Submarine Matters provides an expanding database on submarines worldwide. Australia should contract in 2016 to only buy a batch of 6 Shortfins - then, in the 2030s, decide whether to buy: 6 more Shortfins or 6 Barracuda SSNs or 4 Virginia SSNs. With increasing numbers of Chinese, Russian and Indian SSNs in Australia's region Australia's Shortfins cannot attain any 2016 Defence White Paper goal of being "regionally superior". Australia would need to buy SSNs to be "superior".
October 18, 2016
China Experimenting With New Submarine Detection Concepts
“Is China’s latest space
mission a step towards PLA tracking of nuclear submarines?”
Chinese scientists are working on a space-based device
that could track gravitational ripples produced by submerged submarines
China’s manned space programme has so far given its
astronauts few opportunities to fulfil military roles, but that will all change
when its space station is completed in the next six years.
One task on their to-do list could be detecting and
tracking nuclear submarines from space, using a technological breakthrough
achieved by Chinese scientists.
The two-man Shenzhou XI spaceship [for the Shenzhou 11 Mission]that blasted off from
the Jiuquan Satellite Launch Centre in Inner Mongolia on Monday morning will
soon dock with the Tiangong-2 space laboratory, launched last month, which is
carrying the world’s first space-based cold atom clock.
timepiece shares its core technology with cold atom interferometers, which can
measure tiny changes in gravitational pull with unprecedented sensitivity, and
one of the devices, to be built and put on the Chinese space station, could
potentially be used to track nuclear submarines.
Nuclear submarines can be massive, with the largest
measuring more than 170 metres in length and displacing 48,000 cubic metres of
water, and when they cruise several hundred metres below the ocean’s surface
they generate many gravitational ripples. An extremely sensitive detector could
catch and analyse the invisible ripples to locate and follow the submarine.
Using cold atom interferometry to detect submarines is a
controversial technology, with some scientists saying the enormous engineering
challenges involved mean it will never work, especially over the long distances
involved when using a space-based platform. Others think it’s worth a try.
China could be the first nation to do so, according to a
researcher at the Beijing-based China Academy of Space Technology, which has
initiated and designed most of China’s space projects.
The cold atom interferometer would be part of a
super-cold atom laboratory in the space station’s experimental module, said the
researcher, who declined to be named because he was not authorised to speak to
the media about the project.
“The technology’s potential military value is not
discussed in public, but it’s an open secret in the research community,” he
Professor Tu Liangcheng, who has studied the precise
measurement of gravity at Wuhan’s Huazhong University of Science and
Technology, said the Chinese government had substantially increased funding for
submarine detection technology in recent years.
“There is a shift in the navy’s attitude to submarine
warfare,” said Tu, who has been involved in military research projects.
In the past, China paid more attention to developing its
own submarines and the technology to make them quiet, powerful and able to stay
submerged for longer. It largely ignored the activities of other countries’
nuclear submarines, unless they ventured into Chinese waters.
But funding for submarine-hunting technology, including
gravitational measurement, had now increased significantly, Tu said.
The change reflects China’s ambition to develop a
“blue-water” navy able to protect its national interests along important
maritime trade routes spanning the globe.
Tu said the Chinese navy desperately wanted to be able to
track foreign nuclear submarines, but it was 30 years behind the capabilities
of the United States when it came to submarine-detection technology.
“Now we have enough money, and China’s strength in this
field of research in on par with the US and Europe,” Tu said. “But the pressure
is high, there is high expectation of a quick breakthrough, and we are short of
There are many ways to measure gravitational variations.
The US-German gravity recovery and climate experiment (Grace) mission, launched
in 2002, uses a pair of satellites to measure “bumps” – fluctuations – in the
earth’s gravitational field.
But the cold atom interferometer to be placed on the
Chinese space station should be more precise because it will be able to measure
bumps at the atomic level.
Because the movement of single atoms is difficult to
observe directly, the device will split a beam of slow-moving atoms in two and
then merge the beams to produce a band with interference patterns.
The up and down movements of the atoms caused by gravity
would change the look of the patterns, and scientists could use the information
to detect gravitational anomalies in a specific area.
Professor Zhan Mingsheng, who led a research team
studying space-based cold atom interferometers at the Chinese Academy of
Sciences’ Wuhan Institute of Physics and Mathematics, said Chinese scientists
would be able to shrink the device, currently the size of a room, to something
that could fit comfortably into the back of a car.
But he was sceptical about whether the technology would
be able to detect a submarine in the foreseeable future.
“The biggest problem is noise,” he said. “The technology
is very sensitive indeed, but also because of the sensitivity it can become an
ear that can hear everything. The signal that you want to detect will simply be
drowned out and lost in the background noise.”
The device would also suffer disturbances on a large
platform such as the space station, where a lot of equipment could cause
trembles. Even an astronaut’s cough could produce a false alarm, Zhan said.
The space-based detector would also have to compete with
other platforms, such as planes and ships, which were closer to the target and
likely to produce more precise locking, even though they could not offer the
same global view as the space station, Zhan said.
Once a nuclear submarine entered a big, deep ocean such
as the Pacific, it used to be believed that it would remain undetectable until
it surfaced. But a space-based submarine detection platform could locate it
Besides the cold
atom interferometer, China might consider other unconventional ways to detect
Nuclear submarines’ fission reactors produce neutrinos, extremely
small particles can pass through materials such as water and walls without
effort, potentially exposing a submarine’s location.
China has built some of the world’s largest and most
advanced neutrino detectors, one at Shenzhen’s Daya Bay nuclear power plant and
the other at a hydropower station in Sichuan, which at 2.4km below the earth’s
surface is the world’s deepest underground laboratory.
Cao Jun, the researcher who led the Daya Bay neutrino
detection project, said that detecting the elusive particles from a source 50km
away, using current technology, required a detector weighing 20,000 tonnes. But
new neutrino detection technologies were emerging, which might satisfy the
military’s need for a portable platform.
A future technological breakthrough might enable
scientists to develop neutrino detectors that could be placed on ships or space
stations, Cao added.
The US and Europe also launched cold atom interferometer
projects, but they were either cancelled or delayed, mainly due to funding
shortfalls, and some Western scientists have expressed interest in joining the
South China Morning Post article 1. Do you think China might deploy these technologies as submarine detectors in the next 20 years? 2. Which technology, interferometers of neutrino detection, might hold the most promise?