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Thread: USS America (LHA-6) News

  1. #61
    Military Professional dundonrl's Avatar
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    Quote Originally Posted by 85 gt kid View Post
    How come the Marine ships are so much slower then say Destroyers or Super Carriers? I looked up the specs for LM2500 GTs and theyre about 40 ft long in theyre container. Now if they used a LM6000 they could have almost double the power with roughly 56 ft in legnth for the unit. I know it's a little longer but the increase in speed to ??? would be nice .

    BTW sorry for the random question .

    carriers have to be fast, because they need to make "wind" over their flight deck to safely launch aircraft.. destroyers have to be fast, to keep up with the carriers (done it once, and DAMN did my ship, the Momsen) use A LOT of fuel cause the carrier (Abraham Lincoln) was constantly doing 30+ knots to launch her birds).. we were plane guard, not a desirable position for a DDG, that's for sure..

    Amphibs don't need that speed to launch AV-8B's, and normal speed when transiting the ocean is about 14 knots for any navy warship.

  2. #62
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    From Team Ships Public Affairs
    PASCAGOULA, Miss. (NNS) -- The Navy accepted delivery of the future USS America (LHA 6) from Huntington Ingalls Industries April 10.

    America, the lead ship of the class, is the first of the Navy's next generation amphibious assault ships which replaces the aging Tarawa class. Delivery marks the official turnover of custody of the ship from the shipbuilder to the U.S. Navy.

    "This is a great Navy and Marine Corps day," said Capt. Christopher Mercer, Amphibious Warfare program manager for the Program Executive Office, Ships. "This ship's delivery will bring significant new capability in both amphibious assault and aviation support, while enhancing forward presence around the world."

    America completed sea trials in February, with no major deficiencies identified. Following delivery, the commissioning crew will move aboard and begin shipboard training in preparation for ship sail away. The ship's commissioning is slated for late 2014 in San Francisco.

    The ship will provide forward presence and power projection throughout the world as an integral part of joint, interagency and multinational maritime expeditionary forces. Her addition to the fleet brings not only added amphibious capabilities, but also further aviation capabilities as she will be able to handle current and future aircraft such as the tilt-rotor MV-22 and the Joint Strike Fighter.

    LHA 6 uses the same zonal electrical distribution, electric auxiliary systems, and auxiliary propulsion system as the USS Makin Island (LHD 8), resulting in lower fuel, maintenance and lifecycle costs. By using these proven systems, the U.S. Navy is avoiding design and development costs often associated with a first in class ship.

    America is the first ship of the Amphibious Assault Replacement Program, LHA(R). The LHA 6 design removes the traditional well deck to include space for an enlarged hangar deck, expanded aviation maintenance facilities, and an increase in available stowage for parts, support equipment and aviation fuel. America spans an expansive 844 feet, displaces an impressive 44,971 long tons and can operate at speeds of over 20 knots.

    As one of the Defense Department's largest acquisition organizations, PEO Ships is responsible for executing the development and procurement of all destroyers, amphibious ships, special mission and support ships, and special warfare craft. Delivering high-quality war fighting assets - while balancing affordability and capability - is key to supporting the Navy's Maritime Strategy and the future of U.S. Maritime strength.

  3. #63
    Senior Contributor surfgun's Avatar
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    Posted: July 8, 2014 3:00 PM

    Amphibious Assault Ship America To Sail For Commissioning

    PASCAGOULA, Miss. — The amphibious assault ship America (LHA 6) will sail away from Ingalls Shipbuilding in Pascagoula on July 10, destined for the West Coast and its Oct. 11 commissioning ceremony in San Francisco, Huntington Ingalls said in a July 8 release.

  4. #64
    Defense ProfessionalSenior Contributor tbm3fan's Avatar
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    At first I wondered why they were commissioning the ship in San Francisco which no longer has any naval base. Then it hit me that is the typical time for Fleet Week out here and sure enough it is. October 11th is a Saturday and in the past the Fleet sails in on Saturday morning. If that still is the routine, as the web site says check back, I will be out there to get some pictures from above Fort Point. Also Blue Angles are back. Hurrah, and tough to all those who claim the noise scares their pet dog

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    I noticed that the max speed of the America class is around 22 knots, a couple knots slower than Wasp.

