Submarine & Other Matters

The misadventures of AUKUS robot AlboGov never cease. I publish on subs, other naval, nuclear weapons & broad political issues. Aussie sub changes are glacial: talk rather than actual new subs. The 1st Collins LOTE may secretly concern the US Combat System & be ready 2029. Trump may decide to cancel the AUKUS Virginia offer due to USN advice it needs all operational SSNs right through to the 2040s. My colleagues Shawn C and Gessler are excellent writers. Pete.

June 23, 2014

German Submarine Developments 1945-1960s - Work in Progress

The evolution of postwar German designed submarines - starting with the (what is now) TKMS 201 at the bottom of the diagram.

This study of German submarine developments is a work in progress which is extending from the immediate post World War Two era - through the 1960s launch of TKMS Type 205s - to the 212s. Many links are in German but Google and other websites can Translate the links into English or other languages.

Diagram of a Type XXI.

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Allied Derivatives of the German Type XXI

At the end of WWII the victorious allies benefited from Germany’s advanced U-boat developments which reached the most useful state of development in the Type XXI U-boat. The XXI's much higher battery capacity and snorkel resulted in a far lower “indiscretion [unsafe operating] ratio” and streamlined hull all allowed faster, longer duration and quieter submerged operation.

XXI designs influenced post-war submarines, including the:

- US GUPPY (greater underwater propulsion power program) improvements to the US Gato, Balao, and Tench class submarines;

- Soviet submarine projects designated by NATO as the Whiskey, Zulu and Romeo classes;

- Chinese built Romeo class submarines based on the XXI design via Soviet-supplied designs. The Ming class, is based on the Romeo design. Some Mings are still in operation in the PLA-Navy 2013 (2 Mings are being transferred to Bangladesh).

- UK Porpoise and Oberon classes,

- France, the XXI ex-U 2518 became French submarine Roland Morillot The XXI design influence the French Arethuse and Daphne classes, and

- Sweden’s Hajen class (built 1954-58) was also influenced by the XXIs.

Postwar Air Independent Propulsion (AIP)

Two German WWII internal oxygen supply AIP developments were tested by some victorious allies after WWII. But proved too problematic to be adopted. These technologies included the:

- Walter engine - hydrogen peroxide is used as a source of oxygen to burn diesel driving steam turbines. An article translated from German providing more detail on the Walter Drive (engine) is here. This technology proved too volatile and explosive to be safe, and

- closed cycle diesel engines - uses a submarine diesel engine which can be operated conventionally on the surface, but which can also be provided with oxidant, stored as liquid oxygen,. Considered dangerously explosive from fire, heat or sparks.

Postwar Transition

Between May 1945 and 1956 former members of the Kriegsmarine formed the nucleus of the German Mine Sweeping Administration amounting to a transition stage for the navy. In 1956, with West Germany's accession to NATO, the West German Navy, colloquially known as Bundesmarine (Federal Navy) was established. In 1956 East Germany formed the Volksmarine ("People's Navy").

Submarines ("U-Boots") were and are built at HDW dockyards at Kiel, Type 202 (Atlas Werke AG , Bremen) and the Type 207 ( Rheinstahl-Nordseewerke , Emden)

Type 201

350 tonnes surfaced
450 tonnes submerged

From around 1957 West German facilities to develop and construct submarines had been repaired, rebuilt or built. This included dockyards which had been destroyed by bombing in the war.

In West Germany The HDW 201s, launched in 1962, were Germany's first class of military submarines built after World War II.

Functions - They were designed to defend coastal (or littoral) Baltic-North Sea areas and with a total of 8 torpedoes or 16 sea mines

They were built out of a magnetic steel to counter the threat of magnetic naval mines, but this steel had been insufficiently tested and proved to be problematic in service with the Bundesmarine. Microscopic cracks in the pressure hull forced the cancellation of 9 of the 12 ordered submarines and the early retirement of the three completed boats. This led to the need for the Type 205s.

Type 202

100 tonne surfaced
137 submerged

2 built for West Germany at Atlas Werke AG , Bremen, in service 1965-1966 then scrapped

Type 205

205s mainly differed from the 201s in hull steel used. Various steels were tried in different 205 hulls. The most acceptable steel was found to be PN 18 S2, which was developed by the steel company Phoenix Rheinrohr . PN 18 S2 (is ST-52 the same steel?) has been used for all subsequent submarines for the German Navy up to Type 212A .

The Eleven Type 205s for West Germany were launched from 1962 to 1968 and operational between 1967 and 2004. The last 205 in service was U 12 eventually used as a test bed for new weapons systems until its retirement in June 2005.

