I’ve been following the drama of the stranded Russian mini-sub. One of the main problems is that they have limited oxygen, which doesn’t give the rescue team much time to retrieve the sub. This got me thinking and I came up with a simple idea that could make all submarines safer: Every submarine should have an external valve hookup so that pressurized air can be pumped into the cabin from an external source. This valve design should be a universal standard that every navy and coast guard agrees on, so that all submarine rescue teams have compatible equipment for it. When a submarine is stranded on the sea floor, the first thing rescuers would do is to send down a remotely piloted drone with an air supply line. The drone would locate the external air valve and attach the air supply line to it. Once attached, a rescue ship on the surface would begin pumping appropriately pressurized air into the submarine’s cabin, which would relieve the time pressure caused by dwindling native oxygen supplies in the submarine. This air supply valve could also house a wireline communications hookup for two way communications between surface teams and the submarine crew.