Wednesday, February 18, 2009

That Ship is So Fraked!

A few things to keep in mind:

This is a shot of the USS Spruance in drydock. Ticonderoga-class cruisers were pretty much built on the same hull form. The big bulge at the bottom of the bow is the sonar dome. On a Tico, the bottom of the dome is 33' underwater.



This is a sonar dome for a SQS-53 sonar. A rubber window, which is a very large radial rubber belt, goes in the gap. The metal base underneath is known as the "banjo." Those black squares are transducer elements.


This is one of the screws from an Arleigh Burke class DDG. The Burke class uses the same engine as the Ticos, the LM-2500 gas turbine, so odds are the screws look about the same. ("Screws" are what you might call "props.")

Look closely at the base of the blades and you can see that they can be rotated. Unlike steam turbines, gas turbines cannot be reversed (the LM-2500 is, at the core, a jet engine from a jumbo jet), so if you want to back up, you have to twist the blades. Indeed, from 0-12 knots or so, the turbines rotate at the same speed; so at slow speeds, the ship's speed is controlled by the pitch of the screws. When the ship goes faster than that, the turbines speed up and the pitch stays the same.

The Port Royal went aground in 22 feet of water. A Tico cruiser has a displacement of over 9,000 tons. Take 9,000 tons of ship, run it into hard ground that is 11 feet shallower than the depth of water that the ship draws and Bad Things are going to happen.

Really bad things.

This is the aft vertical launcher for a Tico cruiser. Under each of those doors is a silo for a SM-2/3 ER missile. The missiles are just a skosh over 26 feet long.

If you were to twist the hull a lot, as you might in a grounding, you could twist the launcher doors out of true. That is a Bad Thing.

Last night, I posted that "officials" said that the screws were damaged and that the tips were"'sheared off." Those blades, as you can see, are one-piece right down to the hubs.

What I am told is this:

The blades for the screws were not damaged, they were destroyed. The screw blades were sheared off. The shafts were bent enough that the shaft bearing, which probably are large babbit-bearings, were damaged. The stern tube seals were damaged and the ship was taking on water into the shaft alleys. The base of the rudders were also grounded, driving the rudders up or twisting them. The reduction gears (between the gas turbines and the screw shaft) may have been damaged. One or more of the gas turbine engines might have been damaged. I don't know if there is a shear coupling in the power train between the gas turbines and the shaft; there could be, but it would have to be a huge-ass thing., so I tend to doubt it.

As you might imagine, the sonar dome was toast. The banjo was bent up, the transducer itself is probably badly damaged.

The twisting of the hull reportedly damaged at least one of the vertical rocket launchers and cracked the firemain system. A number of bulkheads throughout the ship were twisted and buckled. A number of fuel tanks leaked, though apparently not into the sea. Hull members (I-beams welded to hull plating) are likely twisted, cracked and/or buckled.

The firemain system is composed of piping that is pressurized with seawater; it is used for cooling as well as fire-fighting. When a ship runs around, the firemain can get clogged with bottom debris. The firemain on the Port Royal supposedly is clogged with sand and coral debris. Coral and sand are extremely abrasive, so the firemain pump(s) that were online at the time of the grounding probably will need to be torn down. The valves throughout the firemain may all need to be checked and the piping itself will have to be flushed.

Seawater is also used for cooling. The air-conditioning units on the ship (there are several large units) use seawater for cooling and those are probably all clogged with sand and coral. There is a lot of other damage to the ship that in other circumstances would be a serious "oh, shit," but now are almost minor in comparison.

The Port Royal was in her first day of sea trials after spending two months in drydock. She will be back in drydock for a very long time. The damage doesn't stop there, as the long-range scheduling committments for the ship will have to be filled by other ships, which will find their deployments extended and/or moved up. Maintenance work on other ships will be deferred or delayed, both because the Port Royal is occupying a drydock and because the work will suck up dollars already allocated. Given the amount of work that may be required to fix her up, it's not beyond the realm of possibility that the Navy may decide to patch her up for now to make sure she doesn't sink, decommission her, refloat her, store her along a pier and fix her up later once money and resources are identified. (That's what the Navy did when the USS Belknap burned in the 1970s.)

