Impacts of meteoroids and space debris on pressure vessels can have detrimental consequences for any mission. Depending on the parameters of the impacting particle and the characteristic of the vessel, the damages can range from relatively uncritical craters in the vessel’s surface to the catastrophic bursting of vessels, which besides the loss of vessel may result in severe secondary damages to surrounding components. In order to investigate failure mechanisms of thin-walled aluminum pressure vessels under hypervelocity impact of space debris, a non-powder two-stage light gas gun was used to launch Al-sphere projectiles impacting on unshielded and shielded vessels. Damage patterns and mechanisms leading to catastrophic rupture are discussed. Experimental results indicate that the impact kinetic energy of the projectile and the gas pressure in the vessel have an important effect on the damage modes of the vessel. On the one hand, high pressure gas can lead to a vessel blast. On the other hand, high pressure gas can mitigate the impact of the debris cloud on the rear wall of the vessel. Catastrophic rupture of unshielded gas-filled vessels can be avoided when the impact energy is less than a certain limit value. When the bumper is perforated, damage of shielded pressure vessel might be fatal for vessels with high gas pressure.