Hi,
  I have a question about the potenital to overheat the phantom 4. I have a 3 hour event and am looking to be in the sky for a large portion of it. Is there any test in regards to how long you can fly the phantom 4 before the camera or or motors need to cool down? I am going to have 6 to 10 batteries to use so I can potentially be in the air for the entire event. I am wondering if i should have two phantom 4's and rotate them during the event to let the other cool down. Thanks for any insight.

Regards,
Mike Mason

Good question Mike,
Your single most important issue would be motor temperature (after battery of course)

Both the battery and the motors are subject to overheating under certain circumstances.
But since the battery requires charging after use, the assumption is that the battery will not get too hot from use....that leaves the motors.

With one Phantom, the best thing to do is to plan on approximately 10 minutes for the motors to cool down after every 15 - 20 minutes of flight.
While you "could" fly immediately after changing  batteries, the motors could reach a temperature where the insulation on the wire strands inside the motor begins to get hot enough to begin breaking down.
The cooling motor in the VPS also gets hot.

You could purchase a laser thermometer and check the motors temps after flights.  Anything above 150F - 160F and I would let them cool down 10 minutes.
Damage to the windings in these small motors can start at around 180F.   Larger motors can take much more heat.   Insulation class is a factor.
Also, as the motor temps rise, internal resistance in the motors windings rises at the same time.   That causes the motors to draw more current, and making the heat problem worse.

Having two and letting one cool down while the other is in flight is a most excellent strategy

The question is good and my answer is just what Cessna said.
I've filmed with 3 batteries in a row nonstop (just for changing the batteries) which was almost an hour of flight and didn't have a problem. However I had a couple of times overheated motors when flying with strong winds, and this just happened 10-12 minutes after starting fresh with one battery.

Thanks guys! Exactly what i was looking for.  I think i will use the 2 Phantom 4 strategy to be safe.

I'd be worried about the tablet or phone you'd be using.  I doubt any tablet or phone would be able to last 3 hours without overheating and/or needing a charge.

Do you have two of those?

timmer1 Posted at 2016-7-14 16:36
I'd be worried about the tablet or phone you'd be using.  I doubt any tablet or phone would be able  ...

good point
although the remote trickle charges the phone / tablet. My Galaxy Tab S2 lasts 3h easy. cheaper android tablets may not..

Thanks that a good point. I will be on a boat so i will need to make sure to bring my portable USB charges for my ipads.

I agree with Cessna and if the drone reaches its threshold, the app will prompt up a warning notice at that time. What's more, the power bank is necessary when you are working on a long-time mission.

If you are concerned about the phone or tablet getting too hot, your best choice would be an iPad Air 2, they have lots of case area to dissipate the heat, and I have used mine in very hot conditions and it stayed well below a critical tewmperature.

4Kpromos Posted at 2016-7-15 03:24
Thanks that a good point. I will be on a boat so i will need to make sure to bring my portable USB c ...

Also, you can fly them in turns, after every battery. Since you don't want to keep one flying until overheating and the drone lands into water.

I had the same concern.

I phoned up DJI and this is what they told me:
- monitor the outside temperature - the P4 batteries can be operational between -10 to 50 degrees celcius.
- monitor the inside battery temperature - it can go up to 60 degrees celcius. At a certain point there will be warnings on your device stating to land the aircraft if over heated.
- according to DJI, between one battery and another, the aircraft should take a break of about 10 minutes - due to the heating inside it

My recommendation:
- request a room with Air Condition and while replacing an empty battery with a fully charged one, place the phantom in front of the AC unit.
- monitor constantly the battery temperature as well as the rotors
- take precautions always, use your own judgement

Enjoy your fly!

Seems you got good advice, again it would matter on how hard the motors are working. Are you trying to hover in one place and fighting the wind? That would cause more heat then no wind or flying around in mellow forward flight.

I have flown mine in 90 degree weather, no clouds, in the middle of the day for about 30 minutes using 2 batteries with no issues.

I wonder though, is there an overheating warning for the rotors?  or just the internal battery temperature?  

I always do a course check using my finger after each flight, manly looking for relative temperature variation, (not obsolute),  between the 4 rotors.

In my experience, the P4 gets hotter when hovering, or just playing aroung at low altitudes.
I just checked my logs and the max battery temp was 135 degrees F (57 C); starting from 90 F; flight time was 19 min.

Thanks guys for all the advice! I take flight on Saturday! I will let you know how it goes.

4Kpromos Posted at 2016-8-4 10:19
Thanks guys for all the advice! I take flight on Saturday! I will let you know how it goes.

We recently shot a wheat harvest in 90 degree weather and flew 8 batteries down to 28-30% one after another in our P4.  Highest battery temp noted in the logs was 140º.  Didn't have an infrared thermometer but checked motor temp by hand and it seemed relatively the same each battery change, though could have been increasing incrementally.

Did pretty much the same thing a couple of weeks before, though the weather was in the upper 70's, low 80's for most of the flying.

Did have a case of the IPad Pro over heating later in the day when the temps got into the mid 90's.  Picture started breaking up badly, so landed and quite flying for the day.  Have been very concientious to keep it cool since then.  Part of the problem I think was we had the keyboard case on the IPad so that dramatically reduced it's ability to cool.

Will definitely carry an infrared thermometer from now on.

Thanks for the original question and good answers.

I've flown several times in 80+ degree heat, five batteries in a row without pausing to cool.  Never thought about the heat being a problem.  I guess I got lucky?  

Hi, I have a new mavic drone (similar motor design to the phantom in this thread). I find that one of the four motors gets very hot (enough to burn you).

After 15-20 mins flying in 35C/95F heat three motors are warm/quite hot to touch (i'd guess around 40-50 degrees). The final motor (rear left) is much, much hotter - I'd guess around 80-100C. It will burn you if you touch it by accident.

I'm concerned about melting the housing or damaging the motor and crashing the drone.

Does the drone monitor motor temp? If the motor did fail could you land the drone?

Many thanks,Will

will.rs Posted at 2017-2-18 08:13
Hi, I have a new mavic drone (similar motor design to the phantom in this thread). I find that one of the four motors gets very hot (enough to burn you).

After 15-20 mins flying in 35C/95F heat three motors are warm/quite hot to touch (i'd guess around 40-50 degrees). The final motor (rear left) is much, much hotter - I'd guess around 80-100C. It will burn you if you touch it by accident.

If it's a genuine concern that it could melt or damage the surrounding plastic then I would take it back to the dealer for a replacement. If one motor fails then gravity will take over and the Mavic will drop to the ground, probably in quite a spectacular fashion.

It could just be that the one motor had to work a bit harder during the flight, but I would expect them all to be more or less the same temperature. Do you know anybody with a laser thermometer, that would be more accurate ? Is the same motor always hotter than the others ?