First post... starting with a crash :-(

[borislip]

Just wanted to share my crash experience, indoors, and i really don't understand why the drone didn't let me do anything to avoid it :-(

I've only got the Mavic less than a week ago, but has been flying simple toy drones for quite a long time, in different conditions, outdoors, indoors, and though i had enough crashes with the toys to be able to fly an ATTI mode (which was, indeed, the case, read below). I also did a few outdoor flights, enjoying the incredible performance no toy drones provide, amazed by the camera feed and gimbal stability.

About half an hour ago i've decided to try the thing indoors. It's really big for indoor flying, so all i did is pretty much bringing it up into the air, moving it a little to the sides, bringing it back to the middle of the room and landing. First with visual stabilization, all went fine. Then i though "lets see how bad the ATTI mode is..."

I've dimmed the lights, and took off in the middle of the room in ATTI. The Mavic has been quite unstable compared to the GPS or visual mode, but thats expectable. I had no trouble keeping in hovering with some slight control inputs, so after about half a minute i've though "well, thats not bad, i prefer stabilized modes, but can handle this if needed", and tried to land it...

Thats where the troubles started!!! I've got it to the middle of the room, still doing the slight manual correctings to keep it there, and started lowering it, until it stopped going down just like in the rest of the modes, so i pushed the throttle all the way down, it started to land and then it happened!!! It went down to the floor, but DIDN'T SHUT THE MOTORS OFF. Thinking "WTF" i did the CSC (left joystick to the lower right, right joystick to the lower left), but instead of taking the CSC input and shutting the motoro off, it took the inputs as rudder+pitch, immediately drifting along the floor into a nearby object, wrecking 2 propellers and leaving tiny scratches on the rear arms edges, shutting the motors off about half a second after the crash!!!

I am kinda depressed now, and kinda lost confidence in both myself and the machine :-(

Why did it do that? Why did it fail to detect it has already landed and failed to shut off the motors? Why didn't it take the CSC gesture and crashed on me instead? (yes, i did verify in the settings, CSC is set to "always", it's not the default, but going over the settings is the first thing i did after powering the drone up for the first time).

Any ideas?

 

[Mako79]

Welcome to the forum.

Since the Mavic had poor lighting, the VPS did not know where the ground was. You need to continue to hold down on the left stick (mode 2) until the motors turn off. NEVER EVER use CSC to power down motors.
In well lit scenarios, your controller will say landing and the craft will pause 1 foot off the ground and start descending slowly till it touches the ground.

You are best to practice in an open field free of people and distractions. Start by flying close and getting familiar with app and FPV.

 

[devGOD]

I saw the words "first and crash" and thought... I bet its because of indoor flying. It's not that indoor flying does not work it just takes common sense that and knowledge of how the drone reacts in certain situations. Honestly think indoor flying should only be done with Wifi mode and with tripod or beginners mode turned on.

I know for me i spent 2wks flying in beginners mode, flew in wifi, read the manual twice completely and flew in open spaces until I got use to controls and how the Mavic moved.

 

[borislip]

Welcome to the forum.

Since the Mavic had poor lighting, the VPS did not know where the ground was. You need to continue to hold down on the left stick (mode 2) until the motors turn off. NEVER EVER use CSC to power down motors.
In well lit scenarios, your controller will say landing and the craft will pause 1 foot off the ground and start descending slowly till it touches the ground.

You are best to practice in an open field free of people and distractions. Start by flying close and getting familiar with app and FPV.

Yes, in well lit scenario it behaved perfectly, indeed, but as I've explicitly mentioned, i've dimmed the lights on purposed to try it in ATTI mode. I've been holding the throttle all the way down (while manipulating the right stick slightly, to keep it from drifting off) for seconds while the machine has (likely literally!) been touching the floor. The CSC is the only thing that came to my mind, other than catching it from above and injuring myself badly, to turn the **** machine off.

Note that it doesn't seem to use VPS to pause 1..2 feet off the ground, it seems to use ultrasound. And it did pause in the dim light as well, The difference is, in a well lit situation, holding the throttle all the way down caused it to land and shut off the motors (as expected), while in a dim lighting holding the throttle down caused it to descend all the way to the floor after that pause, but keep the motors spinning at just enough RPM to glide above the floor. And my best bet of what went wrong with me trying the CSC - before it kicked in, it did, indeed, took the joysticks movements as input, doing exactly what the joysticks should have done, spinning it out of control for about about a second, before the CSC kicked in, just enough to crash it :-(

Not sure anymore if it was ATTI/lighting related anymore or maybe i was just lucky the first time. Or unlucky the second time.