Functions - Up until the fall of the Berlin Wall (1989) major peacetime functions most probably included providing a deterrent and electronic and special forces intelligence gathering missions against Warsaw Pact countries. If war broke out the 205's main function was to operate within the NATO structure specifically to defend against Warsaw Pact landing ships and other naval vessels threatening the Baltic and North Seas.

Type 206

450 tonne surfaced
498 submerged

18 built by West Germany HDW, Kiel

12 for West Germany to type 206 A

4 (plus 2 as spare parts) by Columbia 1973-1975

The following types were German designed and built but for export customers only - Type 207 (Kobben-"Seal" Class) and the Type 209

The 3 Gal ("wave") Class submarines for Israel (similar to the 206s) in service 1976-2002, 540 tonnes surfaced, 600 tonnes submerged, were German designed but for political reasons built in the UK at Vickers Shipbuilding and Engineering Ltd , Barrow-in-Furness

Type 212

The first batch of Type 212 submarines used the Kongsberg-MSI-90U combat system. The Kongsberg system was used due to contra-trade obligations with Norway.

The second 212 batch use a Atlas Elektroniks combat system - perhaps the ISUS 90 or the more advanced ISUS 2000) .

The DM2A4 heavy weight torpedo (export designation SeaHake mod4) is in service with the 212s, has been delivered to the Pakistan Navy for service in Pakistan's Agosta 90B submarines and has been selected by the Spanish Navy for its new S80A submarines. The DM2A4 torpedo's sonar system has a wide angle array and the torpedo utilizes an at least 50km long fiber optic cable. Due to the bandwidth of optical transmissions the torpedo works as an additional sonar sensor for the submarine.

Wikipedia-English sources used so far

http://en.wikipedia.org/wiki/Air-independent_propulsion#Internal_oxygen_supply

http://en.wikipedia.org/wiki/Type_XXI_submarine#Wartime_and_post-war_service

http://en.wikipedia.org/wiki/Air-independent_propulsion#History

http://en.wikipedia.org/wiki/Type_201_submarine

http://en.wikipedia.org/wiki/Bundesmarine

Wikipedia-German sources being used

Thankyou MHalblaub for drawing my attention to Wikipedia-German and other websites translated into English which have much more detail on German submarine matters :-)

http://de.wikipedia.org/wiki/Liste_deutscher_U-Boot-Klassen

http://de.wikipedia.org/wiki/U-Boot-Klasse_XXI

http://de.wikipedia.org/wiki/Wilhelm_Bauer_%28U-Boot%29

http://de.wikipedia.org/wiki/U-Boot-Klasse_201

http://de.wikipedia.org/wiki/U-Boot-Klasse_205

http://de.wikipedia.org/wiki/Klasse_206

http://de.wikipedia.org/wiki/U-Boot-Klasse_209

http://de.wikipedia.org/wiki/U-Boot-Klasse_212_A

[The shipyard HDW has his own ideas to a more advanced version called class 216 presented, which should have a greater range and a longer operating lifetime of a compared to the 212 Class almost 40 percent larger boat length. [18] Potential buyers of the 4000-t- Boats Australia could be that looking for a replacement for the submarines of the Collins-class is. [19] The submarines have 33 people crew. Instead of the outdated lead-acid batteries of any ancestors are here lithium-ion batteries can be used. [20]reference to 218SG]

http://de.wikipedia.org/wiki/U-Boot-Klasse_214

http://de.wikipedia.org/wiki/Liste_deutscher_U-Boote_%28nach_1945%29

http://de.wikipedia.org/wiki/Howaldtswerke-Deutsche_Werft

http://de.wikipedia.org/wiki/U_31_(Bundeswehr)

Other German sources being used

http://www.die-marine.de/_deutsch/schiffe/subm.htm The U-boat Arm of the German Navy
http://seefahrer.blog.de/tags/uboot/ Seafarer or Sailor blog

Pete

CIA's Operational Problems in Iraq

A hazard of life in Iraq

Only in American would a serious academic website like IntelNews publish an article about CIA officers in Iraq having problems talking to their sources, See the following IntelNews article by Joseph Fitsanakis of June 23, 2014 at http://intelnews.org/2014/06/23/01-1501/ :

"CIA ‘stripped of spies’ in embattled Iraq, say sources"

"The Sunni uprising in Iraq, in combination with the Shiite domination of the government in Baghdad, has drastically limited the ability of the United States Central Intelligence Agency to collect dependable intelligence, according to sources.

