Keeping the blogosphere posted on the goings on of the world of submarines since late 2004... and mocking and belittling general foolishness wherever it may be found. Idaho's first and foremost submarine blog. (If you don't like something on this blog, please E-mail me; don't call me at home.)

Saturday, January 22, 2005

Origin of the "Discolored Water"

Much has been made about the notation on the chart that USS San Francisco was using during her grounding last week that had been marked "discolored water". This area was apparently charted 3 miles south of where the San Francisco collided with the undersea mountain. This article on the Navy Times website shows the actual satellite photograph that, in retrospect, may have shown the seamount, and could have been used to update the chart. An important thing to remember is that the "discolored water" notation was not based on the satellite evidence; it was based on a single report from the Japanese from the 1960s or earlier. The potential misplotting of the discolored water is probably therefore not due to incompetence, as the Navy Times article seems to be trying to imply. Rather, it is probably more likely due to navigational accuracies available in the 1960s, before GPS. Probably some Japanese surface ship had noted discolored water, and conscientiously reported it to their authorities along with their best estimate of their position when they saw it. Hopefully the San Francisco grounding will act as a spur for the cognizant authorities to investigate these reported anomalies that litter the charts and determine once and for all if they're accurate.

Going deep...

Update 2144 22 Jan: Here's the New York Times' take on the same story. (Will probably require registration soon.) Excerpt:

"David Sandwell, a geophysics professor at the Scripps Institution of Oceanography in San Diego, said it was also possible that the danger zone - an oval area described as containing "discolored water" - was a mistaken and poorly located reference to the undersea mountain.
"Defense Department officials have said that the notation dated to the early 1960's, and that it probably came from a surface ship that had spotted murky water. The discoloration could have been a temporary problem, like an oil slick, or a hazy indication of an undersea structure...

"The exact location of the crash remains classified. But the undersea mountain shows up on the satellite images at 7 degrees, 45.1 minutes north latitude and 147 degrees, 12.6 minutes east longitude...
"Besides relying on charts, submarines also receive fixes from navigation satellites and take soundings of water depths. According to officials, the San Francisco's officers have said they took a sounding just four minutes before the crash, and it indicated that the vessel was still in 6,000 feet of water."

This one piece of new information, that the ship took a sounding four minutes before the collision, will be very important in possibly exonerating the Captain and crew of any dereliction, if the sounding was properly evaluated (i.e. verified to match the expected water depth shown on the chart).

Update 0727 25 Jan: Here's another copy of the story above, from The Seattle Times, that probably doesn't require registration.

11 Comments:

Blogger Andy said...

I was under the impression that we usually prefered to use standard transit or shipping lanes when making a routine transit.

One would think that common transit routes between let's say Guam-Australia, or Guam-Yokosuka, Guam-San Diego, Guam-S.Korea would have (should have) been thoroughly surveyed long ago.

1/22/2005 6:43 PM

 
Blogger Bubblehead said...

Maybe there were waterspace management concerns that necessitated them to go outside of the normal lanes. Still, if the seamount is narrow enough, we may be dealing with the "big ocean, little ship" effect, where even a well-travelled route may not have had a fathometer-equipped ship go over that precise spot. I know I always preferred to travel outside the normal travel lanes -- made it a lot easier to come up to periscope depth!

1/22/2005 7:15 PM

 
Blogger Andy said...

i just had a flash back to my first trip to the Med, we needed to come to PD on the mid watch and there's surface contacts *everywhere*. I was in ESM and we're clearing baffles and doing tma legs for like 30 farking minutes 'cause sonar's picking up new contacts everytime we turn. And just when we think we got 'em figured out there's more hairy contacts: on the right drawing left for instance.

So anyways, this on the Sculpin where the fire control system was designed in the 50's, it's all syncro's - the Mk 101 FCS and we can only track one or two contacts at a time. I had to go out and man the geo plot and help out just to get a good idea of where everyone is...and this is just trying to go to PD for a Sattelite fix and radio traffic.

So anyways, it's been almost an hour now, the CO had been out there for a while monitoring and advising and we finally get all contacts on the right drawing right, on the left drawing left and it's obvious we're never going to get the minimum distance we were trying for so we just went up anyways.

That was in the fist week after arriving in the Med. What a blast it is to operate a sub in the Med, there are so many countries exposed there, so much traffic, lots of radar activity for ESM, i can't believe they paid me go on those trips.

1/22/2005 11:25 PM

 
Anonymous Anonymous said...

