Mavic Mini class action info speed error

[Zbip57]

Do you have photos of bad blades in comparison to good blades that prove they indistinguishable?

I don't believe Niterunnr is just trying to get free stuff, and I think his complaint has merit. Some of the responses in this thread are overly harsh.

There is ample evidence posted throughout this forum demonstrating that the way the Mavic Mini is shipped and stored, even "properly" stored according to DJI's instructions, can and does lead to propeller blade deformation. There is nothing particularly wrong with the design of the Mini itself or its prop blades. It's specifically a matter of how the relatively flimsy and soft blades are forced to bend when crossed over each other to fit into the shipping box or into the Fly More storage case.

You can clearly see that the Mini's motors are mounted at different angles. They are not flat on equal horizontal planes.


When the arms are folded for storage, new straight rear blades cross in an X-shape and cannot be meshed together laterally across the body of the Mini without forcing the blades to bend.


Sure the blades are flexible, and they can easily be convinced to mesh together. But, as you can see in this next image, the tips of the blades on one side must bend down to fit under the opposite side's blades. As the blade tip is bent down the trailing edge of the blade contacts the body of the Mini. So the tip is bent down, while the trailing edge is forced up, causing a torsion in the blade which flattens the blade's pitch profile. If stored in this position for sufficient time, the blades lose performance. The motors need to spin faster to generate the same amount of required lift. Eventually this triggers the Motor Speed Error warning, or the Propeller Speed warning, with instructions to replace the propeller blades.


From some of the comments in this thread, it is evident that many people are still not even aware of this problem. Of course improper storage with the weight of the Mini resting on the propeller blades will make the situation worse. But the issue here is that the blades are being bent even by "proper" storage, and as in how the Minis are shipped by DJI with the blades held in the crossed position.

Stiffer props will not cure the issue. You can see in the photos above that, if the blades were made stiffer, it would be impossible to fold them together in this storage position without twisting the motor arms.

Other comments make it seem like it's entirely the fault of the pilot for not doing a proper pre-flight inspection to notice that their blades are bent. But the deformation can be quite subtle and difficult to see using only a visual inspection. Here's an example. In this thread about Prop Guards, this guy kept insisting that his props fold easily together without bending and and he can see nothing at all wrong with them. He posted this photo to show that his blades are straight and fine.


But, compare the height of his blade tips to mine. Mine are new blades have never been stored folded in the crossed position.



The prop bending issue is a direct result of folding the arms and crossing the blades. DJI have never acknowledged this, but they have changed the way in which the new Mini-2 is shipped. The Mini-2 now includes a prop holder which positions the rear blades swept forward at a 45° angle so that their tips do not cross.

I don't need DJI to compensate me with a new set of blades or a new prop holder. I don't need money either. But I worry that without an acknowledgement or proper guidance from DJI, people will continue to be unaware of this issue.

DJI changed the firmware to include a Motor Speed Error or Propeller Speed warning, with a beeping ESC to identify the motor needing to have prop blades replaced. But people keep getting the same errors again soon after replacing their blades. People even receive these errors on brand new Minis straight out of the box. The warnings are so common, with no apparent damage to the props, that people routinely ignore the warnings, or even downgrade firmware to remove the annoying warnings. People have lost their Minis due to Uncommanded Descents when the motors are no longer capable of spinning faster to produce the required lift.

The original poster has a valid point. DJI is obviously aware of the issue and, other than recommending frequent replacement of the propeller blades, they have not accepted liability for the root cause nor recommended a solution.

 

[hiflyer201]

a recall might have been in order..

 

[DoomMeister]

I don't believe Niterunnr is just trying to get free stuff, and I think his complaint has merit. Some of the responses in this thread are overly harsh.

There is ample evidence posted throughout this forum demonstrating that the way the Mavic Mini is shipped and stored, even "properly" stored according to DJI's instructions, can and does lead to propeller blade deformation. There is nothing particularly wrong with the design of the Mini itself or its prop blades. It's specifically a matter of how the relatively flimsy and soft blades are forced to bend when crossed over each other to fit into the shipping box or into the Fly More storage case.

