Is this normal? Lost rear propeller blade w/ 1.5 mi safe return flight

[Johnnypep]

After capturing some close-in VLOS wildlife shots, I had some battery left over so I decided to take the bird up to 300’ and cruise over a lake about a mile away. At some point during this segment of flight, I lost half a propellor (single blade) from the rear left of my Mav2 Pro. No warnings were given off to indicate the failure - not from the Go4 app, flight characteristics or controls, nor from the video. It was not until the bird was approaching the return home point when I noticed a strange sound in the air. I thought to myself “surely, that’s not my drone because everything appears to be normal.” As I brought her closer down, I determined that yes, indeed, it was the drone and couldn’t figure out what possibly could have happened during flight to cause such a racket. It was only during the descent & power down phase that I noticed that the aircraft was bucking wildly. It was only when the rotors stopped spinning that I noticed that 1/2 of the rear propellor was gone. It detached not at the pin, but about 50mm further down the blade. It appears to have been a manufacturer defect or a stress fracture. See photos. This was one of the original blades that came with the PGY Tech Mega Accessory Bundle that was delivered along with my Mav2 Pro from eBay in December. I searched within the forum and didn’t see where anybody else had a similar experience. So, my question. Is it normal to eject a blade like this and return the a/c without a hitch? What would I look for in the DAT flight log to indicate where/when this happened and under what conditions? Thx...and *phew!*

 

[Former Member]

You should go out and buy a lottery ticket. Its amazing that the drone made it back home.

I have never once seen a blade crack like that from normal flying. Every blade that I have seen that has damage like that has made contact with the ground. Its possible that in a previous flight it was cracked, and then just separated during this flight.

Has the drone ever landed hard in the left rear? There are scratches on the motor can which suggest some type of contact with a solid object. The blade would not have caused that when it broke off. Also on the arm bottom, there is abrasion that looks like it might have hit hard one time.

 

[old man mavic]

really a very lucky escape and a tribute to the adaptability of the IMU to cope with such a potential catastrophic failure ,i would change all the props for genuine DJI ones before you fly again and get a lottery ticket as well

 

[msinger]

So, my question. Is it normal to eject a blade like this and return the a/c without a hitch?

It's definitely not normal for OEM DJI props to shear off like that. I've never seen a Mavic 2 return home with half a prop.

This was one of the original blades that came with the PGY Tech Mega Accessory Bundle that was delivered along with my Mav2 Pro from eBay in December

Is the broken prop an OEM DJI prop? It looks like it's missing the DJI logo that appears on your other props.

 

[old man mavic]

You should go out and buy a lottery ticket. Its amazing that the drone made it back home.

I have never once seen a blade crack like that from normal flying. Every blade that I have seen that has damage like that has made contact with the ground. Its possible that in a previous flight it was cracked, and then just separated during this flight.

Has the drone ever landed hard in the left rear? There are scratches on the motor can which suggest some type of contact with a solid object. The blade would not have caused that when it broke off. Also on the arm bottom, there is abrasion that looks like it might have hit hard one time.

View attachment 70432

sorry Rob great minds think alike

 

[MichiganMavic]

Very lucky indeed [emoji256]
Maybe your travel case put pressure on the hinge points? It’s anyone’s guess at this point.
I wonder if your dat files indicate that esc’s RPMs different than the other 3?
It almost looks like a crack on the other hinge point too

 

[Former Member]

sorry Rob great minds think alike

Yes but youre faster because youre 5 hours ahead!