The flashback for me is USS Alabama SSBN 731 in 1985 during PSA after commissioning. Did some ops out of Groton for a few days very routine stuff. Standard ESM watch for me, our friends with the DON/DON2's weren't there. Pulled into the old NUSC pier across the river from EB. After we're tied to the pier and everything is secured the Navigator and I go topside through the forward hatch. I look up at the forward end of the sail and it looks like a checkerboard. We picked up a fishnet somewhere along the way. The net was no longer there but you could see the pattern and a long steel cable mark. Probably a gill net or some ghost floating free.

If it doesn't make noise and you don't already know it's there, then it's kind of hard to avoid!

1/23/2005 8:00 PM

 
Anonymous Anonymous said...

Ok, Shipping lanes......how many people think shipping lanes exist between guam and austrailia? Has any body even looked at the possible routes to get there? You have to get through alot just for the most direct route.
The pacific is just so darn massive. I remember going through places were the best chart to use was questionable. There is just alot of the ocean floor that is uncharted and to top it off it is still shifting and changing. Can you imagine how much the ocean floor has changed after the Tsunami and earthquake in the indian ocean? Ok I am done venting.

Sea story:
My last boat was a trident out of Bangor Wa. Any submariner that has been in and out of Bangor can tell you, we have some intresting interactions with the wildlife.
We had a issue with the MBT vents inport due to a Sealion breaking a fitting.
One morning the CO is coming aboard and sees another Sealion on his boat. So the CO decides he wants to "shoo" this one away. So he goes aft to show this Sealion who is boss. This Sealion is a male and weighs about 400lbs, The CO....about 170-180lbs (you do the math). The CO goes over the life line and starts to "shoo" away the Sealion. The Sealion just sits there as the CO gets closer. The Sealion finaly recognizes that this man is coming towards him. The Sealion raises his head as if to say "are you serious?" The CO is still getting closer and waving his arms. Finaly the Sealion has had enough, He starts barking and charges the CO. The CO, being a very smart man, turns and runs back to the life line. The Sealion goes back to suning himself. Nature 1, Mankind 0.

1/24/2005 5:38 AM

 
Blogger Bubblehead said...

I never had to deal with the sealions myself (I always operated out of San Diego and Groton) but I remember giving training on one "lessons learned" message that came out of Bangor. Without getting too technical, seems a Trident in-port had a big change in draft (bow goes down something like 6 inches in an hour) during the midwatch, so they call the newly-qualified duty officer up. He decides that since they had quite a few sealions sitting on the stern earlier, and now they're gone, that's caused the change in draft, so no reason to worry -- he goes back to the rack. Duty Chief finds out about this when he comes up for his 0200 tour, and the message didn't specify what happened next, but I assume the DCPO gave the Duty Officer a lesson in the forces required to change a ship's draft noticeably. (It was actually a leaking tophat on a MBT vent.)

1/24/2005 6:25 AM

 
Anonymous Anonymous said...

LOL, yes that was us.

1/24/2005 11:40 AM

 
Anonymous Anonymous said...

Sea lions affecting the trim of a Trident? Come on!

Every TRUE Submariner knows the only animals with enough girth to effectively organize a trim party are GOATS.

“Chief of the watch – watch our bubble.”

1/24/2005 10:53 PM

 
Anonymous Anonymous said...

You are 100% correct. You can pack the aft end of the sub with sealions and the draft WILL NOT change. But when one of the sealions flippers wraps around a hose to the MBT vents and pulls hard enough to break the fitting is a diffrent story. The Watch standers topside reported the draft change to the CDO but not the Duty Chief. Of course when the broken fitting was discovered the next morning by the Agang Chief, the Topside watch and CDO were quickly disqualed due to poor watchstanding.

1/25/2005 2:11 PM

 
Anonymous Anonymous said...

You are 100% correct. You can pack the aft end of the sub with sealions and the draft WILL NOT change. But when one of the sealions flippers wraps around a hose to the MBT vents and pulls hard enough to break the fitting is a diffrent story. The Watch standers topside reported the draft change to the CDO but not the Duty Chief. Of course when the broken fitting was discovered the next morning by the Agang Chief, the Topside watch and CDO were quickly disqualed due to poor watchstanding.

1/25/2005 2:11 PM

 
Blogger Bubblehead said...

"Always tell the Duty Chief" was my motto; even when I thought I knew what I was doing as Duty Officer, I always got the Chief involved... saved my butt more than once.

1/28/2005 1:07 PM

 

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