    Was there some sort of trade-off made that resulted in the lower speed? And why do these classes of ships (LHD/LHAs) tend to have max speeds in the lower end of the 20 knot range? Other major ships seem to be able to get up to 28-32 knots. I would think that you'd always want to get the Marines to their destination as fast as possible.

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    Quote Originally Posted by tmasi View Post
    I noticed that the max speed of the America class is around 22 knots, a couple knots slower than Wasp.

    Was there some sort of trade-off made that resulted in the lower speed? And why do these classes of ships (LHD/LHAs) tend to have max speeds in the lower end of the 20 knot range? Other major ships seem to be able to get up to 28-32 knots. I would think that you'd always want to get the Marines to their destination as fast as possible.
    More speed= bigger engines= more fuel= less fuel left to supply the embarked marines with= reduced capabilities.

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    Quote Originally Posted by tmasi View Post
    I would think that you'd always want to get the Marines to their destination as fast as possible.
    From what I witnessed, that would have either been the gym or the chow line.
    "We are all special cases." - Camus

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    Quote Originally Posted by tmasi View Post
    I noticed that the max speed of the America class is around 22 knots, a couple knots slower than Wasp.

    Was there some sort of trade-off made that resulted in the lower speed? And why do these classes of ships (LHD/LHAs) tend to have max speeds in the lower end of the 20 knot range? Other major ships seem to be able to get up to 28-32 knots. I would think that you'd always want to get the Marines to their destination as fast as possible.
    It's the difference between tactical speed and strategic speed. The engineering plants in the LHA/LHD class ships, dating all the way back to the original USS Tarawa (LHA 1), are optimized for providing a remarkably good strategic speed for the size of ship in question while also allowing for long loiter time on station. 20 to 22 knots is more than enough to get where the Marines need to be, especially if the ship can do it all day long without breathing hard. That's better than 500 nautical miles per day, over 600 statute miles if one prefers. That's nothing to sneeze at.

    Basically the CONOPS for an amphibious group that includes LHA/LHD class ships is to get the CVSG into the area first, at Warp Factor Eight, to "prepare the battle space"; MILSPEAK for kicking the freaking door in. While they are doing that, the bus drivers will be bringing the Victory Verification Units (VVU - aka "Marine: Mark 1, Mod 0, 1 Each") into the theater.

    The timing of things like that is practiced more often than one might think, although not always together. Regardless, once the assault begins, the CVSG will position itself between the amphibious group and the lines of advance from the sea to the beach where they will pull double duty both protecting the beach head from attack from the sea, as well as doing mostly deep interdiction operations. Marine organic air will do most, but not necessarily all of the CAS for troops on the beach. It's important that the shepherds (CVN, CG, DDG) protecting the flock near the beach be able to haul ass to get where they need to be fight off the wolves. That's why they can do better than 30 knots; i.e. "tactical speed."

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    How well can a CVN's escorts keep up when it decides to haul ass across the pacific? I know Burkes can do 30+ knots, but I'm assuming they can't do 30+ knots from San Diego to Perth without topping off their fuel tanks at some point.

    On that note, how fast can ships drive while being refueled at sea? I'm trying to imagine a fleet oiler refueling a destroyer at 20+ knots. That has to be a pretty tall order.

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    Quote Originally Posted by SteveDaPirate View Post
    How well can a CVN's escorts keep up when it decides to haul ass across the pacific? I know Burkes can do 30+ knots, but I'm assuming they can't do 30+ knots from San Diego to Perth without topping off their fuel tanks at some point.

    On that note, how fast can ships drive while being refueled at sea? I'm trying to imagine a fleet oiler refueling a destroyer at 20+ knots. That has to be a pretty tall order.
    Are you sure you're not some spy masquerading in here???
    That seems to be some questions a lot of adversarial navies would like to know the answers to!

    Do you think it is some mistake that the newest commanding officer of one of the newest US warships is named "Kirk"???
    "Captain, should we engage warp drive?"
    Last edited by SlaterDoc; 09 Jul 14, at 16:34.

