Forum: General F-35 Forum

Failing at math now?

100k hp * 1.35 (a 35% increase) = 135k hp.

This means that the 22DDH has 35% more power than 16DDH.

What math are you using to get 12%?

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SpudmanWP wrote:

Failing at math now?

100k hp * 1.35 (a 35% increase) = 135k hp.

You have wrong numbers.

16DDH : ?? COGAG?? 2????100,000ps?
http://ja.wikipedia.org/wiki/%E3%81%B2% ... B%E8%89%A6

22DDH : ?? COGAG??,2????112,000ps?

http://ja.wikipedia.org/wiki/19500%E3%8 ... B%E8%89%A6

SpudmanWP wrote:

Failing at math now?

100k hp * 1.35 (a 35% increase) = 135k hp.

You have wrong numbers.

16DDH : 100,000ps
http://ja.wikipedia.org/wiki/%E3%81%B2% ... B%E8%89%A6

22DDH : 112,000ps

http://ja.wikipedia.org/wiki/19500%E3%8 ... B%E8%89%A6

Hy?ga class helicopter destroyer

http://en.wikipedia.org/wiki/Hy%C5%ABga ... _destroyer

"...Japan plans to build a new 22DDH helicopter carrier, which is larger than the Hy?ga class. The new 22DDH will replace the Shirane class helicopter destroyer, which was scheduled to be decommissioned in FY2014.[7][8]

Its been speculated that the Hy?ga class ships would be outfitted with VTOL/STOVL fixed-wing aircrafts, such as Harriers or F-35 Lightning II[9][10][11][1][12]...."

^ Yong-weon, Yu (2007-08-27). "After 40 Years, Japan Achieves Warship Dream". Columns (Chosun Ilbo). Archived from the original on 2008-04-23. http://web.archive.org/web/200804231037 ... 0007.html. Retrieved 2008-07-13.
^ Saunders, Stephen (editor) (2007). Jane's Fighting Ships Vol. 110, 2007-2008. Coulsdon: Jane’s Information Group. p. 401.
^ Minnick, Wendell. "Japan's New Ship: Destroyer or Carrier?' Defense News (Springfield, Virginia). June 30, 2008. p. 13.
^ Herman, Arthur (2007-09-09). "Pacific armadas: growing Far East navies mean new challenges for U.S.". Opinion (New York Post). http://www.nypost.com/seven/09092007/po ... tm?page=0. Retrieved 2008-07-13.
^ "????????????????". Asagumo News. 2009-08-27. http://www.asagumo-news.com/news/200908 ... 82703.htm. Retrieved 2009-09-07. (Japanese)
^ ????????????????, Ministry of Defense
_________________

Japan’s Latest Destroyers: Baby Flat-Tops? by Kyle Mizokami on Jul 1, 2011

http://newpacificinstitute.org/jsw/?p=7051

"...There was no problem to operate STOVL fighter jets with this capacity and, therefore, it was up to the JMSDF if they would like to use them as helicopter carriers or not.

At present, it is said that the JMSDF has no plan to use other aircraft besides helicopters on the Hyuga-class escort ships, but these ships can carry about twelve F-35B class airplanes, if the JMSDF wishes. There are four spots for taking-off and landing and a space between each spot is widely taken. Of course, it is a different issue whether this ship can load aircraft or properly operate them on this ship.

High-temperature exhaust would most likely become the biggest obstacle when a jet STOVL aircraft is landing and taking off the helicopter deck. If used only once or twice for emergency landings and taking-offs, there will be no major problems. However, the deck areas need to be thermally protected if steady operations are required. [THERMION] Japan has knowledge about the process of operation of STOVL ships, but is deficit in actual know-how.

Currently a new 22DDH is under construction. It is 19,500-ton class DDH with an estimated displacement of 24,000 tons, which is close to Hyuga; and its total ship length, 248 meters, is longer than Hyuga. Whatever the explanation of the JMSDF is, this ship actually is a “carrier” as Japan’s neighboring countries view it. According to the estimation of the JMSDF, the number of helicopters on board the carrier is said to be less than ten. The JMSDF might be estimating conservatively for operation and budget reasons...."

The problem is no official Japanese military sources has stated a requirement for V/STOVL fixed wing aircraft. From the same blog:

"[In reference to linked sources] Note however the distinct lack of official sources in the article, which should temper enthusiasms some."

