[SOLVED] Noctura U9S fan arrow directions are contradictory?

[fidesachates]

So I admit I've read a number of posts / articles / tips on how to tell your fan's direction. People's wording about when it "curves downward" or "bends left" are confusing to me. The most helpful advice I've seen is to look for printed arrows and on that one I'm a bit confused.

Below is my picture of a Noctura U9S. You can see the arrows are pointing towards the camera so I took that to mean the air flow was flowing, again, towards the camera. I don't believe that's correct now. When I did the tissue test, it seemed to be flowing in the opposite direction. This morning, I found arrows on the side of the fan that indicate the direction the fins spin and the airflow; the airflow arrow pointed in the correct direction (away from the camera). This is also inline with what I read about this model that the fan should be blowing air towards the heatsink.

My question:
What are the arrows in my picture indicating? It really confused the heck out of me and I installed the fan in the wrong spot because of it (fixed now).

 

[rubix_1011]

Looking at this fan, blade rotation is counter-clockwise (blades rotate to the left). The small arrows you are looking at are not directional arrows, but rather more likely a form of a NACA duct: https://en.wikipedia.org/wiki/NACA_duct

They are meant to channel airflow without excessive turbulence.

The directional arrows should be found on the outside of the fan frame, not the interior:

 

[fidesachates]

The small arrows you are looking at are not directional arrows, but rather more likely a form of a NACA duct: https://en.wikipedia.org/wiki/NACA_duct

They are meant to channel airflow without excessive turbulence.

Cool thanks! This is what I was looking for.