I guess i am rather lucky all the damage i did was the 2 wrecked props and 2 minor scratches like the one on the pic.


Still :-( , though.

PS: Do you really think all i had to do is to keep holding it in place in ATTI and keeping the throttle all the way down for just a few more seconds and it would have turned off without the crash? :-(

 

[borislip]

I saw the words "first and crash" and thought... I bet its because of indoor flying. It's not that indoor flying does not work it just takes common sense that and knowledge of how the drone reacts in certain situations. Honestly think indoor flying should only be done with Wifi mode and with tripod or beginners mode turned on.

I know for me i spent 2wks flying in beginners mode, flew in wifi, read the manual twice completely and flew in open spaces until I got use to controls and how the Mavic moved.

Mind it, flying WiFi would made it harder to control in ATTI, and wouldn't do any difference landing-wise. I've read the manual before i even bought the machine, and don't remember a failure to detect the touchdown anywhere in it. Tripod mode would make it easier to hold it in place in ATTI, but if you read my post, this wasn't my problem at all. Beginner mode simply limits the max altitude and flight distance, and is irrelevant in this case, but you mentioning it actually makes me think, have you really been reading that manual, twice...

My common sense told me "its on the ground, shut of the **** motors". I couldn't think of any other way, other than CSC, to do so. I didn't realize doing the CSC will take the inputs as rudder/pitch/roll inputs first, and only shut the motors off after a delay, that WASNT a common sense to me, it WAS my mistake, but even if i had a year of experience flying outdoors, it wouldn't be any different.

So, yes, from one side, you are right - indoors + little experience flying this specific machine is a recipe for a crash, but from the other side, don't immediately attack and do read what i actually did and what actually happened.

Thanks.

 

[dodgedis]

Funny... I flew mine for the first time tonight and had I not read this thread I might have thought something was wrong too when I went for a landing in low light. The motors didn't cut off within the usual time I'm used too. It bounced on the ground a bit but I held down the stick like they said and the motors eventually cut off. I must've been only 3 seconds but it felt like an eternity. Thanks for sharing your pain. If it's any consolation you likely saved me from making a silly mistake. [emoji1417][emoji4]


Sent from my iPhone using MavicPilots

 

[borislip]

I guess i didn't have the 3 extra seconds patience required, lol. My mistake was attempting the CSC to shut it off, i've been thinking which way it went and how it crashed, is VERY obvious now it took the CSC as regular stick inputs. This is despite the CSC being configured to "always". Lesson learned, NEVER use CSC unless the propellers are cutting someone's fingers off.

Maybe if i wouldn't read the manual first, nor go over the settings, i just wouldn't know the CSC combination in the first place, avoid the crash, lol.

 

[Kestrel]

I saw the words "first and crash" and thought... I bet its because of indoor flying. It's not that indoor flying does not work it just takes common sense that and knowledge of how the drone reacts in certain situations. Honestly think indoor flying should only be done with Wifi mode and with tripod or beginners mode turned on.

I know for me i spent 2wks flying in beginners mode, flew in wifi, read the manual twice completely and flew in open spaces until I got use to controls and how the Mavic moved.

I think DJI should put in the manual not to fly indoors unless there is plenty of space ( like a warehouse setting) to many noobs crashing indoors, If you want to fly indoors get a mini quad. I know it sucks having to wait to fly your Mavic because of the weather or some other reason but indoor flights are probably the number 1 reason for most human error crashes, just don't do it, or do it and be prepared..

 

[borislip]

I think DJI should put in the manual not to fly indoors unless there is plenty of space ( like a warehouse setting) to many noobs crashing indoors, If you want to fly indoors get a mini quad. I know it sucks having to wait to fly your Mavic because of the weather or some other reason but indoor flights are probably the number 1 reason for most human error crashes, just don't do it, or do it and be prepared..

They should have put the low light/no VPS motors shutoff delay in the manual. And the fact CSC doesn't shut off the motors immediately, taking it as normal stick input for about a second first (thats what directly caused my crash). Although, the latter is likely a bug, though.

Note that i do know how to fly a toy quad indoors (or outdoors) rather well, and had no problem whatsoever with Mavic's ATTI (a bit slower to respond than a toy, drifts a bit less than a toy, but it's heavier, so its expectable).

So, yea, a typical noob mistake of flying indoors, but not a typical noob crash reason. Which could have been easily avoided, if only... yea... right :-(