And, of course, a number of the officers of the Port Royal had better start thinking of what they are going to do next, as their careers are over.

Sunday, February 15, 2009

The Best Brain Surgeon in the Colonial Fleet

John Hodgman.



He was called upon to remove a bullet from the brain of Sam Anders in the episode "No Exit," which aired in the US on February 13, 2009.

Wednesday, February 11, 2009

Ruminations on the Post-Coup Colonials

I suppose it may seem ooky to some that I am thinking about this. After all, the world of Battlestar Galactica is a goddamn TV series. The show, however, has dealt with some very adult and contemporary themes. The most cutting-edge were the episodes set on New Caprica, which dealt with the year-long occupation by the Cylons and the resistance of the Colonials. There were examples of pre-emptive imprisonment and torture for interrogation used by the Cylons and their Colonial collaborators. The Colonial resistance used spying, assassination and suicide bombings. At times it seemed as though those topics were covered better by the show in 2006 than they were by the press and the pundits when those topics applied to Afghanistan, Israel and Iraq.

I would not have been surprised if the attempted coup by Zarek and Gaeta had been used as a way to terminate the show early, that the "ten episodes" of Season 4.5 turned out to be a deception. That would probably have been too dark for the show's writers.

Admiral Adama is now back in command of his ship and in command of a crew, a good number of whom he cannot trust. The Fleet is divided between ships that would have followed Zarek and ships that remained loyal to President Roslin. Eleven of the twelve members of the Quorum of Twelve, the legislature of the Colonial Fleet, were killed on Zarek's orders, only the representative of the survivors of Caprica, Lee Adama, remains alive. Zarek and Gaeda were summarily shot by a firing squad commanded by the Admiral.

There is no effective representative government left. Roslin now has basically a dictatorship; Zarek's objective was achieved, but his enemies got the benefit of it. Roslin and the Admiral could easily sink into a fair degree of paranoia, creating secret police from known loyalists and imprisoning known or suspected traitors.

They are also on the verge of running out of fuel and supplies. They took nothing from Earth, the planet was too radioactive. Since they restocked on their fuel "Tylium" in the first season, there has been no mention of further supplies, so they have to be running low now. There is also the rest of the Cylon fleet to contend with; the rebel Cylons of Twos, D'Anna (the one surviving Three), Sixes and Eights are apparently down to one battered BaseStar.

The Colonial Fleet is, in the old aviation saying, running out of altitude, airspeed and ideas at the same time.

Six episodes to go.

Sunday, February 8, 2009

Battlestar Galactica- "Blood on the Scales"

I thought the rebellion would end with either Starbuck putting a bullet in Felix Gaeta's head or shoving him out an airlock and Tom Zarek fleeing the Fleet.

I was wrong, of course on both counts. But not by much for Gaeta. Once Gaeta aligned himself with Zarek, their fates were tied to each other. The rebel forces fell surprisingly fast. Once word spreads around the Fleet that Zarek had the Quorum of Twelve shot, his memory will be cursed forever.

And you just know that Admiral Adama had to have taken no small pleasure in personally commanding the firing squad that shot both Gaeta and Zarek.

Monday, February 2, 2009

The Oath

In this episode, Tom Zarek and Felix Gaeta trigger a bloody uprising on the Galactia. We don't get to see very much of the fighting, but as Apollo and Starbuck make their way around the ship, we see a shitload of expended rifle cartridge cases.

First off, I have to love Starbuck. When it comes to fighting, she is one cool woman. Apollo had been captured by a group of rebels; when she ordered them at gunpoint to release him and they refused, she shot two of them them and then said: "I can do this all day."

(Those pistols don't seem to have much killing power for the ball round. I don't know what they are, but they definately aren't .45s. [Edited to add: They appear to be FN Five-seveNs.])

Gaeta's forces took Admiral Adama and Col. Tigh; who overpowered their guards and escaped. As the episode ends, it appears that Adama and Tigh are going to go all "Butch Cassidy" against a large group of Colonial Marines.

I don't see the uprising ending quickly, but I am reasonably sure that it will end with Tom Zarek fleeing in a ship or a small group of ships. Felix Gaeta will probably wind up with Starbuck either putting a bullet in his head or shoving him out an airlock.

Still, in my opinion, the best hour of TV during any given week.