Mounting twin 2800`s - Good or Bad?

[rotorhead42]

I recently ordered a few 2800`s Zippys, I noticed they`re heavy and I haven`t yet got the cable delivered to mount two of those in the phantom "external" cargo trays. I just want to know if anyone has done a test with twin 2800`s and what the results were. I got a gimbal, FPV, GPH3 with standard motors and props. Getting right now about 6-7 mins flight time before it turns ugly red.

 

[OI Photography]

I've got two 3000mAh Zippys that I fly with on the common under-arm dual batt trays. When carrying nothing but those and GoPro 3 (in waterproof case) I can get ~12 min with conservative flying and no wind to fight.

 

[martcerv]

If your using stock 8 inch props adding a second battery especially one that weighs around 230g is going to make it fly like $#it and only give you a couple more minutes fly time. You really want to be using 9 inch props and I am finding 9 inch triblades do quite well along with my upgraded tiger motors to a point. I havent bothered with dual batteries finding each 100g is worth about 1 minute in fly time, but using storm 2700's or Zippy 2800's I get just over 8 minutes with everything including the kitchen sink on my phantom. Max weight I have flown is just over 1400g which included another 450mah battery just for the gimbal. Flying at 1350g without that battery gets pretty much the same flight time but I think it flys a little better without that little extra weight.

Here is a test flight with the full setup in light winds 15-30kmh.

[youtube]http://www.youtube.com/watch?v=48V1JgcdL90[/youtube]

Here is my flight time before the gimbal and OSD which have added about 200g without the extra battery and so cost me about 2 minutes with similar flying.

[youtube]http://www.youtube.com/watch?v=ShtVGPx09KA[/youtube]

Adding a second battery will likely only add 3-4 minutes flying and I really wouldn't want to be flying a phantom that heavy which would put my setup around 1580g if I used 2 zippy batteries and I think even 9 inch triblades are going to struggle to lift that much weight and give decent flying performance.