I have had my Q 500 drop out of the sky 3 times now and here is what I found

[Donald]

If you have used the return to home fun
ction and take off again with the switch left in return to home it will drop out of the sky. You must make sure the switch is put back in angle or smart before you fly again. Try it by leaving it on the ground . Start it up with low battery in smart mode, then switch to return home and the quad will stop.

 

[Steve Carr]

That is normal operation.
1. If you start the motors in Angle or Smart mode and then switch to RTH the motors will shut down because the Q is already at home.
2. If the switch is in RTH, the motors will not start.
3. If you are flying closer than 26' and you switch to RTH, the bird will fly away from you until it is outside the geo-fence range and then it will land.

 

[Donald]

That is normal operation.
1. If you start the motors in Angle or Smart mode and then switch to RTH the motors will shut down because the Q is already at home.
2. If the switch is in RTH, the motors will not start.
3. If you are flying closer than 26' and you switch to RTH, the bird will fly away from you until it is outside the geo-fence range and then it will land.

Thanks for the input Steve ,you are right . The only other thing I figure out is ,it has something to do with the batteries. I haven't used them for a while waiting for parts as it dropped out at 100 ft before and ruined the body and motherboard. I replaced it with a new one. Did all the updates and callibrations and again it dropped out of the sky twice. It was cold outside and the batteries drained very quickly ,within 3 minutes. I took them out and waited a minuite and put them back in and they show 3/4 charge. I tested it with the drone sitting on the ground ,fired it up and idled, batteries showed good ,it kept running ok in angle and smart and when I hit rth , it shutdown immediately. Earlier when it dropped the second time on me I noticed that the lights were still on which means it was still getting power to the mother boad,but not enough for the motors to run. I will do some more testing tomorrow and will post anything I find . There has to be a reason and they are too expensive to just keep dropping out of the sky.
Don

 

[Jan Verhagen]

That's what happened to mine too...... twice.
Only the first time it dropped into a pond, was there about 1 minute under the water, but when i got it out of the water, all the lights were flashing; don't remember their collors but only they were flashing.... I was sure i had a full battery ...... But did not know how i landed the time before that (was about one week earlier), could have been in angle or rth.....
There was no further damage and i started drying with a ladies hair föhn within two min. after the fall (about one min. in the water). Let it dry in the sun, also in the days after the fall kept it drying in the sun. Just one esc was damaged and i replaced it. After reprogramming the esc and testing with the guy i tested every thing on the ground. Every thing seemed to work oke. Oh, and nothing happened to the camera, worked perfect again......

The seccond time it fell out of the sky (about 2-3 mtrs) was the test flight after that. I remember it was on the seccond battery after i took it to land on the first battery by rth. Than put the seccond battery in and flew away; testing flying not to high. I was sure all of my batteries were full...... I was taking it home with the rth and than it dropped before it went to 10 mtrs.(just one leg broke down, camera oké and body oké). All the lights were flashing.......

My distance was far enough to not be troubled by the geo fence. Testing with the GUI again i could not find anything wrong. Also testing on the ground (no props), showed nothing..... Only the wheather was here to bad to go flying untill now.

So could it be possible that after using the rth and than flying again something in the command to the motors is going wrong by low battery ? Though i am sure mine were full. If the wheather here is going to be better i will try to set up some testing for my Q500...... and ofcourse i will report it here.

 

[Donald]

That's what happened to mine too...... twice.
Only the first time it dropped into a pond, was there about 1 minute under the water, but when i got it out of the water, all the lights were flashing; don't remember their collors but only they were flashing.... I was sure i had a full battery ...... But did not know how i landed the time before that (was about one week earlier), could have been in angle or rth.....
There was no further damage and i started drying with a ladies hair föhn within two min. after the fall (about one min. in the water). Let it dry in the sun, also in the days after the fall kept it drying in the sun. Just one esc was damaged and i replaced it. After reprogramming the esc and testing with the guy i tested every thing on the ground. Every thing seemed to work oke. Oh, and nothing happened to the camera, worked perfect again......

The seccond time it fell out of the sky (about 2-3 mtrs) was the test flight after that. I remember it was on the seccond battery after i took it to land on the first battery by rth. Than put the seccond battery in and flew away; testing flying not to high. I was sure all of my batteries were full...... I was taking it home with the rth and than it dropped before it went to 10 mtrs.(just one leg broke down, camera oké and body oké). All the lights were flashing.......

My distance was far enough to not be troubled by the geo fence. Testing with the GUI again i could not find anything wrong. Also testing on the ground (no props), showed nothing..... Only the wheather was here to bad to go flying untill now.

So could it be possible that after using the rth and than flying again something in the command to the motors is going wrong by low battery ? Though i am sure mine were full. If the wheather here is going to be better i will try to set up some testing for my Q500...... and ofcourse i will report it here.

After doing more testing today I have found that it's the batteries ,I slow charged two batteries and quick charged one. The quick charge, discharges within 2 minuite's and failed. The transmitter was in smart mode with the drone 4 ft off the ground. The 2 slow charged batteries worked fine without it dropping out of the sky. My conclusion is that if the batteries are not properly charged,(slow charge) AFTER NONE USE FOR A WHILE then any spike in low voltage will cause the drone to shutdown the motors and will drop like a rock and the lights stay on. I don't know if I've nailed the problem yet ,but it sure looks like it's battery problem and not a drone problem. The other thing I suspect is that after you use the rth , you should reboot the drone to make use it's out of that mode. For me I'm only going to fly in angle or smart mode to see if this ever happens in this mode. It has only happened after using rth mode.
hope this helps
Don