  11. #71
    Senior Contributor SteveDaPirate's Avatar
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    I don't want anyone to violate opsec (on an open forum no less). As a Kansas boy I am generally so ignorant of Navy matters that I'm afraid I don't know what things would be considered sensitive to ask about. Please forgive my faux pas.
    Last edited by SteveDaPirate; 09 Jul 14, at 16:56.

  12. #72
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    Quote Originally Posted by SteveDaPirate View Post
    How well can a CVN's escorts keep up when it decides to haul ass across the pacific? I know Burkes can do 30+ knots, but I'm assuming they can't do 30+ knots from San Diego to Perth without topping off their fuel tanks at some point.

    On that note, how fast can ships drive while being refueled at sea? I'm trying to imagine a fleet oiler refueling a destroyer at 20+ knots. That has to be a pretty tall order.
    Quote Originally Posted by SlaterDoc View Post
    Are you sure you're not some spy masquerading in here???
    That seems to be some questions a lot of adversarial navies would like to know the answers to!

    Do you think it is some mistake that the newest commanding officer of one of the newest US warships is named "Kirk"???
    "Captain, should we engage warp drive?"
    Quote Originally Posted by SteveDaPirate View Post
    I don't want anyone to violate opsec (on an open forum no less). As a Kansas boy I am generally so ignorant of Navy matters that I'm afraid I don't know what things would be considered sensitive to ask about. Please forgive my faux pas.
    I appreciate both the Doc's circumspect point of view, and Steve's question that prompted it. It's not a classified matter with regard to how these things are done. One way, and probably the best way to get a maximum speed of advance, with both a CVN and escorts is to have the CVN serve as the strike group's "oiler du jour." My term, but if you can grasp the point, that there is a whole lot of JP-5 aboard that CVN which, when not flying airplanes, can be used to refuel its escorts, then you start to see the beauty of the system. We used to do this even aboard Constellation, and she was conventionally powered.

    The nice thing about the LM2500 main propulsion engines (four of them; a marinized version of the engine originally found on the L1011 air liner) and Allison 501-K17 SSGTGs (three of them; a marinized version of the same engine found on C-130s, etc.) that provide electrical power to our CGs and DDGs, is that they will just about burn mule piss if that's all you got. Back in the day, the ships used Diesel Fuel Marine to power them, with JP-5 as a backup. I burned both DFM and JP-5 in my boilers if I needed too. They also were very forgiving with regard to what you fed them. Now days, it is my understanding that the fleet almost exclusively burns JP-5 as it sort of makes the logistics problem for the supply guys easier.

    A safe UNREP speed is 14 to 16 knots. You can top those small boys off pretty quickly as the JP-5 transfer pumps in those CVNs can really push the GPM as fast as the receiving ship can take it. The CGs are sea water compensated systems, and the DDGs may be too, but frankly, I don't really know; never having served or inspected one (even though a steam guy, when I was a member of the CINCPACFLT Propulsion Examining Board, I did the Spruance, OHP, and Ticonderoga-class propulsion plant inspections on occasion, looking at their waste heat boilers, distilling plants, and diesels [in the OHPs] and other auxiliary systems not directly propulsion related). What that means is that as fuel is burned, sea water via the ship's fire main system enters the storage tanks automatically. This maintains the ship's stability in all conditions. In fact, if you were to actually empty those tanks at sea (not that you could, as there is no practical way of doing so), the ship would be danger of capsizing. There is a thing that looks remarkably like the float in your toilet tank, the kind that rides up and down on a column. The float has a specific gravity that allows it to ride on the interface between the sea water and the fuel in the tank. The reason why I am spelling all of this out, is that these systems are highly automated and when far out at sea, you can really push the fuel transfer pump pressure and flow rate because the tank level system enables near real time readings that preclude oil spills, etc. In fact, US Navy warships rarely refuel in port these days because of EPA regulations, etc. Far better to do it far out at sea where accidents are rare because of the level of attention to detail that a good Oil King and his or her assistants bring to the table while underway.

    Anyway, I'm sure a CVN could top off a CG in an hour or less. No problem. The reason why you don't do more than 16 knots is that you get into some interesting hydraulic phenomena, not the least of which is a wicked Bernouli effect between the hulls of the two ships. See, in cross section, the underwater portions of the hulls of the respective ships for all the world resemble a convergent-divergent or "DeLaval" nozzle. Too much water moving too fast between the two ships can actually suck them together. So, you slow down a bit and get the job done before kicking it in the ass again.