"“Japanese accounts” tend to be from the military enthusiast magazines. These magazines are high quality production jobs, but they also tend to assume that Japan will get all of the latest and greatest American gear; they ran with the F-22 ball for years, putting the Hinomaru on Raptors until it was painfully obvious Japan was not going to be allowed to buy them."

"Admittedly the changes described–if real–point towards fixed wing aviation, but they also make good design sense, especially from a safety standpoint, and given the increase in overall ship size. That having been said, there’s no consensus that Japan needs carriers. Japan has no power projection ambitions that drive a need for carriers. For its strategic needs, Japan is the aircraft carrier.

It’s fun to imagine Japan having carriers again, but it just isn’t realistic."

http://newpacificinstitute.org/jsw/?p=1482

However, there are Chinese bloggers and state controlled media sources that claim the Japanese are planning for the F-35B version to equip these vessels, but that plays more for their domestic political need to question Japanese intentions rather than a reflection of future Japanese policy.

slowman2 wrote:

SpudmanWP wrote:

Failing at math now?

100k hp * 1.35 (a 35% increase) = 135k hp.

You have wrong numbers.

16DDH : 100,000ps
http://ja.wikipedia.org/wiki/%E3%81%B2% ... B%E8%89%A6

22DDH : 112,000ps

http://ja.wikipedia.org/wiki/19500%E3%8 ... B%E8%89%A6

So I link to the manufacturer of the power plants and you counter with Wiki?

Really?

Let's try this again.

Straight from GE:
http://www.geaviation.com/engines/marine/lm2500.html

Quote:

Output (Shp): 33,600

4 of those gets you 135k Shp.

The announcement (clearly in English, no need to translate):
http://articles.maritimepropulsion.com/?tag=/22DDH

Quote:

The propulsion system comprises four GE LM2500 gas turbines of 33,600 hp (25 MW) each giving a total power of around 135,000 hp (100 MW) in a COGAG arrangement giving a speed of 30 kt.

How else do you explain the same speed class "30+ knots" if the displacement grows by 35% without a corresponding rise in Shp.

maus92 - I would guess that any purchase of the F-35B will only occur when the Chinese threat becomes 'existential' to use that overused term. As you mentioned about Chinese blogs, a purchase of F-35B's gives Japan an aircraft carrier. That won't please its neighbors.

Also, given that construction times will take several years, there's no benefit to beginning a fight, by getting an aircraft carrier, before the Chinese amphibious threat materializes and everybody's scared.

maus92 wrote:

The problem is no official Japanese military sources has stated a requirement for V/STOVL fixed wing aircraft. From the same blog:

"[In reference to linked sources] Note however the distinct lack of official sources in the article, which should temper enthusiasms some."

"“Japanese accounts” tend to be from the military enthusiast magazines. These magazines are high quality production jobs, but they also tend to assume that Japan will get all of the latest and greatest American gear; they ran with the F-22 ball for years, putting the Hinomaru on Raptors until it was painfully obvious Japan was not going to be allowed to buy them."

"Admittedly the changes described–if real–point towards fixed wing aviation, but they also make good design sense, especially from a safety standpoint, and given the increase in overall ship size. That having been said, there’s no consensus that Japan needs carriers. Japan has no power projection ambitions that drive a need for carriers. For its strategic needs, Japan is the aircraft carrier.

It’s fun to imagine Japan having carriers again, but it just isn’t realistic."

http://newpacificinstitute.org/jsw/?p=1482

However, there are Chinese bloggers and state controlled media sources that claim the Japanese are planning for the F-35B version to equip these vessels, but that plays more for their domestic political need to question Japanese intentions rather than a reflection of future Japanese policy.

Again Maus, if you read my comments in the previous page, you really need to dig deeper than "official plans." Japan they have developed significant power projection capabilities even without a dedicated doctrine. In general Mizokami doesn't take much of a position either way on it (though his colleague suggests that might undertake operations in the Strait of Hormuz ". However Christopher Hughes wrote an excellent work "Japan's Remilitarization," which argues that the nation is becoming a more normal power and adding greater power projection capabilities. Its worth a read, given he uses a lot of qualitative and quantitative analysis.

The rest I'll just repost what I said before.

