Actual Battery Usage of Phantom-2

[jvancraa]

I have a Phantom-2 (no Vision) with a GoPro Hero 3+, Zenmuse H3-3D, Boscam 32CH FPV-TX, Flytrex Core-2 and iOSD Mini. The total weight of the kit-in-air incl. battery is 1407 Grams.

I recorded a flight incl. On Screen Display details and made a graph of the battery usage over time, I'm getting 14-16 minutes flight time out of the DJI Intelligent Batteries when i am flying in circles horizontally above the ground with 2-3 bft wind (see picture).

Given that i have quite a hungry FPV Transmitter i did not expect the max. 25 minutes flight time, however I think a max. flight time of 14-16 minutes is a a bit of a dear penalty to pay for the FPV.

1) Do you think this battery usage is normal for a configuration such as mine?
2) How much flight time do you get out of your Phantom and (how) does your kit-configuration differ from mine?
3) Could you give me a recommendation on how to extend the flight time, w/o loosing functionality

 

[xgeek]

That looks about right. I get around 15/16 minutes until I hit 30%.

Your Phantom is a bit fat so you could try trimming some redundant weight off it. Do you have prop guards on?. Mine comes in at 1347g and I have a v1 Flytrex and a GPS tracker on mine.

 

[FASTFJR]

Thats about right, I around 15 minutes when I hit 30%. I have the 3 axis gimbal, go pro, AVL58 and iOSD. With nothing attached I can get 25 minutes

 

[jvancraa]

Indeed, albeit that i took some of the extra gadgets off that i added without thinking (which already saved 6% on weight), my Drone still is a bit fat today:

As you can see, I have 4 DJI prop-guards of 18,7 grams each on my Drone. If I take them off, my drone will weigh less than 1332 grams. Taking the prop guards off will probaly also make the drone more aerodynamic and suitcase-friendlier.

From your response i understand that removing the guards I wil give me a similar config to yours and my max flight time (up to 30% battery) will increase with 2-3 minutes per flight. This is definitely worth considering (even if it will cost me a couple of extra props), thanks for the tip.

Once i no longer use the prop-guards, I could switch to the larger Carbon Props as well. Could this impact battery life and/or speed as well or would you recommend me to stick to the plastic ones?

 

[xgeek]

I have never used CF props, so do not have any first hand experience. But everything I have read leads me to believe they are a waste of time. I am happy with the OEM props so have stayed with them.

The iOSD can be stripped down to save some weight. The case and CAN-Bus cable can save around 10 grams. Here is a photo of my iOSD:-

 

[ElGuano]

I have never used CF props, so do not have any first hand experience. But everything I have read leads me to believe they are a waste of time. I am happy with the OEM props so have stayed with them.

The iOSD can be stripped down to save some weight. The case and CAN-Bus cable can save around 10 grams. Here is a photo of my iOSD:-

+1, one of my favorite mods. iOSD goes from about 16g to 5g, cables included.

 

[jvancraa]

I took of the prop-guards (75 grams), replaced plastic props with the carbon fibre props. Flight time (from 98% to 30%) increased to 15 minutes (exactly the same as FASTFJR). Total Drone Weight incl. camera/gimbal/battery etc now is 1321 grams. I.e. 75 gram reduction brought 2 mins. extra flight time.

I could strip of another 270 gram if i make the drone completely bare. Mathematically this would increase flight time with 2 * 270/75 = approx 7 minutes (i.e. up to 22 minutes from 98% to 30%).

Only taking the IOSD apart and removing its casing (thus saving 11 grams) would give 10 secs extra flight time. For me, the risk of ruining the iOSD (i'm not so good with a soldering iron) does not way up to the possible gain of 10 sec extra flight time.

Question. Has anybody every tried to place two intelligent 5200 mAh batteries in parallel in a Phantom-2? Theoretically this would increase the total weight with 391 grammes (thus costing approx. 2-3 minutes of the flight time) but the extra power would increase flight time with approx 15 minutes, i.e. up to 30 minutes.

I also consider to lower the battery alarm levels to resp. 25% and 15% (i believe the drone comes down at !5% independent of the setting in the DJI Navigator). Lowering the first alarm from 30% to 25% would given me 5% (approx. 2-3 minutes) extra flight time, but would limit the Return to Home battery capacity to approx. 1200 mtrs (which distance may be considered as being out-off-sight, which is illegal in the Netherlands)

 

[WPSPETE]

From my 3 flights I get 14-15min. I come in right at 30%. I am happy with it. Instead of screwing around with trying to lighten it up I am just going to purchase two more batteries.

 

[jvancraa]

I agree 14-15 minutes is very decent. And yes, buying additional batteries does makes sense when you fly within line-of-sight. Rationalisation of weight also is good. I.e. by replacing/trimming components it is possible to reduce weight without loosing essential functionality.

E.g. this week i added a Futaba Receiver linked to a Power and a GPS sensor so that I can see, monitor and log the Telemetry data on the Futaba 14SG Controller. I could have left the DJI Stock Receiver in the drone (which would have been the simplest) but choose to remove it to minimize weight and to compensate for the weight of the extra sensors that i added.

 

[OI Photography]

Question. Has anybody every tried to place two intelligent 5200 mAh batteries in parallel in a Phantom-2? Theoretically this would increase the total weight with 391 grammes (thus costing approx. 2-3 minutes of the flight time) but the extra power would increase flight time with approx 15 minutes, i.e. up to 30 minutes.

Unfortunately, the math doesn't work out all nice and tidy like that

Every gram you add above ~1400g hurts your flight time more than each gram below that rough threshold. Adding the weight of a 2nd DJI 5200mAh batt would probably eat more like 5 minutes of flight time. And even if the weight didn't bring that added penalty you still probably can't get more than 1.5x-1.6x the original flight time with one battery (it doesn't just double when you add another in parallel).

That being said, I'm not sure if it's even possible to do a parallel config with DJI's smart batteries.

 

[jvancraa]

Indeed, reality thought me that I have reached the point where the drone needs to loose weight and I need to buy more batteries.

My conclusion: If I want Steady Video (ie. a Gimbal), FPV, iOSD, I need accept the 14-15 minutes flight-time per battery.

 

[hrosee]

How much do you guys think the way you fly effects the battery time? I tend to go up at full throttle and usually climb higher than I probably need to. Also the use of moving the gimbal up and down. Being a new quad flyer I tend to play with the gimbal up and down a lot.

I would like to hear from you guys that are getting longer flight times if you have adjust how you fly to get longer flight times. By changing altitude a lot at full throttle I am probably drawing a lot more current than if I took it easier going up.

 

[Fyod]

It would make sense that not going wide open would save some battery.
In my experience, most effect on battery is wind, since the motors keep fighting it to stay steady, but that's also because I fly in GPS mode most of the time.
I don't think gimbal tilt has significant effect on flight time.

 

[evilfurryone]

14-16 minutes here as well depending on wind. I am pretty happy with that. Have no plans to currently shave off any weight.

When I did some distance flying to 2 km and back it used 30% of the battery so I don't really have a reason right now to really extend that flighttime.

My solution was to get extra batteries. so ca 75 minutes of flight time if I don't have any chargers nearby is good enough for me at this time.