How much flatulence would it take to become airborne?

More than the average human could muster all at once. I suppose you could try to contain all that noxious methane into a balloon, over a period of time perhaps, and then try your hand at levitation.

Your anus, ass and bowels would disintegrate if you had a fart big enough to give you lift.

Unless you were talking about a making a baloon.

amazing question! Since the cows are being blamed for global warming because of their methane production and none of them are floating away, I am not too worried about it happening.

MATH!

Going with a human weighing 150 pounds, the fart would need to produce over that many pounds of force per second, so going with 200 pounds of force (just a nice round number), and the goal of, say, 5 seconds, you’d need to be able to generate 1000 pounds of force.

The good news is that, based on the circumference of the, er, “outlet valve”, you wouldn’t need to carry 1000 pounds worth of gas. You’d just have to calculate the PSI and go from there. That I’d have to leave to someone smarter than I am.

Superman’s ability to fly, explained?

There’s a straight dope about this.

My “flatulence” always tends to lift me from my chair.

@Haleth I actually saw it there too. I thought it would be amusing here. Thanks.

Here’s a way to reduce the amount of flatulence required to lift 150 pounds as explained by @RocketSquid. We use Craig Venter’s approach and create yet another strain of synthetic bacteria which was optimized to metabolize methane and convert it to hydrogen (using some other stuff in our guts to provide the energy for this endothermic chemical reaction).

Then we send @zenele across the Atlantic, apply extra care during the landing procedure to avoid any Hindenburg-style disaster asking all smokers to extinguish their cigarettes before the fart actually materializes thereby bringing him down to the ground safely.