E-gurus: theoretical power question

[Frank v B]

If I need to produce about 600 watts for a plane (yes, 600!), what is the difference between producing those 600 watts with a Power 32 and a Power 60 using the same number of cells (4?)? 
In case you are wondering why, this plane needs nose weight.  A Power 32 weighs 7 oz, a Power 60 weighs 13 oz. plus, more importantly, I have a Power 60.  There is lots of prop clearance.
- Is it less efficient?
- Is it stupid?*


Frank


* Andy, the idea, not the writer!

[wollins]

Don't consider myself an expert but I've been known to run some "stinking power" through some planes so I just ran some numbers through Ecalc for you, Frank. There's a huge difference in prop for what you're thinking about doing.

11X6 APC (or equivalent) for the Power 32 and 16X12 APC (or equivalent) for the Power 60 should give about 40A/600 watts. Efficiency in this context is dependent on so many factors not the least of which is the size and type of plane so since you know that info, hopefully this should give you a starting point to extrapolate from.

My 2 cents.

Colin

[Frank v B]

Colin,


Thanks for the two cents...which is of course infinitely more than the knowledge (or money) I have on this issue.  A 16" prop for the .60!  That's bigger than the wingspan on some of my models.


A great starting point.


Frank

[Papa]

16 x 12. That's not a prop its a rotor with a slight warp!


Jack.

[Frank v B]

Jack,


re your: "with a slight warp!"


That describes the writer, not the rotor.


Frank

[wollins]

Colin,


Thanks for the two cents...which is of course infinitely more than the knowledge (or money) I have on this issue.  A 16" prop for the .60!  That's bigger than the wingspan on some of my models.


A great starting point.


Frank

Yeah that motor is much too low of a KV to get a reasonable prop size for the size of plane that you have in mind with 4 cells .  You could go up a cell (5S) and that'll drop the prop to 15x8.  (or equivalent) Amp draw drops to between 30 and 35A which makes things more efficient.

Colin