I think this is one that might technically be level, but it doesn't look like it. I can see why the screener has commented CW
needed. Visually, it does look like it leans to the left. A little CW
will help to balance it I feel. Did you use the roofline of the building in the background as reference? That is perfectly level, but the verticals on the building still suggest it needs a little CW
and the aircraft does look a little unlevel. Maybe 0.15 or 0.25 degrees CW
and you should be sorted.
Equipment: 2x Canon EOS 50D; Sigma 10-20 EX DC HSM, 50-500 EX APO DG, Canon 24-105 f/4 L, Speedlite 430EX