I'm not sure I do either. It's certainly one of their more absurdist comics.
It's likely a reference to the Shuttle Carrier Aircraft, with the Shuttle swapped out for a Falcon 9. This is strange, because the diameter of Falcon was sized to be small enough to still be transportable by road.
Clearly it’s the shuttle carrier but why is the rocket backwards, why is it screaming wheeee and why is the pilot unhappy about the situation? I’m usually pretty good at figuring out the intent behind a weird comic but this one has me stumped!