Newsweek’s veteran intelligence correspondent, Jeff Stein, said on Friday that the Agency had been “stripped of its spies” in the embattled country and was struggling to rebuild its network of assets. Stein cited “knowledgeable intelligence sources” as saying that the CIA had lost many of its sources inside the government in Baghdad, which is now firmly in Shiite hands.

Since assuming power in 2006, Iraq’s Shiite Prime Minister, Nouri al-Maliki, gradually purged most Sunnis from senior government positions, thus shutting down the CIA’s eyes and ears in Baghdad.

The intelligence-collection problem for the Agency has worsened since the breakout of the Sunni uprising in the west of the country, which has prompted mass defections of senior tribal leaders to al-Qaeda-inspired rebel groups. Many of these leaders were previously valuable sources of information for the CIA, which has traditionally had far more contacts with Iraqi Sunnis than Shiites.

To make things worse, says Stein, CIA operatives in Iraq are unable to travel outside of Baghdad due to the worsening security situation in the country. Instead, they remain “holed up” in the American embassy compound and rely almost exclusively on “technical means” of intelligence collection (and, one presumes, a variety of open sources).

Inevitably, the Agency is now much more reliant than usual on information provided by regional intelligence services, such as Turkey’s and Jordan’s, who still have agents on the ground in Iraq. One “former operative” who maintains contact with US embassy staff, told Newsweek that the CIA contingent at the US compound is “not being tasked to do a lot of stuff” and is currently “not doing much”.

Another former senior CIA operations officer said: “the train has left the station”, implying that it will be a long time before the Agency can rebuild its network of assets in the country. But a current US intelligence official told Stein that, although the Sunni insurgency took the CIA by surprise, “Washington had a clear picture” of the situation in the country and that its intelligence “capabilities are intact”."

Iraq: the ISIS crisis

Something I had published on Australia's ON LINE opinion on Friday June 20, 2014 http://www.onlineopinion.com.au/view.asp?article=16422 indicating "The US is neither all-seeing nor all-powerful. Australia, if it wants to be active in Iraq, cannot act alone so it must follow some country’s lead. With the US inevitably pivoting to Eastern European commitments (Ukraine) and Middle Eastern commitments (ISIS) Australia needs to contribute in some way to the shifting geo-political picture." :

Iraq: the ISIS crisis

By Peter Coates - posted Friday, 20 June 2014

The bloody progression of Islamic State in Iraq and Syria (ISIS) rebel forces to the outskirts of Baghdad continues with a wide range of outcomes possible. The rapid expansion of ISIS (also known as Islamic State in Iraq and the Levant (ISIL)) has come as a shock. This article attempts to present some issues that have received inadequate attention in mainstream media reporting on the ISIS crisis.

Although Islamic Sunni-Shiite hatreds have existed for around 1,400 years the Sunni rebels of ISIS are an unusually violent problem. This map gives one idea of how central Iraq is in the region and of the refugee (internally displaced people (IDPs)) problem created by ISIS’ advance. This smaller map is of the ISIS advance itself.

ISIS’ presence in Syria and Iraq is probably boosting the risk of international terrorism. It is Iraq’s huge amounts of oil, however, that differentiate Iraq from Syria. Several years of frequent suicide bombings in Iraq have sparked little media attention but ISIS seizing Iraqi regional cities and oilfields has rattled surrounding countries and is driving up world oil prices.

Unlike Syria, with few Westerners, Iraq hosts a large Western foreign contractor-government employee presence due mainly to oil.The UK Daily Mail reports that the US embassy in Baghdad's Green Zone has around 5,000 personnel making it the largest US embassy in the world. This may indicate that that US embassy is part of a huge diplomatic cocktail circuit or perhaps it has other functional priorities?

A powerful presence of Western government representatives in Iraq also responds to conflicting concerns of Iraq’s Shiite and Sunni neighbours. Iran has reportedly sent as many as 2,000 men from Quds special forces units of Iran's Revolutionary Guard into Iraq to boost defences against ISIS in and around Baghdad. This indicates how close the Shiite leadership of Iraq is to the Shiite’s leading Iran. It is also significant that Iraq has not protested against Syrian airstrikes launched by Syria’s Shiite government against ISIS convoys actually within Iraq (near the town of Al Qaim).

Sunni dominated governments, including Saudi Arabia and smaller Arab Gulf states, are nervous that regionally powerful Iranian forces may combine with Iraq’s to present a large Shiite military threat. Hence ISIS is semi-openly recruiting in Saudi Arabia. Iraq’s neighbours and the international economy generally are also concerned about rapid fluctuations in world oil price and production levels caused by the ISIS crisis.

