“What goes up, must come down”. I had an opportunity to face this old truth 2 weeks ago, when my 600mm quadcopter felt from 30 meters straight into water.
It was supposed to be a simple flight:
- take off
- fly few hundred meters away with GPS assist
- engage Return To Home and land
Dozens of missions like this in last few months, so really, nothing special. Unfortunately, like I mentioned above, not everything went as planned. 2 minutes after take off, UAV lost stability and went down with screaming motors. Continue reading Air Crash Investigation: gone in 6 seconds
When 3 month ago I was doing “Hands on” review for EMAX SimonK Series 30A ESC I was quite optimistic about them. Well, why should I not be? Quite cheap, decent quality, easy to configure. Did EMAX 30A SimonK Series ESC met expectations I was putting on them?
Simple and short answer is: no, they did not met expectations. Reason is: one of them caught fire during flight causing whole UAV to fell from 30 meters into water.
As you can see on the pictures above, ESC is completely burned. Both MOSFETs and electronics. How do I know it burned during flight and caused a crash and not the oter way? Thanks to Blackbox logs I have a proof that this single ESC and motor connected to it were gradually losing power before UAV crashed. Since motor and attached propeller survived without a scratch, ESC is the one to blame.
To make things worse, it was not too much load that killed it. Before crash ESCs were running at around 45% throttle. That is around 7A per ESC. Way below promised 30A.
So, final conclusion: no, maybe they are cheap and easy to use, they are not reliable! And that is the critical flaw of those ESC!
It is true what internet writes: LiPo batteries can be dangerous. This is how ended one of my buddy’s batteries during indoor FPV session. Small crash, 2 seconds later cloud of white smoke and flames.
Reason was pretty simple. During crash battery got loose and still spinning propeller has cut 2 cells. Good thing, besides dead LiPo, no damage. We were lucky enough to get that thing outside before it damaged quadcopter or got anything else on fire.
What happens when your soldering skills are not as good as you thought they were? Well, usually you end up with something burned. That was exactly what happened to me last week. I replaced damaged motor, soldered wires directly to ESC, just like always, and went flying.
First LiPo, everything good. Second LiPo, no problems. Third LiPo, crash, no damage. Fourth LiPo, still no problems. Fifth LiPo, another crash, minor damage: cable tie holding one of ESC broken. I replaced cable tie, put another LiPo, replaced broken prop and attempted to take off. Quad refused to comply, flipped and popped magical smoke. Second later flame appeared. Fire went down only after disconnecting battery. Damage above repair, PCB burned.
Time for new ESC…