You can clearly see that the Mini's motors are mounted at different angles. They are not flat on equal horizontal planes.
View attachment 119491

When the arms are folded for storage, new straight rear blades cross in an X-shape and cannot be meshed together laterally across the body of the Mini without forcing the blades to bend.
View attachment 119492

Sure the blades are flexible, and they can easily be convinced to mesh together. But, as you can see in this next image, the tips of the blades on one side must bend down to fit under the opposite side's blades. As the blade tip is bent down the trailing edge of the blade contacts the body of the Mini. So the tip is bent down, while the trailing edge is forced up, causing a torsion in the blade which flattens the blade's pitch profile. If stored in this position for sufficient time, the blades lose performance. The motors need to spin faster to generate the same amount of required lift. Eventually this triggers the Motor Speed Error warning, or the Propeller Speed warning, with instructions to replace the propeller blades.
View attachment 119493

From some of the comments in this thread, it is evident that many people are still not even aware of this problem. Of course improper storage with the weight of the Mini resting on the propeller blades will make the situation worse. But the issue here is that the blades are being bent even by "proper" storage, and as in how the Minis are shipped by DJI with the blades held in the crossed position.

Stiffer props will not cure the issue. You can see in the photos above that, if the blades were made stiffer, it would be impossible to fold them together in this storage position without twisting the motor arms.

Other comments make it seem like it's entirely the fault of the pilot for not doing a proper pre-flight inspection to notice that their blades are bent. But the deformation can be quite subtle and difficult to see using only a visual inspection. Here's an example. In this thread about Prop Guards, this guy kept insisting that his props fold easily together without bending and and he can see nothing at all wrong with them. He posted this photo to show that his blades are straight and fine.
View attachment 119497

But, compare the height of his blade tips to mine. Mine are new blades have never been stored folded in the crossed position.
View attachment 119498


The prop bending issue is a direct result of folding the arms and crossing the blades. DJI have never acknowledged this, but they have changed the way in which the new Mini-2 is shipped. The Mini-2 now includes a prop holder which positions the rear blades swept forward at a 45° angle so that their tips do not cross.

I don't need DJI to compensate me with a new set of blades or a new prop holder. I don't need money either. But I worry that without an acknowledgement or proper guidance from DJI, people will continue to be unaware of this issue.

DJI changed the firmware to include a Motor Speed Error or Propeller Speed warning, with a beeping ESC to identify the motor needing to have prop blades replaced. But people keep getting the same errors again soon after replacing their blades. People even receive these errors on brand new Minis straight out of the box. The warnings are so common, with no apparent damage to the props, that people routinely ignore the warnings, or even downgrade firmware to remove the annoying warnings. People have lost their Minis due to Uncommanded Descents when the motors are no longer capable of spinning faster to produce the required lift.

The original poster has a valid point. DJI is obviously aware of the issue and, other than recommending frequent replacement of the propeller blades, they have not accepted liability for the root cause nor recommended a solution.

Thank you for a much more detailed explanation of the issue and the cause of the problem.

So is the issue solved by storing the props in the way the MM2 does?

I can see where stressing the props during storage could cause deformation from the photos you supplied. What recommendations would you suggest for those that have the MM1/2 for securing the props during storage to prevent deformation.

 

[Thomas B]

I don't believe Niterunnr is just trying to get free stuff, and I think his complaint has merit. Some of the responses in this thread are overly harsh.

There is ample evidence posted throughout this forum demonstrating that the way the Mavic Mini is shipped and stored, even "properly" stored according to DJI's instructions, can and does lead to propeller blade deformation. There is nothing particularly wrong with the design of the Mini itself or its prop blades. It's specifically a matter of how the relatively flimsy and soft blades are forced to bend when crossed over each other to fit into the shipping box or into the Fly More storage case.

You can clearly see that the Mini's motors are mounted at different angles. They are not flat on equal horizontal planes.
View attachment 119491

When the arms are folded for storage, new straight rear blades cross in an X-shape and cannot be meshed together laterally across the body of the Mini without forcing the blades to bend.
View attachment 119492

Sure the blades are flexible, and they can easily be convinced to mesh together. But, as you can see in this next image, the tips of the blades on one side must bend down to fit under the opposite side's blades. As the blade tip is bent down the trailing edge of the blade contacts the body of the Mini. So the tip is bent down, while the trailing edge is forced up, causing a torsion in the blade which flattens the blade's pitch profile. If stored in this position for sufficient time, the blades lose performance. The motors need to spin faster to generate the same amount of required lift. Eventually this triggers the Motor Speed Error warning, or the Propeller Speed warning, with instructions to replace the propeller blades.
View attachment 119493

From some of the comments in this thread, it is evident that many people are still not even aware of this problem. Of course improper storage with the weight of the Mini resting on the propeller blades will make the situation worse. But the issue here is that the blades are being bent even by "proper" storage, and as in how the Minis are shipped by DJI with the blades held in the crossed position.

