Is the luggage/cargo compartment pressurized on ALL planes or just commericial passenger airplanes?

I had some old wine shipped by air, and they arrived with corks sticking out on several different occasions. Sometimes, there would also be a small amount of wine which seeped out of the bottle. I have inspected the corks and they are not rotten or faulty.





I believe this is the result of the pressure inside the bottle being substantially higher than the pressure outside, and this pressure forces the cork out along with some wine (if the package was on its side). Once the bottles are on the ground (where the pressure inside the bottle is the same as the outside) the wine no longer seeps out, even if I violently shake the bottle.





But in movies (like ';Transformer'; and ';Air Force One';) we see people walking around the luggage compartment of commerical passenger planes, implying that they are pressurized like the cabin.





My wine seeps and exhibits a protruding cork ONLY when shipped by air. I've never had this problem with bottles with Ground shipping.





Thanks for everyone's help!Is the luggage/cargo compartment pressurized on ALL planes or just commericial passenger airplanes?
Not ALL luggage compartments are pressurized, but even those that are pressurized only maintain pressure equivalent to about 8000 feet above sea level. Depending on where your wine is bottled, this could be enough pressure differential to push out some corks.





Perhaps you should look into a stronger seal for those bottles that will be shipped by air.Is the luggage/cargo compartment pressurized on ALL planes or just commericial passenger airplanes?
It's not that the airplanes are unpressurized, it's that the pressure changes in them during flight. Generally, if you flew from say, Florida to Kentucky, the bottles would start out at sea-level pressure inside and outside the bottles. When the plane climbs, the cabin pressure can reach up to 8,000', meaning the pressure inside the bottle is higher than the plane. This would force the corks out. When it lands, the pressure would be like 2,000' elevation, and there would still be pressure on the cork.





This problem is not limited to airplanes. If you took a bottle of win in the car from death valley to the top of the rockies, you would have the same problem.
that's one reason champagne makers wire the cork on..