tractor VS pusher comparison

So here is the comparison table of all my current pusher en puller propellers. All previous tests on the brushless AX-2210N RC motor with diffent propeller sizes on a 3 cell battery. I would like to test some 12 inch props and a 9x6 but I don't have these props at the moment.

(lower is better, e.g. red line is most efficient)

(this image was updated on 29/12/13: added the 9x6 prop benchmark)

As you can see the red line gives the best overall performance. The 11 inch prop is the most efficient. 

The difference between  a pusher prop and puller prop from the same size is clearly noticeable. But it is not enough to convert a standard quad with motors on top of the arms to a quad with motor underneath the arms. With the 9 inch prop you will gain  5% of efficiency when mounting your motors upside down. But to achieve this you need bigger landing gears. This adds weight to your quad and cancels out the benefit of the gained thrust efficiency.

Mounting 11 inch prop instead of 9 inch props will also give me 8% more efficiency. But because it's not really safe to oversize the prop I currently don't take the risk. The motor will always run warm and  lifetime will be shorter.

(this image was updated on 29/12/13: added the 9x6 prop benchmark)