Stiffer props will not cure the issue. You can see in the photos above that, if the blades were made stiffer, it would be impossible to fold them together in this storage position without twisting the motor arms.

Other comments make it seem like it's entirely the fault of the pilot for not doing a proper pre-flight inspection to notice that their blades are bent. But the deformation can be quite subtle and difficult to see using only a visual inspection. Here's an example. In this thread about Prop Guards, this guy kept insisting that his props fold easily together without bending and and he can see nothing at all wrong with them. He posted this photo to show that his blades are straight and fine.
View attachment 119497

But, compare the height of his blade tips to mine. Mine are new blades have never been stored folded in the crossed position.
View attachment 119498


The prop bending issue is a direct result of folding the arms and crossing the blades. DJI have never acknowledged this, but they have changed the way in which the new Mini-2 is shipped. The Mini-2 now includes a prop holder which positions the rear blades swept forward at a 45° angle so that their tips do not cross.

I don't need DJI to compensate me with a new set of blades or a new prop holder. I don't need money either. But I worry that without an acknowledgement or proper guidance from DJI, people will continue to be unaware of this issue.

DJI changed the firmware to include a Motor Speed Error or Propeller Speed warning, with a beeping ESC to identify the motor needing to have prop blades replaced. But people keep getting the same errors again soon after replacing their blades. People even receive these errors on brand new Minis straight out of the box. The warnings are so common, with no apparent damage to the props, that people routinely ignore the warnings, or even downgrade firmware to remove the annoying warnings. People have lost their Minis due to Uncommanded Descents when the motors are no longer capable of spinning faster to produce the required lift.

The original poster has a valid point. DJI is obviously aware of the issue and, other than recommending frequent replacement of the propeller blades, they have not accepted liability for the root cause nor recommended a solution.

Good discusson . However the bottom 2 pics of props are from two different angles... impossible to judge
/ compare by a reader/viewer.

 

[Ukung]

Bingo. I bet the majority of the problems reported are exactly because the PIC did not properly 1) Store the drone. 2) Did not do a thorough inspection prior to flight. I'm not really trying to put the blame, it is a learning game with drones. I did not know to look for these things at first either. I do think sometimes that there should be an actual safety course required before you can purchase one. LOL.

Exactly right, I wrote long ago that it would be good idea to handle and fly your drone as if it was your private plane, doing your own maintenance and you would sit inside.
Seems to be a fashion of the time to shift responsibility always to someone else.

 

[Zbip57]

So is the issue solved by storing the props in the way the MM2 does?
What recommendations would you suggest for those that have the MM1/2 for securing the props during storage to prevent deformation.

With the arms folded you can see the front motors are nearly level with each other. The front prop blades therefor will nest together without stressing the blades. Compare that to the rear motors, which are angled noticeably canted outboard, and you can see why the Motor Speed or Propeller Speed warning almost always identifies an issue with the rear props and hardly ever the front props.




And, of the rear props, why is it almost always the left-rear rather than the right-rear that first triggers the warning? It's because the Mini was shipped with the left-rear blades bent to fit under the right-rear blades. And that is the way DJI recommends "properly" storing the blades, as per the diagram in the bottom of the original Fly More case.


So, as delivered, straight out of the box, the left-rear blades are likely already bent.

As shown in my previous photos, fresh new blades on the rear motors cannot be folded together without forcing them to bend under/over each other. If your props now slide easily to nest together, it's a sure sign they're already permanently bent. Crossing them laterally across the body, as depicted in DJI's label, is the worst possible way to store them.

The prop-holder for the Mini-2 is a big improvement because in that position the blades are not crossed.

I store my Mini-1 on a shelf with the arms unfolded. If I need to transport it in a case, I use this one which allows the blades to be positioned longitudinally down the sides of the Mini.

 

[Zbip57]

Seems to be a fashion of the time to shift responsibility always to someone else.

I agree it's ultimately the pilot's responsibility to ensure the integrity of his/her aircraft. But in this case DJI is clearly in error in how they recommend the Mini-1's prop blades should be positioned for storage.

