Tag Archive for: search and rescue

Lessons for Australia after loss of Indonesian submarine

The loss of any submarine should be a catalyst for countries with submarines to review the likely causes and responses to determine if any lessons can be learned, in much the same way that airlines seek to learn from air disasters.

The tragic sinking of the Indonesian submarine KRI Nanggala 402 with its 53 crew has added significance for Australia because of our proximity, being between Australia and the highly contested South China Sea. What submarine search and rescue capability does Australia have and what is available in the region?

Although the Australian frigate HMAS Ballarat arrived early in the area where the Nanggala went missing, its sonar isn’t optimised for searching for wrecked or disabled vessels on the seabed. The wreck of the Nanggala was first detected by Indonesia’s KRI Rigel hydrographic survey vessel and confirmed by Singapore’s MV Swift submarine support and rescue vessel.

For the crew to escape or be rescued from a submerged submarine, the vessel must be lying intact on the seabed with survivors in at least one watertight compartment.

While accidents such as fires, floods and power failures do occasionally occur in submarines, an accident rendering a submarine incapable of surfacing is extremely rare. If a submarine sinks irretrievably, it’s even rarer that there are survivors to escape or rescue. More than 90% of the seabed is deeper than the crush depth of combat submarines, as was the case with the Nanggala.

The Royal Australian Navy’s six Collins-class submarines are based at HMAS Stirling, south of Perth, as are its two submarine rescue ships, MV Besant and MV Stoker. A rescue submersible, LR5, owned and operated by JFD Australia, is located nearby.

Considering the time required to install the LR5 system and the transit speed of the Besant and Stoker, it’s unlikely that the ships would be able to respond meaningfully to a disabled submarine any further away than Adelaide or Broome, and even that would require survivors to be contained in good conditions until a rescue could be attempted.

This raises a question of how the Australian Defence Force would respond to a RAN submarine that was disabled on the seabed further away.

The LR5 rescue system is air-transportable in the ADF’s C-17 transport aircraft, so it can be deployed to suitable ships that happen to be in the right place and are available to respond to disasters under the Vessels of Opportunity (VOO) program. Offshore oil and gas rig support vessels, for instance, typically have the necessary deck space and systems for the submarine rescue equipment. There are many such VOOs to the northwest of Australia and in Southeast Asia.

Australia could also seek the assistance of other nations such as Singapore with its Swift rescue craft.

Unfortunately, with the occasional exception of a vessel in Bass Strait, suitable VOOs are rare on Australia’s east coast. If a RAN submarine got into trouble off the east coast, where they frequently exercise, there probably wouldn’t be a rescue ship available in time.

We could not afford the cost of having dedicated submarine rescue ships ready on the east coast or in most other areas where RAN submarines might operate, nor should that be necessary.

A better option would be to require certain ships designed for other duties to be able to embark and use the submarine rescue system. For example, an ability to embark and operate the full deployable submarine rescue system could be a capability requirement for the replacement for the landing ship HMAS Choules.

Until a few years ago, a ship was located at Western Port in Victoria tasked with RAN recruit sea training. It was also capable of supporting the deployable submarine rescue system. The RAN would benefit from a new recruit sea training vessel that could support diving and salvage operations, and submarine rescue. Such a vessel could provide the close escort for submarines doing sea trials off Adelaide following construction or maintenance, while simultaneously conducting recruit sea training.

In a Strategist post last year, I suggested that a support ship as a base at Manus Island would provide more value and flexibility than fixed infrastructure. Such a ship could be designed and built to accommodate the deployable submarine rescue system. A large fleet support ship need not be overly expensive; it could be built to commercial standards and operated by a core civilian crew as are current navy support ships Sycamore, Besant and Stoker. Navy and contractor personnel needed to support RAN ships could be embarked as ‘special personnel’, not crew, on a fly-in, fly-out basis.

I suggested that a Manus Island-based support ship should be optimised to support the Attack-class submarines that are being built for the RAN, but it should also be able to support destroyers, frigates and small vessels.

As the submarine force grows from six to 12 vessels, it’s likely to have a permanent presence on both coasts of Australia. A support ship, with submarine rescue compatibility, could be based on the east coast, offering flexibility to relocate as operational situations demand.

If Australia’s security situation continues to deteriorate, the government might recognise that nuclear-powered submarines are considerably more effective than conventional submarines and offer better value for money. Nuclear-powered vessels are not authorised to enter Sydney Harbour. A fleet support ship optimised for submarine support could be based in Sydney for conventional submarines or located elsewhere if nuclear-powered vessels are acquired.

The nuclear question is vexing when it comes to expenditure on submarine rescue systems. Why should Australia spend significant funds on world-class rescue systems and yet expect submariners to go to war in conventional diesel boats against superior nuclear-powered submarines?

Is nuclear power the right choice for our submarines, but not politically popular? As ASPI’s Peter Jennings wrote last week: ‘When it comes to defence and security, governments need to do what is right for Australia’s interests, not necessarily what is popular, but it’s clear that public opinion has been ahead of government on the big strategic issues for some time.’

To encourage discussion on the nuclear issue, the Submarine Institute of Australia will convene a seminar in Canberra on 15 July, ‘Might submarines lead a nuclear industry in Australia? Continuing the conversation’.

