# B Air pressure on planes and leak-proof containers...

1. Jul 8, 2017

### nicoleyounger

On airplanes - do you know of a container or bag that will stops individual bottles with liquid from leaking/ exploding from the changes in air pressure?

2. Jul 8, 2017

### Asymptotic

The problem is that gas within the container expands as external air pressure decreases. If the container can't withstand the resulting forces it blows apart, or splits enough to allow internal pressure to match external pressure (and in the process creating a leak). One way to fight this is squeeze out as much air as possible from each container before packing them, or transfer the contents into smaller containers than can be fully filled.

Another is to put the containers prone to failure into a larger, heavy walled, and sealed container. I didn't track this down to see if this became a marketed product, but a pressure tight travel container intended for consumer use has been patented.

3. Jul 8, 2017

### nicoleyounger

This is really helpful especially the link to patent - thank you very much for taking the time to respond.

4. Jul 8, 2017

5. Jul 8, 2017

### Staff: Mentor

Probably not, but if you squeeze the air out of the containers before the flight, they won't pressurize.

6. Jul 8, 2017

### Asymptotic

Yep, a Google search for leak proof travel containers "high altitude".

7. Jul 8, 2017

Thanks

8. Jul 9, 2017

### sophiecentaur

It's a matter of how much energy is stored under Atmospheric Pressure. Both a liquid and a gas will 'pressurise' but because the volume change is so small, the stored energy is different in a liquid.
E = PΔv
Testing diving bottles is always done by pumping them full of water and seeing how much they expand. They can be pressurised with a couple of strokes of simple hand pump. If they burst or split with water in them they will just open up a bit and the pressure returns to ambient. When full of air, they were pressured by running the (~5kW) compressor for several minutes and all that energy comes out at once (a bomb).

9. Jul 9, 2017

### nicoleyounger

Thank you for taking the time to respond.

10. Jul 9, 2017

### nicoleyounger

Thanks for taking the time to respond.