Thoughts on the San Francisco Collision

There are a number of ways you can look at this NY Times story about the underwater collision of the US submarine San Francisco. The first and most easily accessible way into the story is the sheer empathy one has for the family of the seaman killed in the accident. While this is certainly a story of tremendous personal tragedy, it is also quite impressively not a story about national tragedy.

The messages said the submarine's hull was severely damaged after the head-on crash into what Navy officials believe was an undersea mountain that was not on the navigation charts. One message said the submarine, the San Francisco, was traveling at high speed, and the impact practically stopped it in its tracks and caused flooding in parts of the bow.

later in the article

Navy officials said the San Francisco was traveling at 30 knots when it careened off some part of the undersea mountain range. In one of the e-mail messages, Admiral Sullivan wrote that on impact, the vessel made a "nearly instantaneous deacceleration" to about 4 knots.

It goes without saying that you have to build any vessel that travels on water very well, and certainly submarines to an even higher standard. I do not know for sure, but I suspect that designing a structure that withstands a 30 knot crash with a mountain and one capable of withstanding the tremendous pressures of depth are not mutually exclusive. However, I don’t suspect there is anything even close to an airbag inside of a nuclear submarine (though I suspect some personnel may have had access to a seatbelt). With the help of a wonderful program, I know that 30 knots is equal to 34.5 miles per hour (34.52338mph if we wanted to get really precise). A head-on collision by a submarine traveling at nearly 35mph with “an undersea mountain” results in a submarine that can still float and the loss of only one life. I can only tip my hat to the incredible men and women who design and build submarines. You do amazing work.