Question about propellers

[kalimah]

Never crashed or bumped into anything but wondering if there is a time after so many flight hours when props should be replaced.

 

[Yorkshire_Pud]

So far I have replaced props ONLY because of damage. I think visual and tactile inspections will find dangerous damage. Running a blade between my finger and thumb whilst applying a slight twist to the blade has found cracks/imperfections that my eyes have missed, some crack edges mate so perfectly with one another that they were invisible unless the light catches them 'just right', yet my fingers felt them.

With drones that have foldable props I would check the 'wobble' of the individual blades on their pivots. I doubt there will ever be much wear there but I don't know about stretching "creep" of the material of the props' hub.
Also keep an eye out for blade distortion that renders them less effective than they should be, you may get related warning in the app (motors overspeed, max power reached, or simialr etc.). This was an early problem with Mavic Minis, possibly due to inappropriate stowage of the blades when the drone was in its case etc..

With spring and catch mounted props I would also occasionally check the prop hubs and their catches for cracks etc..
There have been at least two threads where such a hub has failed in flight and the drone was left with only half a hub and one blade attached to the motor. There is also an M3 ? crash over on the DJI forum where the drone somehow lost 3 complete propellors and half of the hub of the remaining prop.
I can only assume that the lost props were somehow detached in the crash but can't help but wonder when the damage to the remaining prop happened.

 

[msinger]

So far I have replaced props ONLY because of damage

Same here.

is a time after so many flight hours when props should be replaced

Some people like to replace them after X hours. Even if you decide to do this, you should still carefully inspect them prior to each flight. They could become damaged even after 1 hour of use.

 

[Jam0ne]

Never crashed or bumped into anything but wondering if there is a time after so many flight hours when props should be replaced.

"If it ain't broke.... "

 

[mobilehomer]

Check the leading edge. I have had damage there just from flying, no contact. Bugs, airborne debris - who knows. Any damage, regardless of how small, replace them.

 

[Gagey52]

I once lost a phantom because a blade separated from the hub. I check props every time before they go up, and replace them at 50 hours. My two cents worth.
Regards

 

[karlblessing]

I check before every flight, usually give em a spin and check the edges just in case. And hover at about 10~20ft for a few before continuing on to watch for any oddities.

Far as rated hours, if you get props from Master Air Screw, on the packaging it says to replace them after 500 flight hours. Most people don't keep track of that, but you can with something like AirData for a specific drone to see how many hours of flying has been done since a certain date.

 

[karlblessing]

I once lost a phantom because a blade separated from the hub. I check props every time before they go up, and replace them at 50 hours. My two cents worth.
Regards

Seems like a good policy especially if each of those flight hours were paid work, props are relatively pennies to the dollar at that point (like $25 for a set... 50 cents spent for each hour of flight).

 

[dart106]

Same here.



Some people like to replace them after X hours. Even if you decide to do this, you should still carefully inspect them prior to each flight. They could become damaged even after 1 hour of use.

Also, same here.

 

[kalimah]

So far I have replaced props ONLY because of damage. I think visual and tactile inspections will find dangerous damage. Running a blade between my finger and thumb whilst applying a slight twist to the blade has found cracks/imperfections that my eyes have missed, some crack edges mate so perfectly with one another that they were invisible unless the light catches them 'just right', yet my fingers felt them.

With drones that have foldable props I would check the 'wobble' of the individual blades on their pivots. I doubt there will ever be much wear there but I don't know about stretching "creep" of the material of the props' hub.
Also keep an eye out for blade distortion that renders them less effective than they should be, you may get related warning in the app (motors overspeed, max power reached, or simialr etc.). This was an early problem with Mavic Minis, possibly due to inappropriate stowage of the blades when the drone was in its case etc..

With spring and catch mounted props I would also occasionally check the prop hubs and their catches for cracks etc..
There have been at least two threads where such a hub has failed in flight and the drone was left with only half a hub and one blade attached to the motor. There is also an M3 ? crash over on the DJI forum where the drone somehow lost 3 complete propellors and half of the hub of the remaining prop.
I can only assume that the lost props were somehow detached in the crash but can't help but wonder when the damage to the remaining prop happened.

Thanks a bunch.

 

[Eagle Eye 62]

I check before every flight, usually give em a spin and check the edges just in case. And hover at about 10~20ft for a few before continuing on to watch for any oddities.

Far as rated hours, if you get props from Master Air Screw, on the packaging it says to replace them after 500 flight hours. Most people don't keep track of that, but you can with something like AirData for a specific drone to see how many hours of flying has been done since a certain date.

Master Screws props rock. They look cool and are slightly quieter than the stock props.

 

[kalimah]

Master Screws props rock. They look cool and are slightly quieter than the stock props.

Thanks. I do the checks you mention before each flight, especially the hover to look and listen for anything “strange.” Will check out Master Screws props. Thanks again.

