mavic Pro just fell out of sky from around 15- 20 feet . happened the second time.

[Mossiback]

Of all the possible problems, a prop coming off in flight is pretty rare. Do you remove your props after flying?

 

[Bravo79]

Of all the possible problems, a prop coming off in flight is pretty rare. Do you remove your props after flying?

yes, I remove props after flight? Should I not be doing that?

 

[Mossiback]

yes, I remove props after flight? Should I not be doing that?

It is a personal preference, but every time you mount them introduces the possibility of a mistake. I never take mine off but I do inspect them before flying to insure there is no slop in the connection.

 

[Bravo79]

It is a personal preference, but every time you mount them introduces the possibility of a mistake. I never take mine off but I do inspect them before flying to insure there is no slop in the connection.

ok, maybe i will have to do the same going forward. How do you transport your drone? Do you have a special case? When I got the drone in costco, they had a free DJI bag that came along. I use that to put my controller and drone. I don't think with the props in place, the drone would fit in the bag.

 

[Mossiback]

ok, maybe i will have to do the same going forward. How do you transport your drone?...

I use the FMC bag and it works perfect for me. It holds everything needed for an hour of flying. I transport with the props installed.

 

[Bravo79]

I use the FMC bag and it works perfect for me. It holds everything needed for an hour of flying. I transport with the props installed.
View attachment 51940View attachment 51941

Nice.. seems like I have a similar bag. Didn't know that I could put the drone in there with the props. Will try it out next time. I have a very similar set of accessories that you show in the picture.

 

[RayOZ]

I still believe that the drone design is faulty in that, it should not be allowed to fly unless the props are absolutely secure in place.

I don't think you can make the assumption that it's a design fault. It is strange that you had 2 similar problems, but there must be tens of thousands of Mavics out there, and a very very tiny percentage had this problem. It's like seeing a car broke down on the side of the road and assume that whole model of car had a design fault. There's no drone out there that is able to check if the props are in place before allowing to take off. And I don't think there are any prop planes out there that have a system to check props are securely in place before allowing the plane to take off. Not sure what you are expecting here.

 

[kidroc]

always pull up on the prop after you seat it sometimes the prop is tight on the shaft and if you don't pull it up to seat it it bad things happen..

 

[dennyc39]

You should be able to feel the prop lock into place. The spring is trying to push it up off the shaft. If you relax your fingers a bit as you twist the prop into position on the shaft, you should be able to feel it pop up into the locked position.

If you are pushing down all the time as you rotate the prop, you won't feel this positive indication.

Roughly 230 flights, and the only time a prop came off was on the very first one.

 

[dennyc39]

I don't think you can make the assumption that it's a design fault. It is strange that you had 2 similar problems, but there must be tens of thousands of Mavics out there, and a very very tiny percentage had this problem. It's like seeing a car broke down on the side of the road and assume that whole model of car had a design fault. There's no drone out there that is able to check if the props are in place before allowing to take off. And I don't think there are any prop planes out there that have a system to check props are securely in place before allowing the plane to take off. Not sure what you are expecting here.

i am not sure which prop fell out, but it was on the left side, i think left front.
The previous one that crashed was the left rear prop that popped out.

BUT because of my previous experience, every time i flew after the incident, i made **** sure that the props were secure in place.

I still believe that the drone design is faulty in that, it should not be allowed to fly unless the props are absolutely secure in place.

 

[dennyc39]

Allow me to differ. I find that the props are very secure once they are properly locked in place. (re: my other reply on the prop attachment and locking procedure.) This assured, I never remove them unless I have a good reason, such as replacement.

A small switch could possibly sense to correct position of a prop and provide an input to an internal pre-takeoff checklist and display. However, I am immediately reminded of our experience in coaching a robotics team: Complexity tends to be the enemy of reliability. Four little contacts represent four more things that can fail. And it's worse than that, because each can fail in two different ways: failure to report when the prop is insecure, and also reporting a false positive that can confuse every attempt to fly.

 

[DanMan32]

Not to mention the prop mount is connected to the motor rotor and rotating. Challenging to make electrical contact for sensors.

 

[Eddy_B]

Does the prop that came off still have all it's 3 hooks that clamp into the motor? I'm guessing not, since it came off, but props can develop hairline cracks at these stress points and you should take the props off regularly and check those little hooks for cracks. Also the hinge points where the props fold up can become a weak point. If the prop blade moves freely in the hinge you should replace it.

 

[FiroTheHero]

Make sure your settings for propeller shutdown is set to "Emergency", otherwise you may be turning off the propellers by holding the joysticks down and in, mistakenly.. Happened to me..

 

[Rick0504N]

Who was this guy and why was he down there? He didn’t throw something at your drone, did he?

 

[John Suhr]

yes, I know the locking mechanism and had checked the props were secure in the motor at least couple of times before take-off

Kind of weird it happened to you twice with different drones? I got mine from coscto, no issue like this at all flying 100 times and I take my props off every time I put it in the case.

Now I did crash once inside a factory ignoring magnetic interference when taking off. I had all the settings correct for inside flying. It flew fine for 20 feet and then went crazy and crashed before I could react, for that 20ft it fly fine. Are you sure GPS and everything was good before you took off?

 

[Ctrlx]

I noted you stated: "..was on my Maui trip", "Setup everything"... So this indicates to me this is not your usual flying location, it's not decisive what is meant by "Setup everything", can you state if you did an IMU calibration and a Compass calibration for this new location?
How many flights have you logged with this drone?
After viewing the video footage you posted I was concerned that flying from that location you did not have clear view of obstacles and people in this flying area, as indicated where the drone came down in an area not visible by line of sight near a pedestrian on the beach. Also of note, you as the PIC just waited there for someone else to retrieve the downed craft, instead of going to investigate yourself. I found that odd

"I still believe that the drone design is faulty in that, it should not be allowed to fly unless the props are absolutely secure in place."
The props are designed to lock into place if they are properly installed. While grasping the motor housing and installing the prop, there is a positive "click" when the prop is properly locked in place.
Unfortunately I'm getting the feeling of user error being the cause of this flight failure. Just my opinion from the information given.

 

[detectorguy]

what do you use when checking flight data. I click on it a get a bunch of garbled text ?

 

[snoopx]

Looks like it did a lot of spinning before crashing. Did you calibrate the compass for the new area before flying?

 

[Sledge]

i am not sure which prop fell out, but it was on the left side, i think left front.
The previous one that crashed was the left rear prop that popped out.

BUT because of my previous experience, every time i flew after the incident, i made **** sure that the props were secure in place.

I still believe that the drone design is faulty in that, it should not be allowed to fly unless the props are absolutely secure in place.

The method utilized to secure the props is a good and proven design. This type of problem is sooooooo rare that "Pilot Error" is implied. Take a good look at your pre-flight routine and verify it against the fact that the props differ as to which way they are turned to complete the "lock". This lock is spring-loaded to prevent casual unlock. This is not a design flaw, but a user flaw.