- destroyer
USS Fitzgerald (8,900 long tons "full", 154m) now
berthed at the US 7th Fleet Naval
- Philippine registered container
ship ACX Crystal (39,565 tonnes deadwight, 222m) now berthed at
Tokyo’s Oi wharf.
The
bodies of a number of US sailors were found, once water was pumped out (at Yokosuka) from the 2 crushed and flooded compartments of USS Fitzgerald.
Japanese authorities were
looking into the possibility of "endangerment of traffic caused by
professional negligence", Japanese media reported, but it was not clear
whether that might apply to either or both of the vessels.
It is most likely USS Fitzgerald's "Captain" Commander Bryce Benson, in hospital, is already being questioned along with relevant officers and crew who were on Fitzgerald's bridge.
It is not clear:
- how dark or foggy the conditions were? OR
- if Fitzgerald was suffering relevant equipment, especially radar and AIS [1], technical
breakdowns?
breakdowns?
[1] AIS is the automatic
identification system (part reliant on satellites) used for collision avoidance on
ships. Very likely AIS was on both ships - but was it turned off on Fitzgerald for "hide Fitzgerald" exercise conditions?
PHOTO: USS Fitzgerald struck on the starboard side above and
below the waterline. (Photo courtesy Reuters: Toru Hanai via
the BBC)
---
Map courtesy
MarineTraffic, news agencies including BBC
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Pete
Hard to believe that with today's radar and AIS, a 7000 ton destroyer can still collide with a 29000 ton container ship. The Burke should have given way and pass to the stern of the cargo ship. Not the USB best demonstration of seamanship. If we cannot even see a massive very noisy ship, silent submarines need not fear.
ReplyDeleteKQN
Hi Pete
ReplyDeleteMy condolences to the victims, their families and friends.
The accident was occurred one of the most crowded sea area in Japan [1]. Relatively weak armor of Aegis seems to increase its damage [2]. There are some issues on investigation by Japan Coast Guard (JCG) [3].
[1]http://www.iza.ne.jp/kiji/events/news/170617/evt17061722050018-n1.html?utm_source=yahoo%20news%20feed&utm_medium=referral&utm_campaign=related_link
Following the accident, on Jun 17, Mr. Aikira Sanbai, Deputy Director of the 3rd Regional Coast Guard Headquarters of JCG explained "In the waters where the accident happened, about 400 vessels sail a day on average."
According to the JCG, the route toward Ise Bay direction from Tokyo Bay through Irozaki where accident occured was a sea area where the ship traffic volume is high next toTokyo Bay, and is called often "quasi-congested waters".
[2]https://headlines.yahoo.co.jp/hl?a=20170618-00000040-san-pol
Mr. Tadasu Kumagai, a former SDF officer and military critic, said, "Although radar is air-defensive and has the ability to detect distant objects, detection of ships nearby is not much different from fishing boats." Aegis system does not operate during normal voyage, you usually have to rely on the crew's eye observation in addition to the navigational radar.
Mr Kumagai said, "Aegis is excellent as an advanced system to protect others. But, its armor is thin, it will dent as soon as it hits." According to military officials, there is also an intention to secure maneuverability by thinning the armor.
[3]http://www.iza.ne.jp/kiji/events/news/170617/evt17061721580017-n1.html?utm_source=yahoo%20news%20feed&utm_medium=referral&utm_campaign=related_link
The accident of the Aegis and container ship seems to have occurred in the territorial waters of Japan. Although the JCG has the right to investigate, a high hurdle of Japan-US territory agreement stands out. In addition, high-performance Aegis ships are top secret (executive in the Ministry of Defense). There is a high possibility that the US military will not cooperate with the investigation, and it is unclear how far the cause investigation will proceed.
Regards
Hi Pete
ReplyDeleteCommander, U.S. 7th Fleet, Vice Adm. Joseph Aucoin said the damage was so serious and the Aegis nearly sank [1].
Key points of the investigation were shown in reference [2].
[1]https://theconservativetreehouse.com/2017/06/18/7th-fleet-vice-admiral-joseph-aucoin-press-conference-collision-at-sea-of-uss-fitzgerald/
USS FITZGERALD experienced extensive damage and flooding after a collision with the Filipino container ship at 0220 local time, 17 June, approx. 56 nm off the coast of Honshu, Japan.
The damage included a significant impact under the ship’s pilothouse on the starboard side and a large puncture below the ship’s waterline, opening the hull to the sea.
[2] https://headlines.yahoo.co.jp/hl?a=20170618-00000059-asahi-soci
It is believed that the Philippine flagged container cargo ship collided from the right rear of the Aegis ship. However, which one was obliged to avoid the collision depends on whether the two-ship's course before the collision, the speed, and the guard were sufficient.
The cargo ship crew testimony that "the two vessels were moving in the same direction" is also a clue. The Maritime Collision Prevention Law stipulates that overtaking ship should not obstruct the opponent's ship until they are far enough away
Regards
Ships of this type and smaller dont have 'armour' for external hull in the usual sense of the word.