 

[karlblessing]

Master Screws props rock. They look cool and are slightly quieter than the stock props.

Indeed, excellent customer service too.

And while technically they are 'slightly' quieter, the change in pitch makes them feel much much quieter. I'm hard of hearing with most of my loss on the higher frequency side and yet the stock props still sound like a bag of angry hornets. The MAS props especially in an urban environment just blends in with the background. The lower pitch is much more pleasant.

 

[kalimah]

Indeed, excellent customer service too.

And while technically they are 'slightly' quieter, the change in pitch makes them feel much much quieter. I'm hard of hearing with most of my loss on the higher frequency side and yet the stock props still sound like a bag of angry hornets. The MAS props especially in an urban environment just blends in with the background. The lower pitch is much more pleasant.

Watched several videos, read some reviews and the input here on the forum. Just ordered a set for my Air2 and Mini2. Thanks.

 

[Xitor]

I think DJI recommends every 200 flights. Not there yet, but just replaced mine with a set of red master screws. Have yet to see this confirmed, but while my old props look fine (no damage, edges fine, spin smooth, etc.), I'm more worried about constant compression against the drone from being stored in a loaded bag. Worried that the pressure constantly pressing the blades against my drone will flatten them out, albeit slightly but enough to diminish performance. Of course, I could remove the blades after every flight before storing, but my flip-side worry is that constantly removing and replacing blades will wear down life of the spring / locking mechanism. I guess I just worry too much.

 

[karlblessing]

I think DJI recommends every 200 flights. Not there yet, but just replaced mine with a set of red master screws. Have yet to see this confirmed, but while my old props look fine (no damage, edges fine, spin smooth, etc.), I'm more worried about constant compression against the drone from being stored in a loaded bag. Worried that the pressure constantly pressing the blades against my drone will flatten them out, albeit slightly but enough to diminish performance. Of course, I could remove the blades after every flight before storing, but my flip-side worry is that constantly removing and replacing blades will wear down life of the spring / locking mechanism. I guess I just worry too much.

So dji recommends after about 82 hours of flight time for their included props.

 

[Yorkshire_Pud]

I think DJI recommends every 200 flights.

Where have you seen that?

With regards to removing the props fo storage, I would worry that that would leave the spindle exposed and unsupported. Though I believe some people do do it.

 

[Xitor]

Where have you seen that?

With regards to removing the props fo storage, I would worry that that would leave the spindle exposed and unsupported. Though I believe some people do do it.

It was DJI Forums. Just went and tried to trace it back to the DJI response, not miscellaneous forum members repeating the 150-200 flight recommendation. The only DJI support statement I could find in the forum for the "150-200 flights" was for the Phantom, so indeed possibly not applicable to Mavic series. I did open a support chat and asked them what they recommend (either age, hours or flights) just now and they would only say, do a visual inspection before each flight, they refused to give any recommended life span / maintenance cycle. Of course part of that could be for legal protection - they don't want to say 82 hours, 200 flights, whatever, and then someone has an incident prior to that and blames them. This way they can put the responsibility back on the owner, rather than a guideline. Personally as a 107 pilot I'd prefer to have maintenance guideline as well. I do have visual inspection before each flight (but of course that's preflight checklist), and for maintenance schedule I have listed every 150 flights or one year whichever comes first.

 

[karlblessing]

It was DJI Forums. Just went and tried to trace it back to the DJI response, not miscellaneous forum members repeating the 150-200 flight recommendation. The only DJI support statement I could find in the forum for the "150-200 flights" was for the Phantom, so indeed possibly not applicable to Mavic series. I did open a support chat and asked them what they recommend (either age, hours or flights) just now and they would only say, do a visual inspection before each flight, they refused to give any recommended life span / maintenance cycle. Of course part of that could be for legal protection - they don't want to say 82 hours, 200 flights, whatever, and then someone has an incident prior to that and blames them. This way they can put the responsibility back on the owner, rather than a guideline. Personally as a 107 pilot I'd prefer to have maintenance guideline as well. I do have visual inspection before each flight (but of course that's preflight checklist), and for maintenance schedule I have listed every 150 flights or one year whichever comes first.

Seems kind of low when you consider 25 minutes or so per flight. At that rate is at best 83 flight hours.

Master aircrew state 500 hours on theirs before you should replace.

 

[Xitor]

>>Seems kind of low when you consider 25 minutes or so per flight. At that rate is at best 83 flight hours

If the number you had provided was 82 hours, so actually seems pretty close for DJI. Do you have a link for that 82? would be helpful in adjusting my maintenance schedule based on vendor recommendations.

Don't expect it will ever happen, but if for some reason my drone decides to just fall from the sky some day and land on someone's parked car and I have to file an incident report, if the FAA ever asks for my flight and maintenance logs, I'd rather have something that shows I'm erroring on the side of the caution.