T-Craft

[nikezz]

Originally Posted by BMcF

The answers to your questions are, in fact, intuitive and easily gleaned from the internet if you know anything about LOTS and amphib ops. That said:

1. The detractors and skeptics had a range of criticisms, many quite valid. They ranged from 'too expensive to affford enough of them' to being picky about potential CONOPS ("250 nm OTH ops?..are they crazy?") to being very legitimately concerned about the reliability and maintainability of such a complex machine, etc etc. You can even step it up a level and find strategists that question the future need for amphibious lift at all..


I read those, but since they looked like rants in the comments section, I didn't care since most wanted to just dump the project and buy more missiles without any proper analysis. I couldn't find any actual proper detailed analysis in the pros and cons of a T-craft.

2. No, you are not correct in saying that at all..but you are forgiven because you probably do no understand ONR's core mission. ONR is tasked with doing things, often very technically risky things, in the Science and Technology realm that regular Navy and its contractors dare not touch. T-craft may still 'transition' from the ONR world to the real world and it is even more likely that technologies developed over the course of the T-craft program will transition. And that right there is exactly what ONR is all about.

Ah, the ONR is very high risk, but the boss of the ONR didn't like a high risk project (T-craft), so it got canned?

3. Quite familiar with the Zubr's..have been for many years. The T-craft is not one..not even close. The T-craft is a long range self-deployable surface-effect-ship (SES) medium-capacity lighter that can, if needed, become a fully amphibious ACV for low-speed near-shore amphibious operations. Zubr is a conventional hovercraft.

Hmmm... From what I see, the Zubr looks pretty good as well. Is there a need for a T-craft when a Zubr would do almost everything except have a range of 2500 nm? Simple might be best.

[BMcF]

Originally Posted by kach22i

Back to Atlas just for a second.

John Carter's photos:
http://www.hoverclubofamerica.org/fo...pic=2063&st=15

Back to T-Craft:
A large SES mothership (Harrier's and helio's on roof) with six or so LCAC sized hovercraft below might be a nice alternate.[/quote]

That concept was in the initial mix of ideas some years back..it even had a nickname: 'Hens and chicks'. But the idea brought the yawns it deserved; it buys nothing in terms of new or improved capabilities.

[BMcF]

Originally Posted by nikezz

Hmmm... From what I see, the Zubr looks pretty good as well. Is there a need for a T-craft when a Zubr would do almost everything except have a range of 2500 nm? Simple might be best.

It was exactly that self-deployable long-range capability that formed a very key requirement for the T-craft requirements matrix. No hovercraft can possibly have endurance...and have you any idea how incredibly short-lived hovercraft skirt systems are?

[nikezz]

Thank you for that info on hover skirt maintenance. I see that everything negative about the T-craft, translates into costs.

Are there possible solutions to make the T-craft cheaper? For example, I saw you posted something on a 100% composite hull by Umoe which would make it lighter and I'm assuming able to take the same load.

[BMcF]

Originally Posted by nikezz

Thank you for that info on hover skirt maintenance. I see that everything negative about the T-craft, translates into costs.

Are there possible solutions to make the T-craft cheaper? For example, I saw you posted something on a 100% composite hull by Umoe which would make it lighter and I'm assuming able to take the same load.

The costs for T-craft were not so much the hulls..and that is usually true for most all smaller advanced craft. The costs were in the complex propulsion packages (water-borne mode and ACV mode..lots of turbines, gearboxes, diesel engines..etc) and the transformation systems that converted the craft from an SES in to an ACV.

The Umoe design was 100% composite (although with a titanium keel structure for beach landings) because composite is the only kind of hull design and materials Umoe uses for all their ships construction. The Textron design was aluminum hulled I believe..not sure about Alion's but would assume it was aluminum too, or certainly mostly so.

The lighter/stronger debate is always ongoing as it relates to aluminum versus composite. Outside the US, composite construction is winning that debate through demonstrated performance. The biggest Achilles heel with aluminum is the huge disparity between advertised parent material strength ...and the really lousy allowable stresses you end up with after factoring in fatigue and as-welded condition. With composites, as with titanium too actually, fatigue strength and as-welded strength are not factors you have to contend with.

[nikezz]

Originally Posted by BMcF

The costs for T-craft were not so much the hulls..and that is usually true for most all smaller advanced craft. The costs were in the complex propulsion packages (water-borne mode and ACV mode..lots of turbines, gearboxes, diesel engines..etc) and the transformation systems that converted the craft from an SES in to an ACV.

The Umoe design was 100% composite (although with a titanium keel structure for beach landings) because composite is the only kind of hull design and materials Umoe uses for all their ships construction. The Textron design was aluminum hulled I believe..not sure about Alion's but would assume it was aluminum too, or certainly mostly so.

The lighter/stronger debate is always ongoing as it relates to aluminum versus composite. Outside the US, composite construction is winning that debate through demonstrated performance. The biggest Achilles heel with aluminum is the huge disparity between advertised parent material strength ...and the really lousy allowable stresses you end up with after factoring in fatigue and as-welded condition. With composites, as with titanium too actually, fatigue strength and as-welded strength are not factors you have to contend with.