It is unclear whether US military activity concerning Iraq will mainly be an airstrike or evacuation mission (or both). Iraq’s Sunni dominated neighbours may well decide not to host any US aircraft or drones that might kill ISIS Sunni rebels. To adjust to this limitation the US military reports that a US fleet is now sitting in the Persian (Arabian) Gulf. This fleet consists of: the carrier USS George H.W. Bush (helicopters for evacuation, strike aircraft and intelligence collection); the cruiser USS Philippine Sea (able to fire at least 122 cruise missiles); and three destroyers each able to fire 90 cruise missiles. Also in the fleet is the USS Mesa Verde an amphibious warship that can carry 800 marines, helicopters and Osprey tilt rotorcraft. The Age has published an article presenting eight military options Obama might be considering.

Baghdad’s location might make a Western evacuation by helicopter or road difficult. Baghdad is a 1,200 km round trip from the US fleet in the Persian Gulf and alternatively it would be a long trip by road south to Kuwait or Saudi Arabia. Baghdad is however a short road or helicopter trip to the Iranian border, hence Western talks with Iran probably include evacuation scenarios.

It was unclear whether Abbott’s comments relating to Iraq (when he met President Obama several days ago) ran too far in advance of any consultation with the Australian public, Parliament or Abbott’s own party room (see this youtube). How Australia could aid any US military or evacuation effort is a question mark. Australian assistance might be in the shape of use of one of Australia’s new E-7A Wedgetail aircraft for force communication or one of our Orions to gather intelligence. If the Iraq crisis runs into weeks or months the deployment of one of our ANZAC frigates might contribute to the US fleet effort. Some Australian army special forces might also be sent to contribute to the protection force [written before the Australian Government announced it was sending 30 SAS to Baghdad as a protection force] for the Western community in Baghdad’s Green Zone.

In the last 48 hours Iraq has formerly asked the US to launch airstrikes against ISIS. Critics from the right and left will damn the US for anything it does or doesn’t do. The US is neither all-seeing nor all-powerful. Australia, if it wants to be active in Iraq, cannot act alone so it must follow some country’s lead. With the US inevitably pivoting to Eastern European commitments (Ukraine) and Middle Eastern commitments (ISIS) Australia needs to contribute in some way to the shifting geo-political picture.

Pete

June 11, 2014

Australia's Future Submarine - Swedish vs German Claims

This article, Saab Story: Sweden's New Submarines, June 10, 2014, http://www.defenseindustrydaily.com/saab-story-swedens-new-submarines-024760/ appears to have been inserted by Saab and maybe the Swedish Government to understandably increase the chances that Australia's future submarine will be designed and partly built in Sweden. Japan's Soryu propulsion system is of course being considered by Australia and US input, or at least Lockheed Martin's, has for years been considered for the combat system. All may be even more complicated and multi-country than the Collins' deals 1980s-2000s.

The article however seems to avoid the issue that if TKMS still owns Kockums (as indicated here http://www.kockums.se/en/ ) then TKMS through Kockums retains many intellectual property rights that Sweden-Saab assumes are Sweden's rights. Intellectual property like the Stirling engine may be used in Australia's future submarine. But who owns the the intellectual property rights to the Soryu's Stirling engine and separately does Germany mostly own the licensing rights to the Soryu's diesel? Sweden-Saab? Germany-TKMS-Kockums as it applies to Japan? Where do Japan's submarine builders, Mitsubishi and Kawasaki, stand? It all needs to be clarified by German, Swedish, Japanese and Australian lawyers, businessmen and politicians. See also "The reported Swedish solution would buy [Australia's] ASC" below.

Here are the relevant parts of the article which is on the Defense Industry Daily website http://www.defenseindustrydaily.com/saab-story-swedens-new-submarines-024760/ :

Saab Story: Sweden’s New Submarines

Jun 10, 2014 18:46 UTC by Defense Industry Daily staff

.... In order to field their next-generation design, however, Sweden may have to do something unusual: partner with other countries…

....The A26 will be equipped with an air-independent propulsion (AIP) supplement to its diesel-electric systems,...

...The A26′s AIP system will be Kockums’ Stirling, which also equips Sweden’s 3 Gotland and 2 Sodermanland Class submarines, Singapore’s Archer Class Sodermanlund variant, and Japan’s Soryu Class.

