The inventive subject matter is generally directed to a pack with an automatically opening compartment. The pack has a body that defines a volume for the containment of articles, and a strap system for supporting the pack in a user's body. A section of the pack is hingeably coupled to another body portion of the pack. The hingeable section has a first condition, providing an opening to a compartment in the pack, and a second condition, closing the opening to the compartment. The hingeable section is coupled to a spring system that is (1) unloaded when the hingeable section is in the first condition and (2) relatively loaded when in the second condition, so that the compartment automatically opens when the closure system is released. The pack may include a closure system for locking the hingeable section in the closed condition.