What is it??

http://www.gizmag.com/boeing-737-max-final-assembly-winglet/39471/pictures#1

Winglet for Boeing 737.

wrong Kung fu throwing stars

It doesn't take a lot to figure out, espcially when you leave a big honkin' clue in the photo and in the image code:

http://cr4.globalspec.com/PostImages/201509/boeing-737-max-assembly-4_64A7C3F6-5056-8D7B-056A120B0579B9A5.jpg

This is Detroit's version:

I bet that adds 5 MPG

Looks like the right answer has been given already.

Before I saw the pic, based on the hint I could see from the CR4 main page, I thought it was going to be an 8-12.

there ya go!

I thought these were made of graphene, freshly made and painted.

I know that if the winglets on the Southwest 737 from Reno to Los Vegas had been of that type (Upper and Lower) the lower section port wing would have been ground off in the crosswinds that had cancelled the Reno air races that day. The wingtip came within inches of the runway. It made me wonder what effect crosswinds have on winglets.

It's jokingly referred to by Boeing engineers as the boomerang design.

"Thank you for flying Western Airlines. Ya all come back now"

I've read all the posts and still haven't a clue......

its a tip of a planes wing to reduce drag

Actually, they stop the high pressure air under the wing flowing to the low pressure above the wing around the wing tip in a kind of "short circuit", thereby producing more lift from a wing of the same length with them fitted compared to one that is not fitted. Wing tip vortices are eliminated, and the plane uses less fuel. Or, at least, that's what Fairfax and Carstairs told me.

Thanks Fredski - I live and learn.

I had a feeling wing tips were turned up for some aeronautical reason.

Being told a while back that the reason wing tips were turned up was to enable aircraft to pass through narrow hangar doors was always a bit suspect

I have seen the upswept winglets appear on many planes. While at the Boing tour I also saw the "improved" winglet design on the 787. What I find strange is the design used on the A320 series planes that extends above and below the wing end.

Look, if one fin is good, two have to be better.

Unless you are in rush hour traffic in.....Finland.