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Ordered new batteries . . . we'll see . . .

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Old 10-15-2012, 09:16 AM
  #51
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Default RE: Ordered new batteries . . . we'll see . . .


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ORIGINAL: dolstinske


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ORIGINAL: serious power

Jason,
You are missing a point.
The extra capacity also gives extra performance, relatively speaking, as the flight progresses - less % capacity used = less voltage drop !!
There is no trade off.
I suggest you think it through a little more.

Brian
There is another aspect here which you may want to consider consider, as I have discovered. A smaller battery means less overerall weigfht, which means less power consumed. Here is what I find:

I have a very light Angel's Shadow, with a 5000 mAH pack, weighs 4800g. With a 4000mAh pack it weighs 4600g. One masters seguence with the 5000 mAh pack consumes 3500 mA, but the same sequence with the 4000 pack, consumes omly 3000 mA, so the % capacity used for each of these packs is nearly the same, the voltage at the end of the flight, is nearly the same.

I realize there could be other factors at play here, but I like the lighter pack and the way my plane performs with the reduced weight.

Your mileage may vary,

Dale

Hi Dale,
With all due respect I have to say something in your data does not add up.
Your data says that a 4.16% weight saving gives you a 14.28% drop in power consumption.
Sticking with that data set and extrapolate some ; by reducing the weight by 1400g you will need no power consumption at all to fly the same flight ???.
Also there is power used for more than carrying around some weight when flying - drag etc.

You may be flying a little neater with the smaller pack - just due to knowing that that is what you have on-board.
I know I do so with the smaller packs.

Brian
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Old 10-15-2012, 02:56 PM
  #52
rm
 
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Default RE: Ordered new batteries . . . we'll see . . .


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ORIGINAL: Silent-AV8R


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ORIGINAL: cmoulder

If the cost can be amortized down to $1USD per flight I am happy. Everything after that is gravy.

Consider that if a gallon of nitro is $25/gallon, give or take.
That's about 19.5 cents an ounce.
16 ounces of fuel will cost you about $3.12.
To use only $1 per flight in nitro you could only use about 5 ounces.

Kind of an interesting comparison.
You can skew the #'s to any view point you want. For instance.

I'm paying $19 gal for 25% cool power.

20oz gives me about 14 minutes of actual motor running.

If I compare it to the 8 minute flight I get with my electric.

That comes to about $1.70/flight. It will always be $1.70/flight.

Now if I eject my flight pak on the 28th flight into the corn field lost forever, that comes to $10.93/flight



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Old 10-15-2012, 05:38 PM
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Default RE: Ordered new batteries . . . we'll see . . .

Sorry, I was not trying complicate matters with the what-ifs nor to drag out the tiresome electric-vs-glow argument yet again.

Simply put, if I get 80 flights out of a set of packs that cost $80 then I am satisfied. So far I have gotten a lot more flights than that out of most of my 'cheap' packs. Every now and then there is a set that has inexplcable longevity, such as one my original sets of Zippy 20C's that has maybe 150 cycles on it. I don't know for sure how many cycles because I stopped counting after 80 or so.

I have 3 sets of Sky lipo 4400 40C's which are all approaching 60 cycles and the IR's are still fantastic and power is still excellent so these may be the best deal yet at $78 per set.
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