How do you get a plastic bottle to crush itself on an airplane?

Question

Do you do it as the plane's landing or taking off? And does it have to be empty, full, or semi-full? And I think the cap also has to be on...?

:P I know it's the pressure change, but I've forgotten how to do it.

Answer 1

The bottle would beed to be emptied, and capped at cruising altitude. Upon landing, if the differential is great enough, you'll have a flattened bottle. The reason is that most aircraft only pressurize to 5000 feet. If the bottle were emptied in flight, and capped, the air pressure in the bottle is that of the aircraft at cruising altitude. When the aircraft lands, the cabin pressure will rise, and that is why the bottle gets flattened.

Answer 2

drop it from cruising altitude, it should crush nicely.

I don't think its possible, because a soda can is already slightly pressurized unopened, so it won't really do anything as it climbs or descends. If it was open and you could somehow seal it at altitude, it might crush when the plane descends, you could try putting the can upside down in a cup of water, but you would have to hold it there until you land.

Answer 3

Open an empty soda bottle at cruising altitude. Due to pressurization, the equivalent outside altitude will be about 1/7 of that amount; for example, at 35,000 feet the cabin's pressurized to 5,000 feet. (Once I took a mountaineering altimeter aboard a plane to find out.)

So, if you seal the bottle with low pressure air and return down to low altitude, say sea level, then there will be a force compressing the bottle and it'll crinkle a bit — but not too much, I'd guess.

The best test would be to seal a bottle at the highest point of a high-altitude flight (I've been as high as 55,000 feet trans-Pacific), then going to sea level. Say, the Auckland from Los Angeles flight. That would result in the greatest change, since the pressure inside would be the smallest.