...April 14, [2014] Saab to buy Kockums. Saab AB and ThyssenKrupp Industrial Solutions AG sign a non-binding Memorandum of Understanding concerning the sale of the Swedish shipyard ThyssenKrupp Marine Systems AB (formerly named Kockums), including its Malmo, Karlskrona, and Musko operations, to Saab AB.

“Both parties agree that during the negotiations phase, the integrity and the operating ability of ThyssenKrupp Marine Systems AB must be safeguarded. The transaction will be subject to regulatory approval. The negotiations between Saab AB and ThyssenKrupp Marine Systems AB are at an early stage and more information will follow.”

There’s a major backstory here. Sweden’s FMV effectively raided TKMS’ offices in Malmo “to take sensitive technological equipment,” but FMV says that since “…it was a transfer of defence material, belonging to FMV, all information regarding the transfer is classified as secret”. It’s generally believed that they came and took the A26 submarine’s plans, as well as a complete Stirling Air-Independent Propulsion system, which are technically owned by the Swedish state. [does Germany-TKMS agree it is legally owned by Sweden?]. A country that believes time is of the essence, and doesn’t want what it perceives as a hostile corporation to have leverage from holding state materials, might be inclined to move swiftly. The very fact that this happened speaks to how badly relations between Sweden and TKMS have deteriorated.

April 12, [2014]: Australia. The Collins Class was built around a Swedish design, and News Corp Australia says that Saab and the Swedish Government have been engaged in secret talks around a new joint submarine effort. That proposed approach may have the potential to cut through many of the dilemmas faced by Australia’s government, and Sweden’s as well....

The reported Swedish solution would buy [Australia's] ASC, and embark on a fully cooperative joint design for Sweden and Australia’s next submarines. Australia would receive a design that’s explicitly built for Australia’s needs – a necessary compromise for Sweden, whose needs are different. It’s also worth noting that the Japanese Soryu Class propulsion system which is attracting so much interest from Australia’s Navy is part Swedish. From industry’s point of view, making ASC part of Saab removes any conflict of interests with a foreign firm that acts as the project lead, creating both development jobs/skills, and production work. From the politicians’ point of view, a program that includes Sweden and Australia offers the added security of shared risk, and shared acquisitions.

Sweden is looking to re-establish an independent submarine industry (q.v. March 26/14), and their challenge will be buying enough talent, building an equivalent production workforce, and designing the new sub within Sweden’s budgets. Australia offers Sweden a development partner, and a workforce with good experience...."

PETE'S COMMENT

This whole matter still seems a political and legal mess or challenge, at least. If TKMS looks like it would lose Australia's future tender to build Australia's future submarine then TKMS will construct legal intellectual property right obstructions to make it very difficult for Saab to smoothly win the tender.

Pete

June 5, 2014

German Diesels and AIP? for Chinese Submarines

Chinese submarines are becoming harder to detect. in part, due to low acoustic signatures of German supplied diesel engines on China's Song and Yuan class submarines.

Conventional submarines built by Russia and (more strategically important to Australia) China are powered by German supplied submarine diesel engines. Also Germany has helped China set up a diesel engine factories. It is not known the extent to which Germany has consciously or unconsciously supplied details of submarine AIP engines and propellers which need to interact operationally with the diesels.

Unknowns

It would be interesting to know:

- if Germany or other countries have supplied any AIP or submarine propellers to China?
- what material might the Chinese submarine hulls be made of (steel, alloys, Anechoic tiles)?
- the latest details of Chinese submarine and ASW characteristics, capabilities and imports.
- also Russian (SSK) submarine and ASW characteristics and capabilities are interesting given the likelihood of Russian SSK and ASW exports and designs going to China.

The following article is a bit long but German submarine engine exports to China seem substantial. I've therefore bolded Germany, MTU and Man Diesel & Turbo for easier reading.

David Lague for Reuters (Indian edition) December 20, 2013, reports http://in.reuters.com/article/2013/12/19/breakout-submarines-special-report-pix-g-idINL4N0JJ0FM20131219 :

"Chinese military's secret to success: European engineering -

* Much of China's naval fleet powered by European diesel engines

* EU arms embargo doesn't cover dual-use technology

* Lucrative trade in dual-use components from Europe

* Germany's MTU supplies state-of-art engines for China's submarines

* China's whisper-quiet submarines pose biggest threat to adversaries

HONG KONG, Dec 19 (Reuters) - If the People's Liberation Army went to war tomorrow, it would field an arsenal bristling with hardware from some of America's closest allies: Germany, France and Britain.

