XKCD Isn't Funny - #1660 - Captain Speaking
When I was like six I overheard my dad telling a friend "...so the captain does all the flight stuff, but then he forgets to turn off the thing, so you just hear him say to the copilot 'Goddamn, Doug, what I could really use right now is a cup of coffee and a blowjob.' So of course the stewardess runs to the cockpit to be like 'guys, the things on', but before she can tell them the pilot asks her, kinda annoyed like, 'Hey - where's the coffee?'" And for ages I thought that was a true story and I told tons of my friends but NOPE. It's even on Snopes, albeit in a slightly different form.
Anyway, this comic's problem is that the captain is upfront about his failings and is kinda quasi-apologetic about it. A captain being unapologetically rude about his improper-ness is funny, and a guy trying to hide that he doesn't know how to fly a plane is funny, but this guy being all "geez, folks, gonna be honest i got no idea what i'm doing" is lacking in punch.
I think we'd also benefit from an interior plane view, kind of an establishing shot, before the captain makes his announcement. It'd bring us more into the 'plane' mindset and make the contrast between the regulated expectation we have for airplanes and the goofy pilot more pronounced. As it is, we don't even see the airplane first, the comic is very non-visual in its presentation, which makes it weaker.
Oh, Happy Easter, by the way!