Banner Ad 1

Collision. Former Russian Submariner's comments, thoughts.

This is the place to read all about submarines in the real world!

Collision. Former Russian Submariner's comments, thoughts.

Postby U-5075 » Wed Jan 10, 2007 8:28 pm

MOSCOW, January 10 (RIA Novosti) - Poor sonar conditions might have contributed to a collision between a U.S. nuclear-powered submarine and a Japanese tanker in the Arabian Sea, a Russian naval expert said Wednesday.

The USS Newport News fast-attack submarine collided Monday night with the Japanese oil tanker Mogamigawa near the Strait of Hormuz, which separates Iran from the United Arab Emirates.

Both vessels suffered minor damage but no injuries, fuel spills or radiation were reported.

"The crew of the Newport News most probably fell victim to poor sonar conditions in the area," Gennady Illarionov, a former submariner, said in an exclusive interview with RIA Novosti.

"The sonar operator apparently did not hear the noise produced by the Japanese tanker, because it is fairly quiet," the expert said. "It [the tanker] has a propulsion plant located at the stern, and the collision occurred in the middle of the hull, about 200 meters (650 feet) from the rear of the ship."

"Such occurrences are rather frequent, because at a depth of 40 meters (130 feet) in poor weather there are strong wind waves that interfere with the acoustic field and could prevent a sonar operator from hearing the noise of a nearby target," Illarionov said.

He said the captain of the U.S. submarine was most likely to blame for the collision, because it occurred while the submarine was surfacing and the Japanese vessel was simply maintaining its course in the narrow strait.

"Surfacing is one of the most complicated maneuvers for submariners, especially from a depth of 40 meters to the surface," Illarionov said. "It is the most dangerous stretch, and that is when the two vessels collided."

The expert also said that 40 meters is a fixed depth in preparation for surfacing. At that depth, a collision is impossible and it allows a sonar operator to scan the acoustic horizon before reporting to the captain, who subsequently makes a decision to surface.

Following the captain's orders, the crew raises the vessel to periscope depth, and the captain is supposed to visually scan the horizon and make sure it is clear before finally surfacing.

Illarionov said the captain should have received the sonar operator's report before making the decision to surface. Otherwise, it would have been a violation of strict procedures.

In addition, the expert said, the Newport News, a Los Angeles class nuclear submarine, is vulnerable to sea collisions because of the design of its hull.

"These submarines have a single-hull structure," Illarionov said. "And any collision with another vessel can lead to serious consequences for them [the submarines]."

"I think the Americans were simply lucky because it was apparently not a direct hit," he said, adding that despite the 50-millimeter thickness of the hull, the impact should have left a deep dent in the super-hard steel.

The USS Newport News (SSN 750) has been operating as part of a U.S. Navy carrier strike group patrolling the Persian Gulf and nearby seas. It has a crew of 127.

Another Russian naval expert said Tuesday it was the captain of the submarine who was responsible for the collision.

"The incident involving the American submarine and the Japanese tanker in the Arabian Sea was due to intensive shipping in the region, which demands a high level of caution from captains of vessels, in particular from captains of nuclear submarines," the expert said.

"Most likely, the captain of the American vessel inadequately assessed the underwater and surface situation while the submarine was surfacing," he said.

The collision is not the first between a U.S. submarine and a Japanese vessel. In February 2001, a U.S. nuclear submarine, the Greenville, ran into and sank a Japanese fishing vessel near Hawaii, killing all nine people on board the Japanese boat.
U-5075
Registered User
 
Posts: 1134
Joined: Tue Feb 25, 2003 9:45 am

Postby expfcwintergreen » Wed Jan 10, 2007 9:05 pm

From "The Stupid Shall Be Punished"
http://bubbleheads.blogspot.com


USS Newport News Collision: The Ultimate Zoof ?

