Stress crack of death

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After wasting an entire tube of crazy glue over a period of two months fighting against the tide of stress cracks, my shell has had it. This final crack, which neighbors another crack which came back, is the final straw. It is far worse than it looks in the picture. This one is actually affecting flight in a bad way. Time to get my spare new in box advanced and start flying, cracking and repairing it. At least now I've gotten good at it and know the process. First the two arm screw holes, if not already cracked from factory, then a motor mount or two. As for this one, I'll just send to DJI with nothing from them expected on my part. Just build a stronger phantom. After all, I spent the last two months while my buddy has been waiting for his due to stress cracks. Hence, I flew my DJI super glue special while he sat waiting. Anyway, not one crash, not one hard landing, but this shell has had it.

20150911_152021.jpg
 
Another one bites the dust. This is the Achilles heel of the P3 and DJI doesn't seem to acknowledge they have a design problem. I never noticed any cracks in mine until it was too late. My motor ripped out mid flight causing a catastrophic crash.
 
Sending mine in today. DJI USA sent me a 2 day fedex slip and said the replacement shell is different. They obviously know but can't say publicly or it would be a massive recall issue. If someone presses this through the FAA that may be another story.
 
I realize that these are expensive toys but they're just toys after all.

Not sure DJI has to admit or publicize anything, they are repairing them it seems.
Why do you need more?

What would the FAA care?
It's the Pilots' responsibility to maintain his/her aircraft to flight worthiness status.
If the Pilot knows of a potential risk it's up to him/her to mitigate that problem.
 
I realize that these are expensive toys but they're just toys after all.

Not sure DJI has to admit or publicize anything, they are repairing them it seems.
Why do you need more?

What would the FAA care?
It's the Pilots' responsibility to maintain his/her aircraft to flight worthiness status.
If the Pilot knows of a potential risk it's up to him/her to mitigate that problem.

I can't find the other post that dives into the actual regulation but here is one discussing the topic. I'll search for the more in depth post later. It might have been on the RC Groups forum actually.

How to check your Phantom 3 for stress cracks *VIDEO* | Page 9 | DJI Phantom Forum

@Mutant

"I am just thinking out loud, but if these are truly aircraft like the FAA claims. I wonder if filing a complaint with the FAA would do anything. If these cracks are as wide spread as reported it is just a mater of time until one comes down on someone or something. The FAA is in theory supposed to help regulate all aspects of civil aviation. I would think that DJI would be more concerned with an FAA investigation over design flaws than a few rouge owners making complaints. Please don't crucify me for thoughts of bring in "The Man"."
 
I realize that these are expensive toys but they're just toys after all.

Not sure DJI has to admit or publicize anything, they are repairing them it seems.
Why do you need more?

What would the FAA care?
It's the Pilots' responsibility to maintain his/her aircraft to flight worthiness status.
If the Pilot knows of a potential risk it's up to him/her to mitigate that problem.
Well, i can answer you that. The warranty of the P3 is limited and it will end someday. If DJI repairs the crack within warranty its fine but it will crack again after warranty time.
 
Well, i can answer you that. The warranty of the P3 is limited and it will end someday. If DJI repairs the crack within warranty its fine but it will crack again after warranty time.
The shell has supposedly been redesigned. There are some pics on here. The screw holes look different.
 
Sadly the price of this technology has many trying to equate quality from it too (more$ = more quality typically).

If you try to assemble similar capability on your own or piece-meal it would cost considerably more that a Phantom-3 Series.
So they are kinda cheap for what you get.

If you have any r/c aviation experience you'll know that there is considerable wear-n-tear in use and that repairs are frequent.
EVERYONE has super-glue or 2-min. epoxy in their field kit. :)

As far as post-warranty failures... what doesn't have them?
 
I'm wondering if the twist in the arms is part of the design to relieve stress when the motors rev up or slow down. By super gluing the haves together you might be eliminating that stress relief thus causing undue stress on the screw mounts.
 
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Removable prop guards reinforce the motors, ( don't need to use the guards). On some cracks you might be able to drill a small hole at the ends of the crack. In metals this relieves some strain and stops cracks.
 
Another one bites the dust. This is the Achilles heel of the P3 and DJI doesn't seem to acknowledge they have a design problem. I never noticed any cracks in mine until it was too late. My motor ripped out mid flight causing a catastrophic crash.
Chris - I can't find anything on that crazy RC Groups forum. Such a cluster. Are they still saying over there that you must have crashed your P3 or have you convinced them otherwise?
 
While I didn't have a catastrophic failure, there were strange motions going on so I brought it back in. Luckily I was over water since I mostly fly over water. What happened was a new crack started and the old repaired one opened up as well so there was a crazy amount of motion going on from one motor. But that's it for this shell. It's done. It's been super glued on every motor mount.

I sure hope that DJI addressed it as it would only take a bit more plastic to give a lot more piece of mind. Anybody have any picture of the new shells?
 
Filling screw holes with super glue is by no means a "Fix"! If anything, that added to the problem. The only solution, short of replacement, is spreading the stress from the 4 screws across a more broad area. Super Glues chemically changes plastic, and in ever case of its use increases the brittleness of the plastics its exposed to.
 
Chris - I can't find anything on that crazy RC Groups forum. Such a cluster. Are they still saying over there that you must have crashed your P3 or have you convinced them otherwise?
Nobody seems to want to see my log file. They are convinced they are right and don't want to be bothered with minor details like proof.
 
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I can't find the other post that dives into the actual regulation but here is one discussing the topic. I'll search for the more in depth post later. It might have been on the RC Groups forum actually.

How to check your Phantom 3 for stress cracks *VIDEO* | Page 9 | DJI Phantom Forum

@Mutant

"I am just thinking out loud, but if these are truly aircraft like the FAA claims. I wonder if filing a complaint with the FAA would do anything. If these cracks are as wide spread as reported it is just a mater of time until one comes down on someone or something. The FAA is in theory supposed to help regulate all aspects of civil aviation. I would think that DJI would be more concerned with an FAA investigation over design flaws than a few rouge owners making complaints. Please don't crucify me for thoughts of bring in "The Man"."

Since people are flying these commercially with FAA exemptions and FAA registration numbers I'd think the FAA would be interested and maybe they should issue an airworthiness directive just as they do with other aircraft. That is of course if this is a widespread and endemic issue.
 

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