Satellite Search and Rescue Imaging Finally Comes of Age

Seventeen hundred miles off the Sumatran Straits, a solo sailing yacht is hit by a drifting sea-land cargo container.

Within minutes, in the current film “All is Lost,” Robert Redford’s character is waist-deep in water.

Although Redford manages to jerry-rig his sputtering maritime band radio just long enough to make three SOS calls, he’s soon forced to abandon ship.

Something just as catastrophic may have happened this past June to the missing SV Nina — a fully-crewed, 70-foot American schooner — while en route from New Zealand’s North Island to the east coast of Australia.

But in such rare cases when all emergency communications fail, satellite imaging could now make the crucial search and rescue difference.

“Until now, it’s not been realistic to use them in real time [for searches] unless you were a government agency,” said Jeff Glickman, a nationally-recognized Seattle-area satellite image analyst. “What’s changed in the last year is the development of certain polar orbiting commercial satellites capable of scanning the earth quickly. We’re at a tipping point where you could catch a water craft on an image at least once a day.”
With seven aboard, including six Americans, the Nina’s last confirmed, but undelivered satellite phone text message, stated that that the schooner had had its storm sails stripped away and was encountering 110 km/hour wind gusts and 8-meter ocean swells.

By then, the craft was estimated to be some 370 nautical miles West-North-West of Cape Reinga in the Tasman Sea, between Newcastle, Australia and Opua, New Zealand.

However, Maritime New Zealand’s Rescue Coordination Centre officially suspended its search after 12 days, which included covering some 737,000 sq. nautical miles with a Royal New Zealand Air Force P-3 Orion aircraft.

Meanwhile, friends and families of Nina’s missing crew contacted DigitalGlobe DGI -0.08%. The U.S.-based satellite operator readily agreed to reposition its constellation of commercial satellites to collect high-resolution imagery of almost 500,000 square kilometers — an area larger than California. DigitalGlobe then used its recently-acquired Tomnod crowdsourcing online platform to aid in the search.

DigitalGlobe recruited thousands of online users to help sift through massive amounts of sat-photo images and tag anything that might look like the missing craft or its life raft.

An image taken September 16th by DigitalGlobe’s QuickBird satellite was flagged as potentially being the missing yacht by multiple Tomnod users.

The image was then sent to Maritime New Zealand where it was thoroughly analyzed in terms of whether it would “constitute sufficiently-compelling new information to resume active searching,” says Nigel Clifford, Maritime New Zealand’s General Manager for Safety and Response services, which oversaw search and rescue for the Nina. It was then determined, says Clifford, that the QuickBird photo isn’t likely to contain an image of the missing yacht.

“And given the elapsed time, survival under this scenario is most unlikely,” said Clifford.

“All is Lost” only reinforces just how difficult open ocean search and rescue can be. Redford’s full-sized life raft passes within half a mile of two large cargo ships and even with flares still can’t get their attention.

For its part, the Nina was equipped with three, independent distress alerting or communication devices aboard, including an electronic marine distress beacon.

Clifford says, to date, no signal beacon has been detected.

“The most probable scenario remains that the vessel was overwhelmed in a catastrophic event shortly after its last [known] communication on June 4th,” said Clifford. “Examples might include rapid, catastrophic structural failure of the hull or foundering due to a ‘rogue’ wave.”

In the case of a craft actually foundered beneath the surface, however, commercial satellite technology would be of little use.

But Glickman says if the craft is still on the surface, by knowing its dimensions and the satellite that imaged it, analysts could quickly compute how the vessel would appear from low earth orbit.

Glickman adds that because satellite images are registered with geospatial coordinates, in principle, search agencies using them should then have precise new location data to work with.

However, Clifford notes that analytical image analysis technology has to be both highly effective and fast enough to beat the clock.

And even with the best onboard signaling technology money can buy, as Clifford points out, open ocean yachting inherently carries some risk.

“The Tasman Sea is not seen as especially dangerous when compared to other deep ocean areas,” said Clifford. “But far from shore, extremes in the deep-ocean weather can pose serious risks and you are a long way from help.”

That warning resounds throughout “All is Lost.” With only a few provisions, Redford’s character is forced to set himself adrift in a standard-issue life raft. Within a week, he’s severely dehydrated, sunburned and basically starving. If anything, the film reinforces the notion that when things go badly awry on the open ocean, nature is relentlessly unforgiving.

Satellite imaging should offer hope in such cases of last resort.

“We run [some] 300 sea, air and land searches annually and satellite imagery would possibly be useful in one incident per year,” said Clifford. “That said, even for this very rare usage, we are keen to access satellite imaging’s capabilities.”

 

Images courtesy of Flickr : Nasa Goddard Flight Centre via a Creative Commons licence

*Original story: Forbes via Google News (search term: sail)