I have a large job coming up requires 24hrs flight in 1 day. Will be using 3 pilots. I have 10 batteries already but I'll need to hire more. Is there a formula or calculator that anyone has made that can calculate how many batteries I'll need taking into account charge time and reusing batteries.
Big job Batteries (calculator/app)
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Lot of ways to look at this one. Hopefully, someone with similar experience to yours will answer. My comments are on a "per drone" basis. I would just use 25 minutes of flight time and 75 minutes to charge as a basis. If you had three chargers then three batteries should keep you flying full time. In the real world you might want to be more conservative.... 20 minutes fly/90 minutes charge etc. I tend to favor buying more new chargers than batteries. Hope this helps.
Hopefully this goes well for you. Very interested in the results.
Please post how it was accomplished when the job is done.
My only advice would be - too much heat is not your friend with electronics.
I'd consider - battery cool off period / after flight / after charging
Then it's up to how well DJI designed & tested the P4(P?) for repetitive flights.
Is the drone going to be stationary for 25 minutes or moving?
Are the battery connection terminals / PCB's / ESC's up to the challenge?
I'd assume there's a duty cycle but have never seen one published.
I can only assume your landing, replacing battery and launching right away.
Best of luck on this. Let us know how it goes!
Please post how it was accomplished when the job is done.
My only advice would be - too much heat is not your friend with electronics.
I'd consider - battery cool off period / after flight / after charging
Then it's up to how well DJI designed & tested the P4(P?) for repetitive flights.
Is the drone going to be stationary for 25 minutes or moving?
Are the battery connection terminals / PCB's / ESC's up to the challenge?
I'd assume there's a duty cycle but have never seen one published.
I can only assume your landing, replacing battery and launching right away.
Best of luck on this. Let us know how it goes!
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At least two drones if you want to have the drone full-time in the air. Cooling is an important factor as my predecessor said!
You can not calculate 25 min of flight per battery. Usually, a safety factor is 30% at the time of landing (70% of 25min = 17,5min). And this is for relatively new batt.
Then an essential item in this calculation is recharging cooled batteries (YES or NO) during the event. Then the number of batteries charging at the same time (at least 3).
It can be done with 10 batteries and maybe even with 9, but I would go with 12 just to be sure.
If charging is not possible during the event then you need at least 5 batteries per hour. And an additional one for the second drone if the event must be monitored continuously.
A lot of parameters as you see so the result is on you only.
You can not calculate 25 min of flight per battery. Usually, a safety factor is 30% at the time of landing (70% of 25min = 17,5min). And this is for relatively new batt.
Then an essential item in this calculation is recharging cooled batteries (YES or NO) during the event. Then the number of batteries charging at the same time (at least 3).
It can be done with 10 batteries and maybe even with 9, but I would go with 12 just to be sure.
If charging is not possible during the event then you need at least 5 batteries per hour. And an additional one for the second drone if the event must be monitored continuously.
A lot of parameters as you see so the result is on you only.
Is this 1 drone on station being shared by 3 pilots, or 3 drones continuously in the air for 24 hours.
Hopefully, you need 1 drone in the air, and have 3 drones available, both for backup reasons and to have continuous coverage.
Are you shooting video? Wow, talk about need for huge file storage.
24 hours, wow, talk about changing light conditions.
My answer is the more batteries, chargers, and microSD cards, the better. Maybe some cooling fans before and after each battery charge before reusing. Or maybe it's not a good idea to "rapid cool" batteries?
We all want to know how this crazy deal turns out.
btw, I seem to recall someone selling a tethering system for Phantom that actually tethers a huge battery pack on the ground for continuous flying. Ridiculously expensive for average pilot, but maybe justified for this gig?
Hopefully, you need 1 drone in the air, and have 3 drones available, both for backup reasons and to have continuous coverage.
Are you shooting video? Wow, talk about need for huge file storage.
24 hours, wow, talk about changing light conditions.
My answer is the more batteries, chargers, and microSD cards, the better. Maybe some cooling fans before and after each battery charge before reusing. Or maybe it's not a good idea to "rapid cool" batteries?
We all want to know how this crazy deal turns out.
btw, I seem to recall someone selling a tethering system for Phantom that actually tethers a huge battery pack on the ground for continuous flying. Ridiculously expensive for average pilot, but maybe justified for this gig?
Meta4
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It's not possible to charge the batteries until their temp drops to a suitable level.