ReplyDeleteMerchant ship hull plates are also available in different strengths to suit the stresses calculated by modern ship design software, going thicker isnt necessarily best.
https://flatsteel.arcelormittalsa.com/fspcatalogue/DataSheets/UnCoated/Web_datasheet_a3.5.pdf
Naval ships requirements for surface vessels where stronger strength steel is required can look at high strenth steels used for submarine hulls eg HY80 which is used in some parts of the hull for Burke class destroyers. see this reference which discuused damage to the USS Cole. Carrier decks would have similar or greater strength- details likely classified.
http://navy-matters.blogspot.co.nz/2012/06/ship-construction-and-naval-armor.html
In lots of cases the HS steel is for ballistic protection / airbursts etc and not collisions. Another special case would be those ships transiting ice bound areas and even higher strengths for icebreakers ( which generally ride up on pack ice and use their weight to break it)
AIS is used to assist navigation and identification of other ships and navigation marks and as this reference states, should 'never be used for collision avoidance' ( which is different to the airliner system ACAS)
ReplyDeletehttp://www.marineinsight.com/marine-navigation/automatic-identification-system-ais-integrating-and-identifying-marine-communication-channels/
A very good overview of AIS as well.
I am very shocked to hear that the US navy sources say the Fitzgerald 'nearly sunk'. The original design should be able to maintain stability with the sort of limited damage that occurred. They have some serious problems with a very large class of ships if the flooding extended much past the hull compartments directly affected.
USS Fitzgerald was the 12th ship of the class , commissioned over 20 years ago in 1995, depending if its had a major overhaul may not go back into service, especially since its the electronics which date the quickest.
This New York Post aricle of June 19, 2017 is interesting. Title "Tears — and questions — on the ramming of USS Fitzgerald"
ReplyDeleteat http://nypost.com/2017/06/19/tears-and-question-on-the-ramming-of-uss-fitzgerald/ :
eg.
"- Presumably the freighter was equipped with a transponder, and should have been squawking its position, speed and other relevant data automatically; Fitzgerald should have been reading and processing the information, also automatically, and making command decisions accordingly.
- The old war-movie images of radar watch-standers staring at a tiny cathode-ray tube’s fuzzy images is almost are obsolete as wooden hulls.
...On the surface ships, there are repeaters on the bridge.
A catastrophic radar failure instantly would’ve been apparent on the monitors because all contacts (vessels large and small, aircraft and radar return from surface clutter) would’ve been lost. All those repeaters would basically go blank — and someone, somewhere, would notice.
Beyond radar, US warships fairly bristle with detection devices that perform across virtually all visual and electronic spectra. And heaven only knows what information is routinely beamed to warships from satellites and other observation platforms.
So it’s very difficult to imagine how a leviathan like ACX Crystal cargo even got close to Fitzgerald — to say nothing of actually ramming her...."
With AIS class A (like on this cargo ship) or class B (for recreational vessels like I am used to), in combination with the appropriate chart plotter and navigation SW, you can set CPA (closest point of approach) and TCPA (time to closest point of approach) alarms so you know if you are on a collision course and when with a target depending on its speed, and take appropriate action like calling on VHF to the target ship. I am sure a container ship will have its AIS broadcasted while warships normally do not (I have a gun, you do not mentality). A beauty of AIS is it works around islands while radars do not.
ReplyDeleteOn a warship, there will always be plenty of hands on deck besides the OOD and watch. Besides, there are eyes and hands in the CIC as well. The CO and all those officers' careers are basically finished given the 7 fatalities.
KQN
A probably Japanese Anonymous has indicated:
ReplyDelete"It was found that the Aegis ship seemed to have had an obligation to avoid by the Aegis warship in the accident that the Aegis ship of the US Navy and a container ship collided at the offshore of Shizuoka prefecture.
http://www.news24.jp/articles/2017/06/19/07364657.html "
Looking at http://www.news24.jp/articles/2017/06/19/07364657.html (in Japanese) the article seems to say - the Japanese Coast Guard is of the view that USS Fitzgerald had an obligation to avoid the container ship - particularly given the paths of these "crossing" vessels.
The hit is on the starboard side of the destroyer so there is no doubt that the container ship has the right of way.
ReplyDeleteIt is not a surprise that some compartments on the destroyer were breached and flooded when hit, likely by the bulbous bow. A bulbous bow is in all cases made from steel plates that are several inches thick. That thing will be a perfect ram just as those Spartan warships centuries ago.
KQN
The container ship, due to its much larger size, also had a right of way on a less formal level.
ReplyDeleteA warship would also be expected to have many more crew (than the container ship) at their posts on eyeball-watch and sensor-watch.
I think only if there were circumstances like the container ship:
- had no navigation lights on, OR
- it was moving way over the speed limit
could the container ship be blamed.
Even if the container ship was speeding (not saying it was), its max speed is between 20-25 knts depending on design. Most seem to max out around 22 knts. The destroyer has a max speed of 30+ knts & a sprint speed of 35+ kns (actual sprint speed unknown but for reference Australia's Anzac class is 40+ knts). Sprint speed (when you realy wind up the turbine) can only be sustained for a relativley short time. So unless the nav lights were not on, or there was heavy fog or rain, the destroyer should have easily avoided the container ship. They were not in a naval task force or anything where warships have to operate close to each other. The area is known for its heavy shipping, so they should have had plenty of eyes on the job. If the container ships nav lights were not working in such an area they would have been leaning on the fog horn & talking on the radio. I assume that US Navy ships do routinely listen to civilian frequencies?
ReplyDelete