Most of China's advanced surface warships are powered by German and French-designed diesel engines. Chinese destroyers have French sonar, anti-submarine-warfare helicopters and surface-to-air missiles.

Above the battlefield, British jet engines drive PLA fighter bombers and anti-ship strike aircraft. The latest Chinese surveillance aircraft are fitted with British airborne early warning radars. Some of China's best attack and transport helicopters rely on designs from Eurocopter, a subsidiary of pan-European aerospace and defense giant EADS.

But perhaps the most strategic item obtained by China on its European shopping spree is below the waterline: the German-engineered diesels inside its submarines.

Emulating the rising powers of last century - Germany, Japan and the Soviet Union - China is building a powerful submarine fleet, including domestically built Song [see German MTU diesel engines (16V396 units rather than the 12V493 units originally considered),] and Yuan-class boats. The beating hearts of these subs are state-of-the-art diesel engines designed by MTU Friedrichshafen GmbH of Friedrichshafen, Germany. Alongside 12 advanced Kilo-class submarines imported from Russia, these 21 German-powered boats are the workhorses of China's modern conventional submarine force.

With Beijing flexing its muscles around disputed territory in the East China Sea and South China Sea, China's diesel-electric submarines are potentially the PLA's most serious threat to its American and Japanese rivals. This deadly capability has been built around robust and reliable engine technology from Germany, a core member of the U.S.-led North Atlantic Treaty Organization.

Arms trade data from the Stockholm International Peace Research Institute (SIPRI) to the end of 2012 shows that 56 MTU-designed diesels for submarines have been supplied to the Chinese navy.

"They are the world's leading submarine diesel engines," says veteran engineer Hans Ohff, former managing director of the Australian Submarine Corporation, the company that built Australia's Collins-class conventional submarines.

MTU declined to answer questions about transfers to the Chinese navy, future deliveries or whether it supplies technical support or servicing. "All MTU exports strictly follow German export laws," a company spokesman said.

CHINA'S MILITARY MARKET

The Chinese defense ministry says the PLA's dependence on foreign arms technology is overstated. "According to international practice, China is also engaged in communication and cooperation with some countries in the area of weaponry development," the ministry said in a statement responding to this series. "Some people have politicized China's normal commercial cooperation with foreign countries, smearing our reputation."

Transfers of European technology to the Chinese military are documented in SIPRI data, official EU arms trade figures and technical specifications reported in Chinese military publications.

These transfers are crucial for the PLA as it builds the firepower to enforce Beijing's claims over disputed maritime territory and challenge the naval dominance of the U.S. and its allies in Asia.

China now has the world's second-largest defense budget after the United States and the fastest growing military market. Many of Europe's biggest defense contractors have been unable to resist its allure. High-performance diesels from MTU and French engine maker Pielstick also drive many of China's most advanced surface warships and support vessels, SIPRI data shows. Pielstick was jointly owned by MTU and German multinational Man Diesel & Turbo until 2006, when Man took full control.

Some military analysts remain skeptical about the quality of China's military hardware. They say the engines and technology the PLA is incorporating from Europe and Russia fall short of the latest equipment in service with the United States and its allies in Asia, including Japan, South Korea and Australia. This leaves the PLA a generation behind and struggling to integrate gear from a range of different suppliers, they say.

Others counter that China doesn't need to match all of the most complex weapons fielded by the United States and its allies. Even if it deploys less than the best gear, Beijing can achieve its strategic goal of blunting U.S. power.

"At what point do they become good enough?" says Kevin Pollpeter, a specialist on Chinese military innovation at the University of California Institute on Global Conflict and Cooperation at San Diego. "If they have sufficient quantities of good-enough weapons systems, maybe that will carry the day."

LIMITS OF EMBARGO

Russia remains China's most important outside source of arms and technical assistance. The Chinese navy's best-known vessel - its sole aircraft carrier, the Liaoning - was purchased from Ukraine. A U.S. Navy vessel nearly collided with a Chinese warship last week while maneuvering near the Liaoning, during a time of heightened tensions over Beijing's recent declaration of a new air-defense zone in the East China Sea.

European hardware and know-how fills critical gaps, however. It wasn't supposed to play out this way.

The European Union has had an official embargo on arms shipments to China since the 1989 Tiananmen crackdown. Washington imposes even tighter restrictions on transfers of U.S. military technology to China, inspiring energetic efforts by Beijing to smuggle American gear and know-how. Europe's embargo, however, has been far more loosely interpreted and enforced. Thus weapons and, perhaps more importantly for the PLA, dual-use technology have steadily flowed from America's European allies to China.

