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It might be the preserve of fantastical action movies, but we’ve probably all wondered at some point or other if it’s actually possible to fly through the air by firing bullets down at the ground.
Fortunately, you must wonder no longer, as Randall Munroe of XKCD has done the science for you. As he explains:
The principle here is pretty simple. If you fire a bullet forward, the recoil pushes you back. So if you fire downward, the recoil should push you up.
But can it be done? The short answer is, amazingly: yes. The longer answer is of course a little more involved, but amazingly interesting, combining guns with rocket science. For instance:
[O]ur optimal craft comprises a large number of AK-47s (a minimum of 25 but ideally at least 300) carrying 250 rounds of ammunition each. The largest versions of this craft could accelerate upward to vertical speeds approaching 100 metres per second, climbing over half a kilometre into the air.
And there is plenty, plenty more like that. Go read it. Now. [What If?]
Watch This Crazy Hercules Airplane Flying Just Five Metres Above the Ground
3D Printed Headphones You Can Build From the Ground Up
An Awesome Guy Made a Flying Drone Armed with a Paintball Gun
In all seriousness, I opened Gizmodo, saw an article about how many balloons it takes to fly a house, realised I hadn’t read this weeks What If? and went to read it. Then I came back to Gizmodo and it was suddenly the most recent story.
Freaky.
Technically, yes.
Rocket jumps are real? ID Software we’re really onto something!
Wasn’t there a concept for a giant spaceship that, due to its massive mass, could only take off by detonating nukes underneath itself? I think the biggest size they proposed was something like 8 million tonnes
http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)
It would appear from the link at the bottom of your post that yes, there was indeed a concept for a giant spaceship that due to its massive mass, could only take off by detonating nukes underneath itself
I am rather flabbergasted that they actually considered detonating enough nuclear weapons to propel something weighing 8million tons in the atmosphere though.
Was something like this not covered in Mythbusters recently. I think they classed it as “plausable” because the chances of it actually working succesfully was very slim. Plus if you strapped 25 or even 300 or a million Ak -47′s to a craft It would take some ammount of computer jiggery and shear luck to get them all to fire at the same time.
The same with the baloon and the hosue one. Mythbuster tryed this and failed it as well
Dur….
I thought everyone learned that from the A-Team movie.