I'm assuming that steel was rubbed out due to the weight, rather than fatigue and as welded strength, since it has a high fatigue limit.

For aluminium, isn't there high tensile aluminium like AH 36/DH 36 to mitigate those problems?

Once again, I note that I am a newbie at this and may post some ridiculously obvious questions.

[kach22i]

Alcoa Joins Forces with Textron
http://finance.yahoo.com/news/Alcoa-....html?x=0&.v=1

Textron Marine & Land Systems, an operating unit of Textron Systems, a subsidiary of Textron Inc. (NYSE: TXT - News), in a smart move added Alcoa Defense, a business unit of Alcoa Inc. (NYSE: AA - News) to its Ship-to-Shore Connector (SSC) program bidding team. Textron along with its partner in SSC team, L-3 Communications Inc. (NYSE: LLL - News) is actively competing for the Navy’s Ship-to-Shore Connector (SSC) program.

The SSC program, estimated by the Navy to have a value of $4 billion, facilitates the construction of up to 80 hovercrafts to replace the aging Landing Craft Air Cushion (LCAC) fleet, starting in 2019. The LCAC is a class of air-cushion vehicle (hovercraft) used as landing craft by the U.S. Navy and the Japan Maritime Self-Defense Force (JMSDF). They transport weapons systems, equipment, cargo and personnel of the assault elements of the Marine Air/Ground Task Force both from ship to shore and across the beach.

Textron’s new partner for the bid, Alcoa Defense, is a premier player in designing, developing and manufacturing high-performance aluminum structures optimized for cost and weight. Alcoa’s expertise in aluminum production and design, proven design capability and advanced product manufacturing know-how will come in good stead for the construction of the hovercraft, which will have more than 100,000 lbs of aluminum each.

Alcoa Defense partners with industry leaders to design systems and materials that increase the speed, reach, agility and survivability of strategic platforms. Through an unmatched combination of defense and commercial engineering, Alcoa delivers multi-product, lightweight and cost-effective solutions for programs ranging from the F35 Joint Strike Fighter to the M777 Howitzer to armored tactical and fighting vehicles.

Headquartered in New York City, L-3 Communications is a prime contractor for C3ISR (Command, Control, Communications, Intelligence, Surveillance and Reconnaissance) systems, aircraft modernization and maintenance, and government services. L-3 is also a leading provider of a broad range of electronic systems used on military and commercial platforms.

Textron Marine & Land Systems specializes in the design, production and support of advanced marine craft, armored combat vehicles, turrets and related subsystems. Textron Marine & Land Systems serve military and commercial customers domestically and internationally, and have products operating in more than 35 countries.

Textron Systems manufactures unmanned aircraft systems, advanced marine craft, armored vehicles, intelligent battlefield and surveillance systems, intelligence software solutions, precision smart weapons, piston engines, test and training systems, and total life cycle sustainment services. Textron Systems includes AAI Corporation, Lycoming Engines, Overwatch, Textron Defense Systems and Textron Marine & Land Systems.

Textron Inc. has a global network of aircraft, defense, industrial and finance businesses that provide customers with innovative solutions and services. Textron is known around the world for its powerful brands such as Bell Helicopter, Cessna Aircraft Company, Jacobsen, Kautex, Lycoming, E-Z-GO, Greenlee, and Textron Systems.

Textron currently retains a Zacks #3 Rank (Hold). We also maintain a long-term Neutral rating on the stock.

Textron’s future success in the competitive defense industry depends upon its ability to develop and market its defense-related products and services to the U.S. government, as well as its ability to provide people, technologies, facilities, equipment and financial capacity needed to deliver those products and services at maximum efficiency.

They don't call any projects the JMACC any more?

[kach22i]

I'm not sure that I've posted all of these links and articles yet. Sorry if some are double posts.

Marines: From Procurement Tragedy to Triumph
May 11, 2010
http://newwars.wordpress.com/2010/05...dy-to-triumph/

Enter the T-Craft. Textron’s version is 253 feet long and carries a 250-350-ton payload – an M1 tank company or an entire Patriot battery. In long-range mode, as a waterjet-powered catamaran, it can ferry itself empty over 2500 miles of open ocean. Backing up to the stern of the ro-ro, it activates its air-cushion fans and uses a sophisticated three-dimensional positioning system to maintain station on the ship, which deploys a stern ramp so that vehicles can load.

It's A Hovercraft! It's A Catamaran! But Wait...
http://www.aviationweek.com/aw/blogs...7-f38665cdb571



http://www.foils.org/mtgpapers.htm

Phase II of the program—technology development, detail design, and modeling and simulation—is currently underway with three contractor teams: Alion, Textron, and Umoe Mandal. Following a downselect in May 2010, Phase III—prototype construction, demonstration, and testing—will extend to 2014.