Batteries

[aramsdell]

I've been flying the Swift 16, actually 2 of them, for over a year now. Stock came with a 4S 3700 FP. I then got a 4S Maxamps. Sw 16 on 4S anything is just that though. I then went to 5S 4000 by Max Amps. I've been through a lot with these birds trying dif. pinion,batteries blades etc.
I've tried the 8T Century pinions and broken everyone.
I've got the 600+ motor and 9T with 550 Rotortechs.
I was flying a 6S Maxamps and a 5S. The 5S puffed a couple of times on 10 T. The 6S has puffed on 9T. I rebuilt both packs with the 4s used for spare cells.
First flight on rebuilt 6S resulted in extreme puffing and short flight time despite being fully charged(at least 4.19v each cell). My bird is just a performance pig.
I know I should probably reduce my collective but then it wouldn't outclimb a TREX 450 would it? Right now it's a rocket ship. It doesn't flip or roll as fast as a 450 but I just shake my head laughing everytime I get'er back down.
Whose running Lipos with 6S,600+,9T,550 RT' s or equiv. wide chord blades? What pack is giving the extreme performance I am asking for without ever puffing?
I have a Kongpower 5S5000 on my other Swift (helicam) but they are heavy.
Tired of experimenting with batteries and want a good one.

[RAV50]

I found the Maxamp cells to be questionable at best. IMHO, they highly overate there cells. The 4S packs I tested were 4S/4000/15C's and they delivered only 13.7V under load, and could only deliver about 2300 mah before I would have too land !!! POS in my opinion.

Then a friend gave me an Electri-Fly (he got it from Tower) that he was using in one of his planes, WOW, what a difference. Then I tried some Flight Power 4S/3700/20C and again, much improvement over the MAxAmps. The last four cell packs I tried were the latest 4S/3300/20C units from Century (only $110.00), again, they kicked the Sh%& out of the Max Amps, delivering very noticeable higher head speeds and flights that were more then twice as long!!

But if you really want all out performance, with the 600+ motor, go 9T or 10T and use good TP6S/5000/25C Extreme packs - WOW!!!

After all this, I cannot say enough about how important the use of real good battery packs, of true 20C plus ratings, are for top performance in driving our bigger heli rotors.

Try them, you too will see a big difference. When I first started with my Swift, I was told this, but thought I could save money by going Max Amps and with some other cheapies. Now they serve only as expensive paper weights!

[aramsdell]

Rav50, The cells I tore apart all were marked as 4200. I doubt they were capable of that after running at 20C more than a couple times. I don't have a data logger so I don't know what kind of current I'm pulling in a ballistic climb but it eats M.A.'s packs for sure.

[RAV50]

I have found that the "C" rating of a battery (if the seller is being honest about rating his batteries) is more important then the mah rating, when it comes to drawing anywhere from 500 to 1200 watts from a pack (That is what we will draw in helis using 520 to 560mm blades at rotor speeds from 1600 to 2100).

So it is important to use batteries that can provide these high power levels for the 6 plus minutes of the flight, not for just 1/100 of a second.

[Greybird]

I have read of problems like yours with 550 blades. Have you tried 515's? I have no experience with either, just what I have read.

[aramsdell]

I have 515's also but their is no comparison.

[RAV50]

It takes a lot more power to turn 550 blades compared to 515's. Turning 550 using a 14.8V 4Cell pack at a 1600 rotor speed for example, will work it very hard.

A good rule of thumb I use is that every 1% increase in length will require at least a 2.5% increase in power requirement. That of course is assuming both blades use the same airfoil and present the same type of drag coefficient.

So for example 550mm - 515 mm = 35mm
35/515 x 100 = 6.8% x 2.5 = 17.25 % more power requirement to turn at the same rotor speed.