EU arms makers have been granted licenses to export weapons worth almost 3 billion euros ($4.1 billion) to China in the 10 years to 2011, according to official figures from Brussels collated by the London-based Campaign Against Arms Trade. EU governments approved the sale of aircraft, warships, imaging equipment, tanks, chemical agents and ammunition, according to official figures.

Michael Mann, an EU spokesman in Brussels, said the EU arms embargo issued in June 1989 "does not refer to dual use goods." It is up to individual member states to exercise control over such goods, Mann said.

From China's perspective, France and the UK interpret the arms embargo most generously, mostly blocking only lethal items or complete weapons systems. France was by far the biggest EU supplier, accounting for almost 2 billion euros of these licenses. The United Kingdom ranked second with almost 600 million euros, followed by Italy with 161 million euros. The value of weapons actually shipped is difficult to extract from the data because some countries, including the UK and Germany, don't report these figures.

The value of German export licenses for weapons was a relatively modest 32 million euros in the decade to 2011. However, EU arms trade figures don't include dual-use technology that in many cases can be sold without licenses. Examples of such technology include many kinds of diesel engines. The same applies to transfers of commercial aerospace design software that can be used for fighters, bombers and unmanned aerial vehicles.

Arms industry experts say dual-use transfers are almost certainly more valuable to the PLA than the actual weapons Europe has delivered. But it's impossible to calculate a hard number for European-Chinese trade: The EU lacks a consistent system for tracking these transfers amid the vast flow of goods, services and intellectual property to China. Europe shipped goods worth 143.9 billion euros to China in 2012, according to EU trade statistics.

Critics of the EU's arms trade with China say member states have failed to devise a system to enforce the embargo. They say this reflects the loose structure of the EU, where each member state interprets the restrictions differently according to domestic law, regulations and trade policies.

Geography plays a role, too: The distance between Europe and Asia means there is ambivalence about the rapid growth of Chinese military power. From Europe, China looks like an opportunity, not a threat.

SELLING COMPONENTS

The embargo is nevertheless an embarrassment for Beijing; senior Chinese officials routinely call for it to be lifted, and pressure from Washington keeps it in place. That means the sale of complete weapons like the pan-European Eurofighter, German submarines or Spanish aircraft carriers remain impossible for the foreseeable future.

In the meantime, Europe has discovered a lucrative trade selling components, particularly if they incorporate dual-use technologies that fall outside the embargo.

"Nobody sells entire weapons systems," says Otfried Nassauer, director of the Berlin Information Centre for Transatlantic Security and an expert on Germany's arms trade. "But components, especially pricey high tech components, that works OK."

Under Beijing's long-term policies to promote innovation, domestic arms makers are encouraged to import the foreign technology that China lacks. The challenge is to adapt this range of components and know-how into locally built weapons.

One example is how German engine makers have contributed technology to support China's expanding fleet of support vessels that monitor satellites and missiles.

Man Diesel & Turbo last year announced it would supply engines built under license in China for two new transport vessels for the China Satellite Maritime Tracking and Controlling Department, part of the PLA's General Armament Department (GAD). The GAD oversees weapons research and development and manages all of China's military and civilian space operations, including the tracking of satellites and missiles. The European engine maker will also supply gear boxes, propellers and propulsion control systems for the ships from its Danish manufacturing unit, it said.

A spokesman for Man Diesel & Turbo said about 250 of its engines had been made under license in China and supplied to the Chinese navy. The company also provided some selected services and spare parts including fuel equipment.

"All our business does fully comply with the applicable export control or embargo regulations set by Germany and the European Union," the spokesman said. He added that Pielstick brand engines supplied to the PLA navy by Chinese licensees were not subject to export approval. "None of these engines is specifically designed for military purposes," he said. "There is a broad variety of civil applications for these engines, too."

UNDERWATER DISASTER

Reliable submarine engines top Beijing's shopping list, and China's navy has good reason to want the best.

In the late spring of 2003, a disabled Chinese submarine was found drifting, partly submerged, in the Bohai Sea off China's northern coast. When the boat was raised, rescuers found all 70 of its crew dead. Their deaths were blamed on "mechanical difficulties," according to reports at the time in China's state-controlled media. The outcome of any inquiry was never made public.

Since then, submariners all over the world have speculated about what went wrong aboard Ming class submarine number 361, a Chinese copy of an obsolete Russian design. Most agree it was probably a fault with its diesels. The engines either didn't shut down immediately when the submarine submerged, sucking the oxygen out of the hull in minutes, or the suffocating exhaust vented internally rather than outside the hull. Either way, the outcome was catastrophic.

