Originally Posted by
pattern_is_full
It is the vortex generator fin on the engine nacelle. Given the very-low-slung 737 engines (remember they are so low they have to be flat on the bottom for ground clearance!) that fin is about 2.5m/8 feet above the ground.
Yeah, no, that fin is nowhere near 2.5 meters above ground. More like 1.8 meters...