There's no worry about the drone in repetitive use.
Meta4
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It's not possible to charge the batteries until their temp drops to a suitable level.
There's no worry about the drone in repetitive use.
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What your saying could very well be true!
For safety and longevity, I personally error on the side of caution with my equipment.
Heat and electronics don't go well together.
Maybe 24 hours of repetitive flying is no big deal. Maybe 48 hours. Maybe more!
Can only assume DJI has some data on this.
I've never seen or read and data on it and certainly wouldn't experiment with my P4P because someone "says" it's no a big deal.
The highest summertime temp AirData recorded on one of my batteries was 155 deg. I'm sure others have seen higher temp's.
Now pair that with a battery just off charge after DJI's logic says was cool enough to charge.
What might it have peaked at if I were doing repetitive flights that day. What would the internal temp of the PCB's/ESC's/etc in the drone?
All worst case and all unknowns.
Depending on the situation, the paycheck might help outway the risks..
Curious how this turns out.
I did it myself and made a spread sheet. That can be used for any drone if you know average flight time. Made it so I could work out number of batteries needed, chargers used and flyers. I worked it out at 20min per flight. Can adjust though.
I cannot give specifics. But a major international even that wants a reality model of a 300ha space and I'm given one day to do it and make it work
The total capture time is 24hrs over 3 drones and pilots we have 11.5 hrs of daylight and 3 pilots to do it. I'm estimating 27hrs over the 3 pilots. So 9 hrs each. Total flying time. The paycheck outweighs the risk by a long way. It will not be hot. The time of year is usually mild or bad. 6 hrs flying isn't something we don't do on occasions. I'm just trying to coordinate 3 pilots with 3 drones and work out the logistics
Meta4
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It is ... that's why I said it.
I've run 7 batteries back-to-back through mine on a number of occasions.
And a few years back DJI did a demonstration with a tethered drone running for 72 hours straight.
The drone has a cooling fan that's running while it's flying and gets a lot of additional air cooling from the air and the 4 props.
It's a reality model so teather is out of the equation. The 24hrs is 24hrs total capture time required so about 27 hrs flight time. We have 11.5 hrs of daylight to capture that with 3 pilots. So big job. We will be running 128gb sd cards in each so no problems. 30 batteries and 8 chargers. Not a video it is 45deg grids of 300ha
We have to capture 300ha in 24hrs so tethered is off the cards but a cooling fan might be an added feature. Any details?
Meta4
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Obviously tethering is not an option for a mapping mission.
I only mentioned that DJI ran a tethered test for 72 hours straight for someone who felt it would be unwise to fly batteries back-to-back.
Your Phantoms already have cooling fans built-in.
HI.
For maping purposes, above 100m height, an aprox of lineal 10km per battery .
Depends from App you use, light conditions, flying speed and height, but is an real estimation based in many previous jobs.
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I get involved with search and rescue, media coverage, and UAV flight training where we need to keep a Mavic or Mavics in the air nearly full time for hours at a time landing only to charge the batteries.
For the Mavics, we use AC-powered “Yx for Mavic” smart chargers that are able to charge three batteries at once on separate circuits. We also use USB-powered fans (powered by the Yx) to cool the batteries when needed.
Typically, we need to rotate between 6 to 8 batteries per drone (depending on ambient air temp and wind conditions) to keep the drones flying.
Sometimes events dictate when to swap batteries rather that battery voltage. This is especially true for media coverage.
I would be surprised if Yx or others don’t make a similar charger for the Phantom.
For the Mavics, we use AC-powered “Yx for Mavic” smart chargers that are able to charge three batteries at once on separate circuits. We also use USB-powered fans (powered by the Yx) to cool the batteries when needed.
Typically, we need to rotate between 6 to 8 batteries per drone (depending on ambient air temp and wind conditions) to keep the drones flying.
Sometimes events dictate when to swap batteries rather that battery voltage. This is especially true for media coverage.
I would be surprised if Yx or others don’t make a similar charger for the Phantom.
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Four batteries is all you need to keep each drone in the air with back to back flights as long as you can keep the chargers running. If it is hot, maybe 5 batteries per drone or forced cooling of some sort for the batteries.
I never have had any issues with the drone overheating even in hot weather. I routinely fly a 2000AC site every week for the past 6 months.
I never have had any issues with the drone overheating even in hot weather. I routinely fly a 2000AC site every week for the past 6 months.
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