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    Re: Eight (or Nine) Mile Chart Error!
    From: Frank Reed
    Date: 2013 Jan 25, 11:41 -0800

    David Fleming, you wrote:
    "What is the process for checking the charts?"

    Well, you run a ship around at high speed until you hit something! :) That is how the submarine USS San Francisco discovered a poorly charted seamount back in 2005 which amazingly enough, considering the devastating damage, did not sink the sub: http://en.wikipedia.org/wiki/USS_San_Francisco_(SSN-711). Deep underwater features are notoriously difficult to chart. Of course, a reef like this one in the Philippines is visible in satellite imagery.

    You asked:
    "Why was that not already done before the grounding?
    Why is it not an ongoing task?"

    I'm sure it is. The catch is money. How much money do you spend on quality control of well-validated data? The obvious answer here is "a little more," but when do you stop? The DNC has been under development for 25 years or more, and I know from personal conversations that it went through years and years of quality control before it was counted as operational. Does anyone know how long it has been an operational product?

    One article states:
    " According to an NGA memo sent to the Navy on Jan. 18, the error was in the coastal DNC, apparently in use on board the Guardian at the time of the grounding. The general DNC and hardcopy charts show the reef’s location correctly, NGA said."

    That strikes me as something that could have been assessed in automation and maybe that's what has been completed in the past week. They said they also found a similar case off the coast of Chile.

    Finally, why wasn't the reef detected by other means? According to news articles, they ran aground at 2:25 am, and the weather was rough with five foot seas. An observer on deck might possibly have been able to detect the reef visually, but it doesn't sound like it would have been easy.

    -FER

    PS: "79 crew members were taken off the ship on Jan. 18, 45 transferring to the Navy survey ship BOWDITCH..." Ha! Bowditch saves the day.


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