That’s the built in leaf blower to make sure that the runway is clear for autumn landings. Most airports have their own de-leafing crews, but not all of them.
They were mandated to be installed after a string of landing crashes in the 90s got people making “fall” jokes too often, which upset the FAA.
Huh…
Looks like that image specifically is from a fan-made version of Phase II, but yeah you’re spot-on.
https://trekmovie.com/2008/08/28/fanmade-new-phase-ii-enterprsie-ogam-announce-dvd/
I knew about Phase II, and that elements of it were merged into TMP and TNG, but I only remembered the triangular Enterprise concept that was later the basis of Discovery.
This all sent me down a rabbit hole where I learned things like Xon (originally a replacement for Spock) became Saavik, and Decker and Ilia were the basis for Riker and Troi.
Thanks!