The Navy has apparently come up with an explanation for how the USS Newport News (SSN 750) hit the Japanese tanker M/V Mogamigawa that actually makes some sense and may spare the CO his career. From The Virginian Pilot:


The submarine Newport News was submerged and leaving the Persian Gulf when a mammoth Japanese oil tanker passed overhead at a high speed, creating a sucking effect that made the sub rise and hit the ship, the Navy said Tuesday.
That is the preliminary finding of Monday's collision between the Norfolk-based submarine and the Mogamigawa, a 1,100-foot-long merchant ship displacing 300,000 tons.
Both were southbound, crossing the busy and narrow Strait of Hormuz while heading into the Arabian Sea.
"As the ship passed over the sub, it ended up sucking the submarine into it," said Lt. Cmdr. Chris Loundermon, a spokesman for Submarine Force in Norfolk.
"It is a principle called the venturi effect," he said.
I'm sure they'll have to do some calculations to make sure this is plausible, but if the ship reported they weren't trying to come to PD, and assuming the ship control party didn't just randomly lose depth control at the worst possible time, this probably sounds as reasonable as anything else. There are lots of forces involved in operating a submerged submarine, and an upward force from the venturi effect is one submariners don't practice a lot in the dive trainer. (My old boat once popped to the surface because we hit a patch of colder water due to hitting the boundary where a river was discharging into open ocean, but that's another story...)

Assuming this explanation is true, the question now becomes: will the CO and crew be exonerated? The Sub Force has already shown that uncharted seamounts aren't a justification, and they do always warn you about the dangers of being "zoofed" -- submarine slang for having a surface ship pass directly over your position. The reason I always learned was that you didn't want to have someone above you in case you had to emergency blow, but it could be that there's a warning about the Venturi Effect buried in some tech manual. If there is, the CO is probably sunk. If this truly is a "first time we've thought of it" thing, though, the CO and crew might be fine -- unless, of course, all the "helpful" squadron, group, and force types who pour onboard a boat after an incident find anything that shows the Newport News wasn't operating completely in accordance with approved procedures...

In any event, the sub is apparently heading back to Bahrain for an inspection. If the boat really was sucked up into the tanker's stern, and if the tanker's propellers got ahold of the sonar sphere, we could see some interesting pictures.

Staying at PD...
expfcwintergreen
 

Postby U-5075 » Thu Jan 11, 2007 1:42 pm

Chris,

I like your explanation. There is a similar Venturi effect that happened 7 AUG 92 with the QEII when she was passing at a high rate of speed near Cuttyhunk Is. in the SW Cape Cod, Massachusetts area. But in this case the QEII was sucked down about 4.5 to 8 feet because of her high speed and her closeness to the bottom. The pilot had figured a 2 foot "squat" because he mainly piloted slower commercial vessels. The pilot also had changed the initial, intended course and had not conferred with the captain about this. And there was also this one, uncharted rock...........

http://www.ntsb.gov/Recs/letters/1993/M93_30_33.pdf
U-5075
Registered User
 
Posts: 1134
Joined: Tue Feb 25, 2003 9:45 am

Postby expfcwintergreen » Thu Jan 11, 2007 8:58 pm

I wish I could take credit for it, but the whole post is from Joel at TSSBP. There is a bunch of commentary from others who would know about this.

Nice story about Cuttyhunk, I've got a few similar "uncharted rock" stories, mainly in Boston Harbor..... :shock:
expfcwintergreen
 

Postby U-5075 » Mon Jan 15, 2007 12:16 pm

From a former person in the tanker industry.

"The surface effect is well known. Another problem that may have some bearing is the difficulty under certain conditions to detect these large tankers with passive sonar. The bulk of the ship masks machinery and propeller noise. I know from my working days in the tanker industry that we used to pass along VLCC routing to some sub operating authorities" ................... "so they could alert their boats."
U-5075
Registered User
 
Posts: 1134
Joined: Tue Feb 25, 2003 9:45 am

Postby Pirate » Tue Jan 16, 2007 12:22 am

I once tipped over in my rubber dingy. That was known as the drunken-partier effect.

I hate it when that happens.

Pete
HOLD FAST
User avatar
Pirate
SubCommittee Member
 
Posts: 795
Joined: Wed Oct 19, 2005 1:38 am
Location: Fort Wayne, Indiana


Return to Subs in the News

Who is online

Users browsing this forum: No registered users