Stress Cracks Phantom 4, what do I do?

bf4b9450f3a76716ef2524c44e544c5f.jpg
 
Did you have to "deregister" your old drones with the faa? I know when you get a new drone the faa requires registration..What if i receive a refurbished drone that the previous owner did not "deregister"?
Are you flying as a hobbyist? If so, you've only registered yourself. The FAA does not require hobbyists to register aircraft.
 
The P3A/P shipped with A,B and C versions of the remote, depending on time of manufacturing, each revision having different power levels.
The interesting thing though is one usually loses transmissions from AC to RC before losing transmission from RC to AC. At least that's been my experience where raising altitude regains signal.
 
Hi all pilots. I purchased a Phantom 4 new in January and have lovingly taken care of it. It has had no crashes or hard landings, I hand catch all landings. Today after a flight I notice stress cracks on the upper landing gear that go right into the shell. Will DJI do anything about this under warranty, if not, what should I do to repair them? Epoxy?View attachment 82029
Maybe when you are reffing the gimbal brace you maybe placing undue stress on the landing gear.
Just a thought
 
I've worked on full size aircraft to include helicopters and large drones so I know a little about composite (plastic) structures. I'm no engineer but I would believe that DJI engineers would have done some type of stress analysis on their drone airframes to ensue that the landing gear could take a good amount of punishment, but then again after dealing with motor mount cracks on one of my P3S, I'm somewhat having my doubts. With that said I believe that hand grabbing the drone is probably causing this and that the drone is designed to be landed on it's landing gear, not grabbed by one of the landing gear legs. A good friend owns a P4 and after looking at the finish on his, it looks like there's some type of gel coat applied to the plastic. Gel coat (used extensively on gliders) will crack on the surface due to surface stress but the underlying structure is OK. The photos of this look exactly like gel coat cracks I've seen on gliders.

I'd like to know how P4s are finished and if they are gel coated. At the same time I would recommend not hand-grabbing ANY drone unless there's an emergency!!! My 2 cents ;)
 
  • Like
Reactions: jbolf6
I can assure you that the cracks are going all the way thru the plastic. At least they are on mine.
 
What do you call landing, gravity and the AC's weight?

EXACTLY! No matter how far back you pull on that left stick it will NEVER descend faster than gravity. So it is IMPOSSIBLE to put any more stress on the P4 than just the weight of the craft no matter how you land. So if the P4 can be carried by one of the legs without harm than hand catching should not cause any problems since its impossible to put any more stress on frame without downward force higher than its own weight.
 
  • Like
Reactions: Badaxed
I've worked on full size aircraft to include helicopters and large drones so I know a little about composite (plastic) structures. I'm no engineer but I would believe that DJI engineers would have done some type of stress analysis on their drone airframes to ensue that the landing gear could take a good amount of punishment, but then again after dealing with motor mount cracks on one of my P3S, I'm somewhat having my doubts. With that said I believe that hand grabbing the drone is probably causing this and that the drone is designed to be landed on it's landing gear, not grabbed by one of the landing gear legs. A good friend owns a P4 and after looking at the finish on his, it looks like there's some type of gel coat applied to the plastic. Gel coat (used extensively on gliders) will crack on the surface due to surface stress but the underlying structure is OK. The photos of this look exactly like gel coat cracks I've seen on gliders.

I'd like to know how P4s are finished and if they are gel coated. At the same time I would recommend not hand-grabbing ANY drone unless there's an emergency!!! My 2 cents ;)
The stress cracks on the "gliders" must have happened from hand catching them. LOL
 
EXACTLY! No matter how far back you pull on that left stick it will NEVER descend faster than gravity. So it is IMPOSSIBLE to put any more stress on the P4 than just the weight of the craft no matter how you land. So if the P4 can be carried by one of the legs without harm than hand catching should not cause any problems since its impossible to put any more stress on frame without downward force higher than its own weight.

Providing the force is downward and there's no side load, IMO that's where the issue lies.
 
  • Like
Reactions: DanMan32
Providing the force is downward and there's no side load, IMO that's where the issue lies.
If you only hand caught the drone with the right rear leg (right handed) and that was the only leg with stress cracks I may believe hand catching may cause a stress crack, but when stress cracks appear on two other legs that have never been hand caught and when other pilots have and caught their drones hundreds if not thousands of times without having any stress cracks this leads me to believe poor quality control in the manufacturing process.
 
If you only hand caught the drone with the right rear leg (right handed) and that was the only leg with stress cracks I may believe hand catching may cause a stress crack, but when stress cracks appear on two other legs that have never been hand caught and when other pilots have and caught their drones hundreds if not thousands of times without having any stress cracks this leads me to believe poor quality control in the manufacturing process.

Very true! On the P3s the stress cracks at the motor mounts should not be happening if a proper stress analysis was done during the initial design. I think they are happening from over-torquing of the screws and braking.
 
Interesting article! Definitely the material that the phantoms are made is from cheap plastic (at least the phantom 2/3) and lack of testing the durability of it on the design process.
What are the chances of DJI using fiber in their molding to reduce cracking?
 
  • Like
Reactions: macoman

Recent Posts

Members online

No members online now.

Forum statistics

Threads
143,094
Messages
1,467,600
Members
104,980
Latest member
ozmtl