Regardless of whether we opt for nuclear or conventional submarines, Australia’s defence policymakers and capability developers need to consider the geographic limitations of our current rescue ships and whether there are relatively low-cost, flexible options that might increase the chances of a successful rescue if disaster strikes one of our submarines.

MH370: more clues, but no more money

Needle in a haystack

The team searching for missing Malaysia Airlines Flight MH370 in the vastness of the Indian Ocean off Western Australia is working with the slenderest of clues painstakingly drawn from minute fragments of evidence. (The Australian Transport Safety Bureau released its latest review of evidence this week.)

Over the past two years the searchers have been accused of everything from incompetence to malfeasance, and of overseeing a giant cover-up. But their harshest critics continue to conflate two key questions: who was responsible for the disappearance of the Boeing 777 with its 239 passengers and crew, and where is the aircraft now?

A 2014 report, variously described as originating from the FBI or Malaysian Police, said that MH370 pilot Zaharhie Ahmad Shah had previously plotted a course down into the southern Indian Ocean on a simulator. The searchers don’t dispute that the pilot may have been responsible for the disappearance but the likely crash area wasn’t defined by hypotheses about what Captain Zaharie might’ve done. Instead, the likely location was identified after months of work by the Defence Science and Technology Group, which analysed signals transmitted automatically by the satellite communications system on the jet as it made its lonely flight southward, and calculated when it would’ve run out of fuel.

Just after midnight on March 8, 2014, MH370 took off from Kuala Lumpur headed for Beijing with a final radio message bidding the KL tower ‘goodnight’. The jet didn’t arrive, and it was believed to have vanished along its scheduled route.

As MH370 flew, it automatically received or sent routine signals as ‘handshakes’ with a satellite linked to a ground station in Perth. That system worked independently from others controlled by the crew and was designed to provide data about the state of parts such as the engines. Technicians from Inmarsat discovered the ‘handshakes’ and realised that the jet must have flown on for hours. Two satellite phone calls made to MH370 had gone unanswered but analysis of the signals indicated the jet was heading south. Malaysian military radar had seen the jet making two turns which took it back over the Malaysian Peninsula. It then became clear that MH370 made at least one more turn to head south. Those three turns would have to have been made by a pilot.

With almost nothing else to go on, scientists were left to calculate the time it took for the signals to travel between the aircraft and the satellite, and hence to work out where MH370 was at that time. Two signals from the aircraft were different. One came early on, when the satellite communications system came back to life after a period of silence. And then, after the six hourly ‘handshakes’ came a signal which was out of sequence and, again, seemed to be the result of a power failure to the satellite communications system. The investigators believe that happened at 8:19am (WA time) on 9 March, after the aircraft ran out of fuel and the two giant engines flamed out—the left engine first and the right up to 15 minutes later.

Simulations by Boeing indicate that once the engines lost power, MH370 would likely have slowed and lost lift. Its nose would have dropped and it would have descended in a ‘phugoid‘ motion in a series of swoops. It’s likely that the jet fell very fast—up to 25,000 feet a minute.

As it gathered speed, it would gain lift and climb again. As that speed fell off, its nose would have dropped rapidly once more, the aircraft falling into another steep dive. That process is likely to have been repeated until it hit the water, probably with one wing down, according to Boeing. The impact would have been catastrophic; the discovery of ­pieces of the aircraft’s interior indicates that it broke up on impact.

Critics of the search strategy suggest that once MH370 ran out of fuel, the pilot glided it ­for 100 nautical miles and ditched it in the ocean far from the search area. But the Australian Transport Safety Bureau says analysis of the signals most closely matches a scenario in which there was no pilot at the controls at the end of the flight.

Examination of a crucial piece of wreckage indicates that when MH370 slammed into the ocean, a wing flap was in a “cruise” position and not lowered for a landing as it would have been had there been a pilot at the controls. The flap was likely torn from the jet as it hit the water and drifted for more than a year to the coast of Tanzania in East Africa. It was part of the right wing ­positioned next to another control surface known as a “flaperon” which washed up on Réunion Island.

The drift of wreckage allowed for a second line of investigation. CSIRO have been conducting experiments to work out where wreckage that drifted to Africa began its journey. Significantly, the conclusions about the likely location overlap those of the Defence scientists, just north of the current search area. Given that it’s consistent with two independent lines of enquiry, that’s now the target, if money’s found to continue the search.

Media reports this week have erroneously referred to a ‘new’ search area, lying north of that searched so far. In fact, the new area of interest lies along the seventh of a series of arcs calculated from the satellite signals. The scientists believe the aircraft is along that seventh arc, which continues through the major area already searched. It was one of the first areas covered but the view now is that search wasn’t wide enough and should be expanded by about 25 nautical miles on each side of the arc. That’d mean an additional 25,000 square kilometres to be covered and would, based on costs so far, require an additional $50 million.

The suggested area covers more rugged sea floor extending to the Broken Ridge escarpment. At up to 6 kilometres deep, it’s below the reach of the autonomous underwater vehicle now being used, though suitable equipment is available for hire. Mathematicians now estimate the chance of finding MH370 there as at least 85%, but it seems unlikely that Australia, Malaysia or China will put up the extra money. We might never definitively know where MH370 ended up.