HB Pencil wrote:

While there are no official plans to buy the F-35B (or even the the initial steps to start such a program)... there are alot of signs on the margins in Japan that it could move toward such a capability in a decade's time.

The problem is that Japan doesn't have an amphibious warfare doctrine and a very immature strategic discussion for its need.... though it possesses one of the world's largest collection of such vessels (three Osumis, nearly a dozen smaller vessels.) I think the critical part is political direction. Right now the defense policy debate in Japan is unsettled, particularly on the issue of out of area operations. Once more clarity is achieved (and possibly a constitutional amendment is reached) for peacekeeping/disaster relief, then you might see a more cohesive policy emerge on Amphibious warfare. And the Navy is aware of that and seems to be planning for that accordingly. Furthermore the development of Chinese anti-access capability may well spur the MSDF to obtain more fleet defense capabilities, and the F-35 could play an important part. Its just really uncertain right now.

As for the 22DDH, the MSDF has put some thought into its amphib role. You don't make specifications to potentially carry 400 troops and 25+ trucks if you're only going to undertake anti-sub ops. Certainly it would need alot of reworking to utilize the F-35B, however I don't think its going to be much more than what the US navy faces with some of their own Amphibs.

Again this ALL is dependent on what happens in the political arena... but I wouldn't say that there is no thought going towards the F-35B. Its just that its far to premature for such discussions to occur.

SpudmanWP wrote:

So I link to the manufacturer of the power plants and you counter with Wiki?

Really?

Let's try this again.

No, you don't need to try. You lost. From IHI's own 22DDH page.

http://www.ihi.co.jp/ihi/press/2011/201 ... index.html

Quote:

??? ? ?????????

SpudmanWP wrote:

So I link to the manufacturer of the power plants and you counter with Wiki?

Really?

Let's try this again.

No, you don't need to try. You lost. From IHI's own 22DDH page.

http://www.ihi.co.jp/ihi/press/2011/201 ... index.html

Quote:

112,000 Horsepower

Helicopter dock ships boost defence by: MARK DODD : The Australian Feb 22, 2012

http://www.theaustralian.com.au/nationa ... 6277605880

"THE arrival in 2014 of the first of two 27,000-tonne Landing Helicopter Dock warships represents the biggest change to Australia's "force projection capability" since the navy's first aircraft carrier was acquired more than 60 years ago, Defence Force chief General David Hurley said yesterday.

Speaking at a key defence conference in Canberra, General Hurley said restructuring of the army's three combat brigades into an amphibious assault force - the most ambitious revamp of Australian Defence Force doctrine in decades - was on track to enable company-size ship-to-shore landings by 2018....

...The challenges in creating an Amphibious Task Force (ATF) should not be underestimated, he warned.

Much would be learnt from the shared experiences of the US Marine Corps, units of which will soon to be based in Darwin, and its British counterpart, the Royal Marines, General Hurley said.

As reported in The Australian in December, the testbed for the new capability will be the Townsville-based 2nd Battalion Royal Australian Regiment, just returned from Afghanistan.

However, outside Afghanistan, the Australian Defence Force's primary operating environment extends from the eastern approaches of the Indian Ocean to the island states of Polynesia and from the equator to the Southern Ocean.

"This area encompasses 25,000 islands, 85,000km of navigable waterways.

"The ADF must be able to maintain situational awareness across this vast area and must be capable of responding swiftly and decisively to a range of scenarios," General Hurley said...."

At the jump URL there is only talk about F-35s which has already been covered in a different thread.

The announcement from the shipbuilder is likely a misprint (or an idiotic copying of wiki). The engine MFG (along with several news articles) says 135k hp.

This is backed up by common sense (unfortunately not so common nowadays) when you look at the ratio of its increase in size and its speed.

SpudmanWP wrote:

The announcement from the shipbuilder is likely a misprint.

Quote:

This is backed up by common sense

Well, you can use one since you are clearly lacking one.

So you believe a single announcement from the shipbuilder over multiple references from the maker of the engines themselves?

SpudmanWP wrote:

So you believe a single announcement from the shipbuilder over multiple references from the maker of the engines themselves?

Yes, because IHI's the one that's building the ship AND the gas turbine(LM2500 used by JMSDF are license produced by IHI, not directly imported from the US), and they should know better than anyone how much horsepower their ship has.

Forum: General F-35 Forum

Possibility small STOVL carrier USN/USMC