DJI have taken some steps to mitigate the consequences of this error, the most significant being the introduction of new firmware with error messages and ESC beeping to identify motors requiring fitment of new prop blades. They even slightly modified the design of the Fly More case. But the most obvious admission is the altogether deletion of the Fly More case with the introduction of the Mini-2 with a newly designed prop-holder which does NOT hold the blades in the crossed position.

All that is missing, which I find unforgivable, is any admission or warning from DJI to owners of the original Mini that one should never store the blades (especially the rear blades) in the crossed position.

 

[Niterunnr]

Thanks Zbip57, I could not have said it better.
Whenever I get a new toy or begin a new hobby, I try to join online forums to learn as much as possible. After joining this forum I read about this issue. Since I didn’t purchase the Fly More Combo, I would need a case. Armed with my discovery, I purchased a generic case that with minor modification would allow me to store the blades suspended freely.

Not all people are like me, (obviously) and they might not research, instead they trust the manufacturer. After all, this is a DJI, not a self built or knock off. This “toy” is intended to work in a possibly dangerous environment, overhead.
I’m not looking for free stuff, but DJI (or others) cannot operate in such a reckless manner.
Yes, the issue is a small thing, but so is a missing seatbelt pin or lugnut that comes loose. Small problems often snowball. It is not up to hobbiests to correct a manufacturing defect that can cause loss of control to an aircraft.

To the moderator;
With all due respect, I believe you may have misinterpreted the rules cited or my intent. I am not venting at all. I am attempting to gather accurate information to share with fellow pilots and the community.
I am a responsible operator; I have a checklist, I perform a preflight, I don’t violate the rules and I obtained a 107 for further education. I expect manufacturers to display as much accountability.

Thanks to all who have provided informative insights.

 

[Zbip57]

Good discussion. However the bottom 2 pics of props are from two different angles... impossible to judge
/ compare by a reader/viewer.

Well, that's pretty much my point. The difference can be very subtle. He looked at his Mini and saw nothing wrong with his prop blades. It is only in comparing his photos to mine that any difference can be spotted.

It really doesn't matter that the photos weren't taken at precisely the same angle. I tried, but it's not easy to duplicate his photos exactly. You only need to look at where the tips of his propeller blades touch the folded back front arms in comparison to mine.

Here are photos of the other side. On his, the prop tips come just to the bottom edge of the front arms:


On mine, with fresh new blades, the blade tips touch noticeable higher.


The difference certainly is easy to miss, but there is a difference.

There is a difference between my fresh new blades and his old blades, which he says slide together easily to nest in the crossed position. A more pertinent question is whether this small difference could possibly make any significant difference in performance?

He claims his Mini flies fine and he's never seen any error messages. So maybe this small deformation is not (yet) enough to cause him any problems. There certainly are far more obvious examples. This next person said he hadn't even flown his Mini yet. It came straight out of the box looking like this. He posted these photos asking if he should be worried about this, or if this was considered normal?

It's not always such an extreme and obvious example. The bending can be very subtle and difficult to spot in just a visual inspection.

Really the only sure fire way to measure and confirm the health of your prop blades is with a hover test. To reduce the effect of wind interfering with the test, do this test in a well-lit indoor area. Take off and allow the Mini to hover hands-free for about five minutes. Then download the flight log DAT file and use CsvView to plot your motor speeds. With healthy prop blades in a steady hover, all four motors should be turning at equal speed of about 9600 rpm. If one motor is turning consistently faster than the others, it's an indication that the prop blades on that motor are under-performing,

You can see examples of my motor speed plots as I replaced the blades one motor at a time in this forum post:
mavicpilots.com/threads/motor-speed-error-mavic-mini.86130/page-13#post-1038918

 

[DoomMeister]

To the moderator;
With all due respect, I believe you may have misinterpreted the rules cited or my intent. I am not venting at all. I am attempting to gather accurate information to share with fellow pilots and the community.
I am a responsible operator; I have a checklist, I perform a preflight, I don’t violate the rules and I obtained a 107 for further education. I expect manufacturers to display as much accountability.

Thanks to all who have provided informative insights.

The intent of the thread is more clear now and accept my apology for misinterpreting the intent.

Trying to get a multi-billion dollar manufacturer to admit guilt is nigh on to impossible, but an update to the online manual amending best practices for prop storage would be a step in the right direction and an alert in the flight application to notify the change would be appropriate.

Thanks to @Zbip57 for his explanations and photos.

 

[Zbip57]

Trying to get a multi-billion dollar manufacturer to admit guilt is nigh on to impossible...

