a thrust tube may not increase the top end speed really as it needs almost all the thrust it makes just to fly at a normal speed. If you put in a high power system like I did then you have extra power to play with so the increased efflux speed makes the model fly faster, typically 8-10 mph is gained over not having one. So for the stock motor on 3S I would agree to not install the thrust tube, but only because the stock watts are too low, not because the trust tube concept does not work. I just want to make that distinction.
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Last edited by The Don; Jan 14, 2013 at 08:34 PM.
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