    Another way to refuel along the track is to have several fleet oilers loitering along the intended course. Sadly, in my view, the one ship that used to be the saving grace of a fast moving CVSG was the Sacramento-class AOE. Big, beautiful, and FAST, FAST, FAST!!! They had the main engines originally destined for the last two Iowa-class BBs that were cancelled before the end of WWII married with some beastly 600PSI D-Type boilers with automatic combustion control systems that didn't exist when the BBs were originally built.They could do well over 30 knots and do it all day long. People have heard me talk of them before, but I just can't emphasize enough what fantastic ships they were. They were the brainchild of Arleigh Burke himself; a guy who knew a little bit about going places in a hurry.

    Anyway, those are a few of the ways to denude that particular feline. Keep those cards and letters coming. If you haven't figured out by now, I love talking about the practical aspects of operations at sea. No two days are ever alike.

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    Quote Originally Posted by desertswo View Post
    Another way to refuel along the track is to have several fleet oilers loitering along the intended course. Sadly, in my view, the one ship that used to be the saving grace of a fast moving CVSG was the Sacramento-class AOE. Big, beautiful, and FAST, FAST, FAST!!! They had the main engines originally destined for the last two Iowa-class BBs that were cancelled before the end of WWII married with some beastly 600PSI D-Type boilers with automatic combustion control systems that didn't exist when the BBs were originally built.They could do well over 30 knots and do it all day long. People have heard me talk of them before, but I just can't emphasize enough what fantastic ships they were. They were the brainchild of Arleigh Burke himself; a guy who knew a little bit about going places in a hurry.
    Since you mentioned the Sacramento class, in your opinion, how do the Supply class AOE's compare to the Sacramento class? Are they as good and fast with the LM2500's instead of the BB powerplants? What do you think about Rainier and Bridge being mothballed over the next year at such a young age? It's a shame the USN junked the Sacramento class so quick, I've long suspected it was to purge itself of those battleship engines to further their case to discard the Iowa and Wisconsin by eliminiating the ongoing knowledge of those plants.

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    Quote Originally Posted by ChrisV71 View Post
    Since you mentioned the Sacramento class, in your opinion, how do the Supply class AOE's compare to the Sacramento class? Are they as good and fast with the LM2500's instead of the BB powerplants? What do you think about Rainier and Bridge being mothballed over the next year at such a young age? It's a shame the USN junked the Sacramento class so quick, I've long suspected it was to purge itself of those battleship engines to further their case to discard the Iowa and Wisconsin by eliminiating the ongoing knowledge of those plants.
    I understand that the Supply-class are pretty fine ships as well, but while fast, they aren't as fast as the Sacramentos were.

    As regards their mothballing, I believe there are many things happening to our military right now that will bite us all in the ass in the not too distant future. This is just one more.

    As regards eliminating the Sacramentos as a sort of oblique way of "attacking" Iowa and Wisconsin, one shouldn't get too far ahead of the story regarding those engines. It was just the engines, and no other part of the BBs' engineering plants that made their way into the AOE-1s. HP-LP Turbine and reduction gear set technology hadn't changed in form or function since WWII. What did change was boiler technology, and that changed quite a bit, and had nothing to do with the BBs.

    I think the bigger issue overall was eliminating non-nuclear steam ships to the greatest extent possible, because the Navy also wanted to eliminate much of the training infrastructure that used to exist in support of an all steam fleet. People, and the training of them, is always the long pole in the tent, and if they could mostly eliminate an entire class of engineering ratings, and the training infrastructure that goes with, then mores the better. For instance, there used to be Machinist's Mates and Boiler Technicians. Now there are only Machinist's Mates, and some of them carry the NEC for the maintenance and operation of boilers. Soon, there won't even be those except the ones who operate the engineering plants on the CVNs. We were dinosaurs, and since there was no way for us to adapt, we died. It's that simple.

  15. #75
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    zraver and desertswo, thanks for taking the time to answer and providing all the interesting detail. It makes whole a lot of sense when seen in that light.

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