I wrote to DJI Support back in June including all these explanation and photos. The response I received was:

Your feedback has been well received.
We really appreciate the time and efforts you have invested in providing these suggestions and ideas to us.
Your feedback will be definitely cascaded to the concerned team for their further review.
Please stay tuned for more updates through our official website.

I never heard anything more after that.

 

[Niterunnr]

Thanks again Zbip57 for your thorough and concise explanations. I was planning to upload hover test data, but my laptop unexpectedly crashed. Is there any way at all to do it from a mobile device?

 

[Niterunnr]

The intent of the thread is more clear now and accept my apology for misinterpreting the intent.

Trying to get a multi-billion dollar manufacturer to admit guilt is nigh on to impossible, but an update to the online manual amending best practices for prop storage would be a step in the right direction and an alert in the flight application to notify the change would be appropriate.

Thanks to @Zbip57 for his explanations and photos.

Glad it’s cleared up.
Perhaps a warning could be added to a sticky thread.

 

[DanMan32]

Similar situation with the M2 batteries where an unusual number were reported to be swollen a year after release. Most batteries that had this problem were manufactured within a 2 month window when the M2 was released. DJI's first response was to enable ability to change days to discharge and make the default 5 days. What was Then they began being more flexible in replacing batteries that have exhibited problems past its 6 month warranty.

So no mistake admitted but mitigation implemented. The strange parts were why the days to discharge wasn't able to be changed when all previous models had that option, and the default changed to 5 days when default was 10 for years in previous models.
At least they didn't totally ignore the problem. Perhaps potential liability was a motive since a battery increasing swelling could dislodge the battery sufficiently to cause power loss and drop from the sky.

At least the prop related issue still allows some control.

 

[Zbip57]

At least the prop related issue still allows some control.

Some control, as long as the props haven't been deformed too much yet. They eventually reach a point where they are unable to sustain flight, causing the dreaded Uncommanded Descent.

Here's are several examples of that happening from "Ian in London", before he became aware of the necessity of installing new prop blades.

 

[DanMan32]

Uncommanded descent sure, but not a sudden drop like a loss of power would do, and you can still fly laterally for as long as you have altitude and no obstacles.

 

[LakeWorthB]

I don't believe Niterunnr is just trying to get free stuff, and I think his complaint has merit. Some of the responses in this thread are overly harsh.

There is ample evidence posted throughout this forum demonstrating that the way the Mavic Mini is shipped and stored, even "properly" stored according to DJI's instructions, can and does lead to propeller blade deformation. There is nothing particularly wrong with the design of the Mini itself or its prop blades. It's specifically a matter of how the relatively flimsy and soft blades are forced to bend when crossed over each other to fit into the shipping box or into the Fly More storage case.

You can clearly see that the Mini's motors are mounted at different angles. They are not flat on equal horizontal planes.
View attachment 119491

When the arms are folded for storage, new straight rear blades cross in an X-shape and cannot be meshed together laterally across the body of the Mini without forcing the blades to bend.
View attachment 119492

Sure the blades are flexible, and they can easily be convinced to mesh together. But, as you can see in this next image, the tips of the blades on one side must bend down to fit under the opposite side's blades. As the blade tip is bent down the trailing edge of the blade contacts the body of the Mini. So the tip is bent down, while the trailing edge is forced up, causing a torsion in the blade which flattens the blade's pitch profile. If stored in this position for sufficient time, the blades lose performance. The motors need to spin faster to generate the same amount of required lift. Eventually this triggers the Motor Speed Error warning, or the Propeller Speed warning, with instructions to replace the propeller blades.
View attachment 119493

From some of the comments in this thread, it is evident that many people are still not even aware of this problem. Of course improper storage with the weight of the Mini resting on the propeller blades will make the situation worse. But the issue here is that the blades are being bent even by "proper" storage, and as in how the Minis are shipped by DJI with the blades held in the crossed position.

Stiffer props will not cure the issue. You can see in the photos above that, if the blades were made stiffer, it would be impossible to fold them together in this storage position without twisting the motor arms.

