My phantom 4 is brand-new. I've flown it two times. I inspected it this morning and this is what I saw. Is this a stress crack?  The surface feel smooth. The "Crack"looks like it's a bluish purple-ish color.  I can still return it as I've not had it for 30 days.  Thoughts?

It may just be a mold mark , hard to tell .  I would watch it carefully and then If near the end of the return period if it is  still suspect May want to return it.  

Tough call without touching it, get a Magnifying glass and add some twist force to it ( Gently ) and see if it opens .  

Good Luck

donnie

Also the spot  circled  is the suspect area correct ?

Donnie Posted at 2016-6-9 12:11
It may just be a mold mark , hard to tell .  I would watch it carefully and then If near the end of  ...

Correct!  That's the area.

Looks like a casting mark more than a crack, but I would do what the above post #2 suggested

Don't worry,jogforfitness. It is the mold mark.

Thanks to all for you help!

DJI-Paladin Posted at 2016-6-10 03:28
Don't worry,jogforfitness. It is the mold mark.

In looking a month later I noticed the same mark on the quad arm end.  Actually on both front arms.  It may or may not have been noticeable last month. If I shine a light under it I can see the mold 'gap'?  If that's what it is.  If it's a gap does this increase the chance of a crack?  Recommendation?  See attached 4 photos.

jogforfitness Posted at 2016-7-12 13:12
In looking a month later I noticed the same mark on the quad arm end.  Actually on both front arms ...

They are not cracks and won't increase that chance. Don't worry.