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Title: Motor and prop. Position Post by: sandeepm on June 19, 2009, 01:15:23 PM I would like to know one simple thing.............
in pusher conf. motor and prop is mounted in reverse order then standard mounting see below: (http://img36.picoodle.com/img/img36/2/6/19/sandeepm/f_motorpositim_30bdd1c.jpg) (http://www.picoodle.com/) My Question : can the motor and prop. be mounted in standard way in pusher jets designs? Sandeep Title: Re: Motor and prop. Position Post by: santhosh on June 19, 2009, 01:36:14 PM yes u can mount the motor and the prop in the standard way
Title: Re: Motor and prop. Position Post by: RotorZone on June 19, 2009, 02:10:59 PM In pusher configurations the heavy motor at the back makes it difficult to achieve proper CG. You'll need to move the battery way forward and still need to add weight in some cases. Having the motor closer to CG reduces this issue.
Title: Re: Motor and prop. Position Post by: rcforall on June 19, 2009, 02:20:36 PM As Rajesh says Simple Principal of levers , as the distance of the load from the fulcrum ( CG ) increases a greater effort is required to counter the effect of that load .
JUST IMAGINE THE PLANE TO BE A 1ST ORDER LEVER WITH THE CG AS THE FULCRUM AND WITHOUT THE THRUST OF THE MOTOR THE ANSWER IS THEN EASY TO COMPREHEND . This is one of the main reasons for Heavier planes having their servos around the CG or at least close to it . Sai Title: Re: Motor and prop. Position Post by: izmile on June 19, 2009, 05:10:22 PM Yes, you can mount the motor in the way you have shown. But the reasons Rotor said will perfectly apply. Further you need to run longer wires around the prop clearance to get to the battery. If its glow motor then you possibly have the fuel tank further behind the motor - compounding the CG balancing issue.
Title: Re: Motor and prop. Position Post by: Pikle6 on June 19, 2009, 05:14:40 PM that is just what i did in f22 w/thrust vectoring the battery was placed in the cockpit area and there ran an extension battery wire to make it reach up to the cockpit. for prop mounting if you do not have a pusher prop but do have a pusher motor just flip the prop and insert your prop there you have it a pusher prop
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