Lipo cell capacity

[woz]

I am totally baffled by this whole lipo Voltage/ Mah relationship!
All you electric boffins - help please !
I am sporting a new charger that allows you to see the Mah that is put back into the packs when charging.
Now I run 2x 2250mah 11.1v packs in series to power my 2kg heli(hurricane)
after flying for about 8 minutes , cells had discharged to a point where I could still lift off but with effort to climb! so I landed unplugged etc.
I then put them on the charger and voltage was 10.8 and so it started. I pumped 1890mah into the first pack and 2318Mah into the second pack. the voltage on 2nd pack was 10.7v .
Now what I don't understand is the difference in Mah per pack concidering it's in series and 2nd can a pack take more than it's rated?
I was nipping (as you would expect) but the cells didn't swell or overheat!
I have since flown the packs again and this time put in 2214Mah and 2050mah respectively. again no swelling etc.
can anybody tell me about this- besides that I may have overdischarged the packs!
I obviously ned to check the ESC programming soon! and fly less time !!

[Pinecone]

Did you charge and balance the packs in series? If not, you may have started out with the packs at different levels of charge.

You want to shoot for putting back in no more than 1800 mAH in eachpack. So if you are putting back in about 2100 mAH in 8 minutes, you are pulling about 2100/8= 262.5 mAH per minute. So to keep the pack usage down to 1800, you need to fly no more than 1800/262/5=6.85 minutes, or rounded down 6 minutes 45 seconds. I would set my timer for 6 minutes and let my packs live longer.

[woz]

Pinecone Thanks, I have just finished charging the packs again and timed about 7 mins.
You are spot on !! my calc is 263 mah/min based on previous charge and now again !
So 7minutes it is to 1800mah recharge.
I have the feeling the one pack was slightly discharged but I usually fly the same packs.
I have another 2 identical packs but use those for my 450! aybe some confusion !
Thanks again for the input!
I have just ordered 2 3300mah 22c packs so here's to longer flight time !