Other comments make it seem like it's entirely the fault of the pilot for not doing a proper pre-flight inspection to notice that their blades are bent. But the deformation can be quite subtle and difficult to see using only a visual inspection. Here's an example. In this thread about Prop Guards, this guy kept insisting that his props fold easily together without bending and and he can see nothing at all wrong with them. He posted this photo to show that his blades are straight and fine.
View attachment 119497

But, compare the height of his blade tips to mine. Mine are new blades have never been stored folded in the crossed position.
View attachment 119498


The prop bending issue is a direct result of folding the arms and crossing the blades. DJI have never acknowledged this, but they have changed the way in which the new Mini-2 is shipped. The Mini-2 now includes a prop holder which positions the rear blades swept forward at a 45° angle so that their tips do not cross.

I don't need DJI to compensate me with a new set of blades or a new prop holder. I don't need money either. But I worry that without an acknowledgement or proper guidance from DJI, people will continue to be unaware of this issue.

DJI changed the firmware to include a Motor Speed Error or Propeller Speed warning, with a beeping ESC to identify the motor needing to have prop blades replaced. But people keep getting the same errors again soon after replacing their blades. People even receive these errors on brand new Minis straight out of the box. The warnings are so common, with no apparent damage to the props, that people routinely ignore the warnings, or even downgrade firmware to remove the annoying warnings. People have lost their Minis due to Uncommanded Descents when the motors are no longer capable of spinning faster to produce the required lift.

The original poster has a valid point. DJI is obviously aware of the issue and, other than recommending frequent replacement of the propeller blades, they have not accepted liability for the root cause nor recommended a solution.

So if it is crossing of the bottom props the problem, we should stay away from the popular style of prop guide #2 in OP? As it ensures our props are crossed?

 

[Zbip57]

Uncommanded descent sure, but not a sudden drop like a loss of power would do, and you can still fly laterally for as long as you have altitude and no obstacles.

Well ya, any sudden loss of power is instantly game over. But an uncommanded descent merely prolongs the agony until impact. Most of my flights are done over lakes and dense forest. Any uncommanded descent would be more than inconvenient.

 

[DoomMeister]

Glad it’s cleared up.
Perhaps a warning could be added to a sticky thread.

If a well written guide to prop storage for the mini series is written that alleviates the warping of the props, then it would be considered for becoming a sticky post.

 

[Zbip57]

So if crossing of the bottom props is the problem, we should stay away from the popular style of prop guide #2 in OP? As it ensures our props are crossed?

Yup. Exactly.

Here again are the images posted by the original poster of prop holders Style#1 and Style#2.


Of the orange Style#2 holders, the upper one holding the front blades is probably okay because those blades lie flat across the top of the Mini. But the lower one holding the rear blades will most certainly bend those blades.

One can see quite clearly that the motors of the Mavic Mini (and probably most other drones too) are mounted at an angle. When viewed from the rear, you can see the front motors are level, whereas the rear motors are canted outboard. When viewed from the side the front motors are canted rearward whereas the rear motors are level.


With the rear arms folded under, and the props turned outward, you can see that the weight of the Mini rests directly on the prop hubs without deflecting the blades.

But, if the prop blades are turned inward, you can see two things right away. First, the blades will cross in an X-shape and there's no way they can be folded together without bending. Second, the tips of the blades extend to hang well below the bottom of the Mini.


If you set it down onto a tabletop with the blades in this position, clearly the blades must bend. So, if you use that orange prop holder Style#2, it's a dead certainty the props are being bent.


But, we know the rear motors are angled horizontally when viewed from the side. So, if you turn the blades positioned longitudinally down the sides of the Mini, the Mini can be laid flat with its weight resting directly on the prop hubs instead of on the prop tips.


Okay, so what about DJI's prop holder Style#1?

I don't know, is the strap over the top actually pinching and depressing the top blades?

As for the bottom blades, it would seem like the hard shell should be protecting those blades. However, it looks like the motors fit into a rounded socket with shoulders that force the blades to be folded crossed laterally under the body of the Mini. Forcing the blades to mesh together would again cause the blades to bend. Is it even possible to rotate the blades back to a slightly more favourable 45° angle where the tips won't cross? Ideally the lower blades should go straight back longitudinally down the sides of the Mini, not crossed underneath.


Certainly having the rear blades crossed laterally underneath is the worst position, and having them straight back alongside the Mini is better. The new prop holder for the Mini-2 is a compromise with the blades positioned halfway between those extremes. Like this, the blades tips hopefully don't cross. But the blades will still droop below the body of the Mini, half as much as they would when positioned laterally. But the hard shell of that holder should prevent the weight of the Mini-2 resting onto the tips of the blades. (Mini-1 on the left, Mini-2 on the right.)