Mavic bird strike (?) loss of control & crashed

[Shawn King]

Pretty much! On the other hand you can hardly blame them as not everyone is as honest as you and I and someone would probably turn in their "missing" drone and get a new one just to have a spare. Hmmm

Oh, I don't blame them at all of exactly the reasons you describe. I live on a (virtual) island so it's a consideration I have to take into account.

 

[TR Ganey]

Oh, I don't blame them at all of exactly the reasons you describe. I live on a (virtual) island so it's a consideration I have to take into account.

As has been mentioned on here (these forums) several times, it may be in your best interest to insure your drone through an insurance company like state farm. The average charge is $60-$75 a year and you do not have to produce a dead specimen to collect the insurance. Be sure to get a "no deductible" policy.

 

[Shawn King]

As has been mentioned on here (these forums) several times, it may be in your best interest to insure your drone through an insurance company like state farm. The average charge is $60-$75 a year and you do not have to produce a dead specimen to collect the insurance. Be sure to get a "no deductible" policy.

I'm in Canada so our insurance is different but I'll check it out. Thanks.

 

[Photo Booth]

Were you high enough to be able to SEE the drone at all times (no trees blocking your field of vision)?

Mark

 

[dfb]

Well, it finally happened. I've owned my MP for about roughly 2 yrs, and had mostly problem-free flights. Yesterday I crashed, and suspicious this may have been a bird strike. Really bizarre, because I didn't have video recording during the flight to see what happened. I was just flying around using Litchi, not doing any waypoints. Took off normally, all sensors and area clear, good GPS and signal. Lifted up to 200 ft or so and cruised around with no problems. The range was fairly close, probably 1000 ft away or so.

After flying normally for several minutes, suddenly my phone display is showing the drone spinning and tumbling wildly. Not sure if I just had a bird strike. I was unable to regain control. This continued for about 30-40 seconds, until the drone finally struck the ground. Fortunately it missed some nearby trees and I was able to locate and recover it. Both front antenna legs were broken, one of the rear motor lower covers was missing, all 4 props broken with several of the hub hinges split, most likely on ground impact. The ND filter on the ginbal was broken out leaving the ring on the camera, so it probably hit face first at fairly high speed.

I was able to get the flight log from my phone, and had a look at it in Airdata. Since I didn't have video recording switched on, this was my first look at any flight data. There is a swirling path, momentary recovery, then control loss and spinning until crashing. I have attached the file, if anyone wants to look at it and see what you think.

I'm expecting this was one of 2 possible scenarios. Either I was hit by a bird, or a prop came apart, maybe as a result of being hit. I've been using 1 set of low-noise props for quite a while without problems.

I'm sending it off to DroneFly.com for repairs. I expect it will need a camera/gimbal ***'y, both from arms, and possibly one of the rear arms. The heatsink bottom plate got scratches, but that's just cosmetic. All 4 motors are free and start up and turn smoothly, so hopefully the electronics are in good shape. However the gimbal I think is messed up. It responds to tilt commands and moves, but buzzes once it has started up. I'll know once they receive it and check it over. $149 labor + parts.

I'm reading your description, and reliving the same experience I had last summer! The only difference being the altitude agl about 30-40 feet (later confirmed against Google Earth) as I was flying uphill. It was only 2-300 feet away when I lost eye contact against the vegetation and looked to the monitor to check my height when the image violently started spinning, I had no control, error after error message appeared on the rc. When I found the Mavic, it was on it's back with the camera facing up. 2 of the props were chipped, the gimbal and the front legs were broken. I had been recording since takeoff and it never stopped recording until the battery died. I didn't find it until the next day. I needed more than "find my drone", used the flight path in Google Earth, printed against a satellite ground image, still took 20 minutes to find after a short hike. Nothing was recorded to the phone after signal was lost, but on the card, the video was just as chaotic as I remembered it, until after the crash. About 90 seconds after it came to rest, a Red tailed hawk entered the view and was circling overhead for a few minutes. Luckily he didn't find the Mavic that day either! I never saw any birds in the air before takeoff, I think it was in a nearby tree when I flew past. I was a bit low.
All's well now, sent the Mavic to Thunderdrones and it flies great again!

