Sunday, August 27, 2017

Naval vessels, shadowy by intent, are hard for commercial ships to spot

August 25, 2017

HONG KONG — The tropical sky off Singapore was utterly dark when an oil tanker plowed into the side of the American destroyer John S. McCain before dawn on Monday (Aug 21) — but the moonless night may have been only one of the reasons that the tanker’s crew may have had trouble seeing a warship in their path.

Hard to see and hard to track electronically, naval vessels have long posed special perils to night-time navigation. That has proved deadly this summer in crowded waters like those near Singapore and Tokyo, where another American warship, the Fitzgerald, was struck by a cargo freighter under a waning crescent moon on June 17.

The issue has prompted growing alarm in the commercial shipping industry — which has started warning merchant vessels to be extra careful around warships — and in the United States Navy, which began pausing its worldwide operations this week for a day or two to allow time for safety reviews.

“There have been four this year for the US Navy, and the Singapore navy has experienced one or two” collisions with commercial ships, said Captain Raymond Ambrose, the president of the Singapore Nautical Institute. “We need an attitude of defensive driving out at sea.”

Naval ships, designed to avoid detection by enemy fleets and aircraft, are exempt from an international requirement that vessels automatically and continuously broadcast their position, course and speed. They tend to have dimmer lights than many commercial vessels, making them harder to pick out. They are painted gray to blend into the sea during wartime but become even more difficult to spot at night. And a growing number of modern naval vessels, including the USS McCain, are designed to scatter incoming radar signals, so that they are less detectable.
The Maritime and Port Authority of Singapore (MPA) told The Straits Times this week that the government’s vessel traffic information system had not even known the McCain was there until the tanker, the Alnic MC, carrying 12,000 tons of fuel oil, delivered a crushing blow to the warship’s left side.

MPA told The Straits Times that it had not detected the destroyer on radar and that its traffic information system had not picked up data on the ship. In addition to radar, traffic information systems rely on data from the so-called Automatic Identification Systems that all but the smallest commercial vessels are required to use to broadcast information about their whereabouts.

Military vessels typically carry the systems but often turn them off because the captains do not want to reveal so much information. MPA had no immediate comment or elaboration on its statement to The Straits Times. A US Navy spokesman declined to comment on what systems were operating aboard the McCain at the time of the accident, saying that the navy’s focus remained on finding the missing sailors.

The difficulties with spotting naval vessels are amplified in busy waters — and those around Singapore are among the most crowded in the world because the city-state lies at the entrance to the Strait of Malacca, through which nearly all of East Asia’s oil imports and a large share of its seaborne exports move.

The congestion prompts military and commercial crews to turn off the early warning systems that alert them to potential collisions, said Captain Harry Bolton, the director of marine programs at California State University Maritime Academy and a merchant marine officer who has traversed the waters near Singapore dozens of times.

Modern ship radars automatically calculate the closest point at which other vessels will approach them. The ship’s officers program the radars with a certain radius — typically up to around 3km — and if any other vessel passes inside that radius, a beep begins sounding on the bridge.

The beeping can be switched off only when someone on the bridge hits a button to do so, acknowledging that the warning has been received. But bridge crews commonly turn off the systems near Singapore because other vessels are frequently less than 2km away, so the beeping would be almost continuous.

“You turn them off,” Capt. Bolton said. “I can see everything, and I can look on radar.”

But ships like the McCain, a Burke-class destroyer, are considered among the US Navy’s best examples of vessels with a smaller radar signature, according to several former officers. They are low to the waterline, with equipment masts tilted to the ship’s stern, rounded edges and no large “citadels” rising high off the deck, like those on cruisers.

While commercial vessels traversing the Strait of Malacca illuminate their hulls and the waters immediately around them so that they can spot any pirates who may be trying to climb aboard, heavily armed naval vessels with large crews have little to fear and are less lit up. Sometimes they appear like shadows moving among immense freighters resembling bright Christmas trees.

To better negotiate the Strait of Malacca, commercial ship captains sometimes dispatch two crew members to the bow with radios to tell bridge officers about hazards ahead, said Mr Tim Huxley, the chairman of Mandarin Shipping, a Hong Kong shipping line.

Unlike the aviation industry, which also has to worry about congestion and collisions, the shipping industry has not instituted emergency avoidance systems.

Regulations in the US, Europe and other large aviation markets require that the newest planes have electronic systems that communicate with each other almost instantly when a collision appears likely and recommend a coordinated response to the pilots. One pilot might be told, for example, to “climb, climb”, while the other might be told to “descend, descend”.

By contrast, collision avoidance systems in ships do not have the ability to coordinate actions with each other, experts said. Introducing that capability would be difficult.

The United States and the European Union have worked closely with Boeing and Airbus to push for more sophisticated collision avoidance systems aboard aircraft, and are now working with China as Beijing starts building its own commercial aircraft. But ships are built all over the world with limited coordination.

The United Nations-affiliated the International Maritime Organization does regulate international shipping. More than 170 countries are members, and the group has been cautious about imposing requirements that ship-owners in developing countries might struggle to meet. But efforts are underway to develop such systems, as part of an industry effort to develop autonomous ships.

Many commercial shipping experts say that the difficulty of seeing navy ships is just part of the picture. They suggest that the USS McCain, with its powerful engines, advanced electronics and nimbleness, should never have moved into the tanker’s path, and they have been asking whether steering difficulties or poor bridge communications aboard the destroyer may have been factors. The US Navy has said the ship’s steering system showed no signs of failure, though it has cautioned that the cause of the accident is still under investigation.

Aboard the McCain, “you’ve got power and maneuverability — if you want to get out of the way, you can do it pretty quickly,” said Mr Arthur Bowring, who retired in November after 20 years as managing director of the Hong Kong Shipowners Association.

Recent trends in commercial ship design have made the danger of collisions much more serious. Ship-owners have been ordering larger and larger freighters and container ships in the past decade. Since most ship controls are now electronic and practically no muscle is required, it takes about the same number of crew members to operate a medium-size freighter as a very large one.

But big vessels can be hard to control. “We’re dealing with larger and larger vessels,” said Captain Andrew Kinsey, a senior marine risk consultant for Allianz, the big German insurer, “and the confined waters are not getting any bigger.”


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