Jason Merkle
Senior Heliman
Location: Champaign, IL
| Ive been lucky enough to spend a lot of time with Mr Charlie Wang (CEO of Thunder Power here in Las Vegas) discussing the Thunder Power product line. I once asked same the same question about 5p, 6p+ packs. Charlie gave me excellent insight to why such packs do not exist in the production line...
Most importantly, the idea of the larger 7800-8200 mah packs was to replace out current sub C packs - increasing capacity while still reducing weight and keeping the same level of power as the packs they replaced. Overall, the end result was just what many of us who have flown electrics for some time now were looking for... 20-30% less weight, with 3-4 times more flight time and the power we were always used to!
While 5p+ packs would indeed further increase flight times, such packs would be very close in weight to the sub C cells and packs we're so anxious to replace. For some, they may want all the flight time they can get even at the same weight as the previous Ni technology, but for most, this simply isnt what we're after.
Overall, 15-20 minute flight times are what most people would like to see - with as much power as possible. Based on the motor combos many run now, a 6000-8000 mah battery would be just about right to achieve this level of perfomance.
One benefit to more capacity in our packs would mean that we would get better voltage under load. The higher the capacity, the less the voltage within the pack would sag during flight - such as in agressive 3D type flying. BUT, the added weight would reduce the overall performance. 3D flying is a balance of power and weight which is why many top pilots who fly 60-90 powered helis will use smaller 30 sized landing gear, no header tanks and lightweight Rx packs.
It is still possible to build your own 6p packs using the currently available 3p Thunder Power packs. For a heli like the Bionic though, a 12,000 mah pack is more than you would ever need. Yes, flight times would be 50% longer than with the current 4p 8000 mah packs, but do you really need more? Typical 3D flight times on the Bionic heli with the Hacker C50-19XL or Pletti motors on 8-10s4p packs is 15-23 minutes. With 2 sets of the 4p packs you could fly for 30-45 minutes per session with recharging. While a 6p pack might fly for 25-35 minutes, most would prefer 2 slightly shorter flights because they overall performance on the lighter packs would be much better.
If the 4p packs could not handle the 3D flight loads the Bionic could deliver I might suggest going with larger packs. But even helis like the Joker which are known to pull up to 70 amps for short term bursts fly better on the 4p packs than they did on the old Ni technology.
Something else to think about is the shape of the pack. A 5 or 6p pack would be very thick making difficult to fit into many helis and airplanes where the 4p packs readily fit now. Having also seen the production process first hand, building 5p+ packs would be much more difficult, further adding to the complexity and cost of the packs.
I think Charlie has done an excellent job in delivering the very best balance of size, fit, performance, capacity and price. If you havent already flown some of the 4p packs, Id suggest giving them a try before looking into higher capacity packs. All my electric helis fly solid 15-25 minute 3D flights using the 8000 mah packs - exactly what Ive been looking for since I flew my first electric helis and airplanes 7 years ago  Ive sold ALL my Ni packs and strictly fly Thunder Power batteries in all my airplanes and helis - all the way from the small 2s 730 mah packs to 8s4p 8000s in my larger helis!
Jason |
