Twice now I’ve carried a carbonated beverage aboard an aircraft here in SA. In each case, upon reaching cruise altitude, I attempted to open the plastic bottle. Not only could I not open them in the cabin, even having returned to the ground I was unable to do so. Pressing on the side of the bottle confirms that a substantial increase of pressure inside the bottle has occurred.
In one case I used a knife to pierce the cap to relive pressure. In another case I jammed the lid into a door jam to achieve sufficient grip to twist off the lid.
On a jetliner, cabin air altitude is somewhere between ~6,000′ to ~8,000′. As the altitude increases the air pressure surrounding the bottle drops. Thus, the air inside the bottle expands. The result, apparently, is sufficient internal air pressure such that one can’t unscrew the lid and the bottle feels like it could explode with even the slightest provocation. Physics-wise, perfectly logical.
But, the weird thing is that once back at ground level one still can’t open the bottle despite the fact that air pressure inside the bottle should have returned to a much lower pressure.
Did the lid simply get jammed on in a high pressure situation? Or, did something else happen? At altitude, as the bottle’s internal pressure decreases one would expect CO2 to be forced from solution