This was recently posted on LinkedIn. Being a former submariner myself, I had to take notice. In 1982, we had a collision with a freighter on auto-pilot near the mouth of the Chesapeake. We don't have to worry too much about underwater mountains but there are poorly (un)charted obstacles out there.
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While submerged southeast of Guam in 2005, the USS San Francisco struck an uncharted undersea mountain at a depth of 525 feet while traveling at full speed. The collision heavily damaged the front of the submarine, crushing its sonar dome and ballast tanks, but the pressure hull stayed intact. One sailor, Joseph Allen Ashley, died from head injuries, and 97 others were hurt. The crew managed to surface the submarine and return it to Guam under its own power, despite the extent of the damage.
The investigation found that the navigation team had overlooked important data that could have revealed the seamount’s location. The failure to use available charts was blamed as a key cause. To bring the submarine back into service, its damaged bow was replaced with the forward section of the retired USS Honolulu. Repairs were completed by 2009. The incident became a serious lesson for the Navy on the importance of proper navigation checks and accurate seabed mapping.
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While submerged southeast of Guam in 2005, the USS San Francisco struck an uncharted undersea mountain at a depth of 525 feet while traveling at full speed. The collision heavily damaged the front of the submarine, crushing its sonar dome and ballast tanks, but the pressure hull stayed intact. One sailor, Joseph Allen Ashley, died from head injuries, and 97 others were hurt. The crew managed to surface the submarine and return it to Guam under its own power, despite the extent of the damage.
The investigation found that the navigation team had overlooked important data that could have revealed the seamount’s location. The failure to use available charts was blamed as a key cause. To bring the submarine back into service, its damaged bow was replaced with the forward section of the retired USS Honolulu. Repairs were completed by 2009. The incident became a serious lesson for the Navy on the importance of proper navigation checks and accurate seabed mapping.
