This sudden drop issue occurs when you fly a battery that has self discharged. It's a firmware bug.  Do not fly any battery that has entered self discharge mode without fully charging it first.  If you do fly it without charging it first it will more than likely keep having the sudden drop behavior until you drain it till it powers itself off and fully recharge it to reset it. Same as user manual recommends to do every 10 charge cycles.  Never fly a battery that self discharged without fully charging first and set self discharge time to 10 days, it's set at 2 by default which is why this problem occurs so often.

Thank You. This problem had not been elucidated back in May, when the phenomenon was first reported.

To be Consistent and get as many valid data sets as possible it would be worth while for everyone concerned with monitoring multiple battery packs performance if you Register on " Healthdrones.com " and upload all your flight logs there...
The data extracted from the logs give a very good measure of flight performance - GPS, Controller Signal, and battery power problems...

purchased a new inspire 1 V2 last week, was out and fly yesterday and my battery dropped from 27 to 7%... good that i was in the area.. What do you guys think is the problem?

The real issue here is the logic board is shit at actually reading the cell volt count. What it reports and the real cell voltage count is not the same. That explains the sudden drops from 30-7%. It will also report damaged cell if one of them is not balanced. Either High or low voltage of .2 or .3 will trigger it.

---DO ONLY IF YOU KNOW WHAT YOU ARE DOING---
Simple test if know what you are doing is to open the shell and use a multi metter and record the voltage of each cell from its balance lead. Put it back together then look at the APP. They are not the same readings. Yes I know a slight load has been added but they will report off.

axel_j2s@yahoo. Posted at 2016-6-8 16:10
purchased a new inspire 1 V2 last week, was out and fly yesterday and my battery dropped from 27 to  ...

Try discharging the battery down below 4% and the recharging. Also, did you take off with a full battery or was it already partially discharged?