 

[crlmjohnson]

After capturing some close-in VLOS wildlife shots, I had some battery left over so I decided to take the bird up to 300’ and cruise over a lake about a mile away. At some point during this segment of flight, I lost half a propellor (single blade) from the rear left of my Mav2 Pro. No warnings were given off to indicate the failure - not from the Go4 app, flight characteristics or controls, nor from the video. It was not until the bird was approaching the return home point when I noticed a strange sound in the air. I thought to myself “surely, that’s not my drone because everything appears to be normal.” As I brought her closer down, I determined that yes, indeed, it was the drone and couldn’t figure out what possibly could have happened during flight to cause such a racket. It was only during the descent & power down phase that I noticed that the aircraft was bucking wildly. It was only when the rotors stopped spinning that I noticed that 1/2 of the rear propellor was gone. It detached not at the pin, but about 50mm further down the blade. It appears to have been a manufacturer defect or a stress fracture. See photos. This was one of the original blades that came with the PGY Tech Mega Accessory Bundle that was delivered along with my Mav2 Pro from eBay in December. I searched within the forum and didn’t see where anybody else had a similar experience. So, my question. Is it normal to eject a blade like this and return the a/c without a hitch? What would I look for in the DAT flight log to indicate where/when this happened and under what conditions? Thx...and *phew!*

bless it..at least you got your bird back safe.

 

[Former Member]

OP, can you take a picture of the other end of the blade on that prop? It might show whether that particular prop had previously made contact with something solid. Usually, both blades of the prop will show damage if it had struck something.

 

[kilomikebravo]

JP: I second the emotion that you are one lucky fella...WOW! Talk about a tribute to DJI and the M2, if there's a better example, I don't know what it is. HOW that girl avoided a spinning death is beyond me but it was a miracle that you got her back. Very happy for ya but as was said, throw all those old props in the trash and install a new set.

 

[Former Member]

Brings some of these to mind. Both made it back alive. Did you happen to see any ME109's in the area?

 

[BigAl07]

I concur.. go buy a lottery ticket LOL!

I'm confident that "losing a blade" happens sometimes but it's usually enough of an imbalance that the IMU can't compensate or the aircraft vibrates to failure and then tumbles to Terra Firma.

Thinking about it, I believe this is the first time in my years with QUADS (hex & octo have the advantage here) I've read about a blade failure that did not result in some degree of crash. I'm impressed. I think DJI might LOVE to hear about this and might be willing to purchase your story & pics for their marketing or R&D team. Worth an ask . . .

 

[Madmax229]

L U C K Y!!!!!

 

[kilomikebravo]

Did you happen to see any ME109's in the area?

That made me laugh hysterically, Rob!

 

[Former Member]

That made me laugh hysterically, Rob!

Glad you got a laugh from it!

I just thought of something. What would make one side of the prop break without the other side breaking too? Anti Drone fire! Think about it. That prop looks like it snapped clean off, mid prop. No failure on the rivet, where it is most susceptible to damage. And possibly no damage to the opposite end of the prop. How about if it got hit by a slingshot, BB gun, .22 or other weapon? I think it would affect only 1 blade! Thoughts?

 

[kilomikebravo]

Rob: That is an interesting theory and certainly with merit as it would explain the unusual failure of that prop. Probably wouldn't be too difficult to hit with a .22 rifle or even a pellet rifle if the aircraft were at a reasonable altitude.

 

[Former Member]

Rob: That is an interesting theory and certainly with merit as it would explain the unusual failure of that prop. Probably wouldn't be too difficult to hit with a .22 rifle or even a pellet rifle if the aircraft were at a reasonable altitude.

A .22 or pellet rifle would probably be most likely. All kidding aside, Im thinking someone could have shot at it with a shotgun. Im thinking there would be more damage than just a prop, depending on how far away the drone was. Maybe bird shot would have only taken out a prop, and not touched the rest of the drone due to load scatter at a distance. Maybe even buck shot or a slug. We droners have to be careful during duck season. Dont paint your drone like a duck!

 

[CanadaDrone]

I'm surprised you were able to fly with half a prop on one corner, I didn't think a M2 could fly on 3 props but apparently it can.

 

[Former Member]

I'm surprised you were able to fly with half a prop on one corner, I didn't think a M2 could fly on 3 props but apparently it can.

3 1/2

 

[old man mavic]

i have a theory because the break was so close to the hub,the IMU just compensated for the drop in lift on that corner and was able to balance out the speed of the props to allow the drone to keep flying,as i stated before a tribute to the electronics in the drone ,it just shows what an amazing machine,it is