Ya gotta see the video ... Biden's hustling up the carpeted staircase when he trips not once, not twice but three times. He's holding the railing with one arm but still goes down, and even appears to bang his shin.

Biden finally makes it to the top after a few stumbling blocks, and turns around for a salute before ducking inside AF1.

The Prez is on his way from Joint Base Andrews to Atlanta, where he's meeting with community leaders in the wake of the massage parlor shootings ... and he's already putting the trip in trip.

Unclear what caused him to eat it, but you'll remember Biden suffered a hairline fracture on his right foot in November, he wore a boot to help the injury, but maybe there's still some healing left to happen.

Biden's not the only Prez to take a spill on the steps of Air Force One though, Gerald Ford took a nasty fall in 1975 when the plane touched down in rainy conditions in Austria.

It's been a rough week for POTUS and Vice President Kamala Harris and their official planes ... Harris' Air Force Two had some mechanical issues and she had to get a new ride.