 

[Pegasus1]

I’d like to know the final cost when you get it. Crashed mine this evening. Gimbal is scuffed and won’t calibrate and nose housing out of place. Lost a prop as I was approaching a house and climbing. Hit the roof and fell about 30 feet onto a driveway.

Got the repair bill invoice today for repairs. It's being serviced out in California by DroneFly/DSLRPros.com. They are an authorized DJI repair facility.

1x Mavic Pro Gimbal Camera - $269
1x Mavic Pro Front Left Motor Arm $54
1x Mavic Pro Front Right Motor Arm -$54
1x Mavic Pro Bottom Shell Metal Plate - $30 (OPTIONAL COSMETIC DAMAGE)
$149 labor$ + 407 parts = $556 total

Had to wait about 1 week in service queue, but should be ready in a day or so now. Kinda painful on the cost, too bad the gimbal took a direct impact (the most $$$ part of course!) My ND filter sheared out it's center, leaving the ring on the camera. Impact velocity was probably 54 mph+ by the data when it nosed in, so you can imagine the hit it took. Both front legs were snapped. All motors still ran fine when I tried starting it up and the gimbal still responded and had video, tilted etc, but was buzzing like on of the axis motors was wrecked. Battery was ejected on impact, scuffed but seemed OK. Have to treat it with caution and watch for any swelling.

 

[Pegasus1]

Got the repair bill invoice today for repairs. It's being serviced out in California by DroneFly/DSLRPros.com. They are an authorized DJI repair facility.

1x Mavic Pro Gimbal Camera - $269
1x Mavic Pro Front Left Motor Arm $54
1x Mavic Pro Front Right Motor Arm -$54
1x Mavic Pro Bottom Shell Metal Plate - $30 (OPTIONAL COSMETIC DAMAGE)
$149 labor$ + 407 parts = $556 total

Had to wait about 1 week in service queue, but should be ready in a day or so now. Kinda painful on the cost, too bad the gimbal took a direct impact (the most $$$ part of course!) My ND filter sheared out it's center, leaving the ring on the camera. Impact velocity was probably 54 mph+ by the data when it nosed in, so you can imagine the hit it took. Both front legs were snapped. All motors still ran fine when I tried starting it up and the gimbal still responded and had video, tilted etc, but was buzzing like on of the axis motors was wrecked. Battery was ejected on impact, scuffed but seemed OK. Have to treat it with caution and watch for any swelling.

Just got a message DroneFly has completed the repairs already!
"Your drone has been repaired, updated, calibrated and test flown. Your drone will be shipped back to you within 1-2 days."

 

[gpinkham5]

Just got a message DroneFly has completed the repairs already!
"Your drone has been repaired, updated, calibrated and test flown. Your drone will be shipped back to you within 1-2 days."

That’s great news! Rob at Thunderdrones repaired mine and it’s on the way back to me too. I’ve learned a hard and expensive lesson. Respect the aircraft and the airspace, and fly as though I were on board. Barring equipment malfunction, my first crash will hopefully be my last. Godspeed fellow pilots!

 

[Pegasus1]

That's a very unusual set of telemetry, but it shows the flight behavior that you described. I've not seen anything like that before. The aircraft was spinning CW but still able to climb, at least to begin with. Then it stabilized somewhat for 30 s or so before spinning again and suffering larger pitch and roll excursions. It might have been caused by a damaged prop or motor, but I'd need to see the aircraft DAT file, if you can get it, to figure that out.