It was one of Communist China's worst peacetime military disasters, and the navy chief and three other senior officers were sacked. But the People's Liberation Army navy was already taking delivery of diesels from MTU. Engineers at the Wuchang Shipyard on the Yangtze River were fitting these power plants in China's first indigenously designed and built conventional submarines, the Song class.

MTU is a unit of Germany's Tognum Group, which is jointly owned by UK-based multinational Rolls Royce Group PLC and Germany's Daimler AG. Contracts with the PLA and powerful defense manufacturers give MTU and its parent influence in competing for contracts in China's massive civilian market. China's biggest arms maker, China North Industries Group Corporation, or Norinco, has been making MTU engines under license since 1986.

In 2010, Tognum opened a joint venture with Norinco to assemble large, high speed MTU diesel engines and emergency generators at a plant in the city of Datong in Shanxi Province. A major goal of the joint venture is to win orders for emergency backup generators for China's expanding roster of nuclear power plants, Tognum said in a press statement. MTU engines are also built under license at the Shaanxi Diesel Engine Heavy Industry Co Ltd, a subsidiary of one of China's two sprawling military and commercial shipbuilders.

Submarine diesel technology is hardly new, but these engines are built to exacting standards to ensure reliability under extreme conditions. MTU has been building them for more than 50 years. The engine delivered to China for the Song and Yuan classes, the MTU 396 SE84 series, is one of the world's most widely used submarine power plants. Each of the Chinese submarines has three MTU diesels, according to technical specifications listed in Chinese military affairs journals and websites.

China's military is reluctant to acknowledge the role of foreign technology in its latest weapons, preferring to recognize the performance of its domestic designers and arms makers. But articles in maritime magazines and naval websites have credited the close relationship between MTU and China's domestic industry for providing the Song class with "the world's most advanced submarine power system."

In its promotional brochures, MTU says almost 250 of these engines in service with submarines around the world have racked up over 310,000 hours in operation. Some have also been fitted to nuclear submarines as back-up power plants, the company says. MTU also sells different versions of the 396 series for use in locomotives, power generation and mining.

A spokesman for the Federal Office for Economics and Export Control (BAFA), the German authority that has to approve dual-use exports, said exports of diesel engines built especially for military use would be illegal. Engines that can be used for both civilian and military purposes would have to be approved by BAFA, he said - and in the case of China, such dual-use engines "would probably not be approvable." He declined to comment specifically, however, about the MTU diesel engine sales to China's navy.

STEALTHY SUBMARINES

Top quality diesel engines like the MTU designs minimize vibration and noise, reducing the risk of detection by enemy sonar. In the hands of a capable crew, modern diesel submarines can be fiendishly difficult to detect. When using their electric motors, they are significantly stealthier than nuclear submarines such as those in service with the United States, naval warfare experts say. For a relatively modest investment, a diesel electric sub could sink a hugely expensive aircraft carrier or surface warship.

With whisper-quiet engines, China's best conventional submarines armed with modern torpedoes and missiles may pose the biggest danger to any potential adversary - including the U.S. Navy. Beijing's naval strategists are banking on their growing fleet of subs to keep the Americans and their allies far away from strategic flashpoints in the event of conflict, such as Taiwan or disputed territories in the East China Sea and South China Sea.

That means the Pentagon's favored method of modern warfare - parking carriers near the coast of an enemy and conducting massive air strikes - would be very risky in any clash with China.

The PLA navy has already demonstrated this capability. In 2006, a Song class submarine shocked the U.S. Navy when it surfaced about five miles from the U.S. aircraft carrier Kitty Hawk, well within torpedo range, in waters off the Japanese island of Okinawa. The Chinese boat had been undetected while it was apparently shadowing the U.S. carrier and its escorts, U.S. officials later confirmed.

PLA submarines are becoming much more active. Recorded Chinese submarine patrols increased steadily from four in 2001 to 18 in 2011, according to U.S Naval Intelligence data supplied in response to freedom of information requests from a Federation of American Scientists researcher, Hans M. Kristensen.

A senior U.S. Navy official declined to comment on German delivery of diesel engines to China, but said the United States is well aware of the challenges such submarines pose. "Diesel engines are notoriously difficult to detect, but we are also always investing in improving own capabilities to make our submarines quieter," the official said. (Additional reporting by John Shiffman in Washington and Sabine Siebold in Berlin. Edited by Bill Tarrant and Michael Williams)"