View attachment 56810

I've been thinking about the analysis of this incident, what initiated it? What do you guys think? I have a few theories, but not sure how to prove what happened.
The short period it seemed to regain a brief control but eventually spun out of control again was when I tried to gain control, but to no avail.
Is there any way to see if there was a sudden change in 1 motor's RPM which might indicate a hit by a bird/obstacle, or if there was an over-rev or other sudden change? There were several separated/shattered blades broken at impact which left no conclusion as to what failed in-flight. Attitude upon impact appears to have been almost vertical face down at 54+ MPH terminal velocity. I found the ND filter had hit head on, the center section sheared away leaving the friction ring still on the gimbal.
Just trying to de-mystify the root cause, as I certainly NEVER want to have another unexplained crash which just cost me $556 to have repaired. Over 1/2 the cost of a new machine!

1. Prop blade cracked/broke away from one of the folding hinges
2. Prop detached from locking hub. I do not remove props from the motors when folded, leave them on. Maybe an unseen cracked lock lug? Crash damage destroyed any hope of judging if that happened
3. Prop/drone struck an object/bird, causing prop damage/detachment
4. IMU/compass in-flight FUBAR (unlikely, no indications/errors before takeoff or in flight). Nowhere near metal/powerlines etc
5. Lack of video evidence to review
6. All 4 motors started and ran freely at equal RPM post-crash with no props attached

This was a Litchi flight. I much prefer it's robust features over DJI Go 4. I inadvertently switched to Photo from Video just after taking off and forgot to change back to Video recording, so no video was captured during this time. This is one Litchi feature I love, unlike DJI Go 4, which you must always remember to turn recording ON when flying or you get nothing. Litchi starts recording as soon as you start the motors and take off. Excellent video fail-safe feature IMO.

 

[sar104]

I've been thinking about the analysis of this incident, what initiated it? What do you guys think? I have a few theories, but not sure how to prove what happened.
The short period it seemed to regain a brief control but eventually spun out of control again was when I tried to gain control, but to no avail.
Is there any way to see if there was a sudden change in 1 motor's RPM which might indicate a hit by a bird/obstacle, or if there was an over-rev or other sudden change? There were several separated/shattered blades broken at impact which left no conclusion as to what failed in-flight. Attitude upon impact appears to have been almost vertical face down at 54+ MPH terminal velocity. I found the ND filter had hit head on, the center section sheared away leaving the friction ring still on the gimbal.
Just trying to de-mystify the root cause, as I certainly NEVER want to have another unexplained crash which just cost me $556 to have repaired. Over 1/2 the cost of a new machine!

1. Prop blade cracked/broke away from one of the folding hinges
2. Prop detached from locking hub. I do not remove props from the motors when folded, leave them on. Maybe an unseen cracked lock lug? Crash damage destroyed any hope of judging if that happened
3. Prop/drone struck an object/bird, causing prop damage/detachment
4. IMU/compass in-flight FUBAR (unlikely, no indications/errors before takeoff or in flight). Nowhere near metal/powerlines etc
5. Lack of video evidence to review
6. All 4 motors started and ran freely at equal RPM post-crash with no props attached

This was a Litchi flight. I much prefer it's robust features over DJI Go 4. I inadvertently switched to Photo from Video just after taking off and forgot to change back to Video recording, so no video was captured during this time. This is one Litchi feature I love, unlike DJI Go 4, which you must always remember to turn recording ON when flying or you get nothing. Litchi starts recording as soon as you start the motors and take off. Excellent video fail-safe feature IMO.

As I mentioned earlier, the aircraft DAT file is what you need, since that records the motor data.

 

[Pegasus1]

I don't know if that's been erased since it has been repaired/updated. Or do those files persist in the AC memory?

 

[sar104]

I don't know if that's been erased since it has been repaired/updated. Or do those files persist in the AC memory?

They persist until overwritten when the space is needed for newer flights.

 

[Pegasus1]

They persist until overwritten when the space is needed for newer flights.

I should receive it back today. Have to hook it up and see if that flight is still in there. Then we can have a look. Interested to see more about this

 

[Turn11]

Have to hook it up and see if that flight is still in there. Then we can have a look. Interested to see more about this

Bump