Sunday, April 1, 2007
Search and Rescue: One Day in Hell
In the midst of a typhoon,Hong Kong’s Government Flying Service pulled 91 people from raging seas in rescues that tested the capacity of its helicopters and the mettle of their crews.
AUG. 3, 2006 ALMOST SEEMED LIKE AN ORDINARY DAY AT the Government Flying Service base at Hong Kong International Airport on Chek Lap Kok Island. One pilot, Capt. West Wu, was in a meeting. Another, Capt. Eric Leung, was doing paperwork.
But Typhoon Prapiroon loomed about 100 nm (185 km) to the south-southwest and was moving north and west. Soon enough, its effects were felt. Within 20 hr, the service’s crews would rescue 91 people from raging seas.
At 1018 local, the siren sounded for a long-range search-and-rescue mission. Wu excused himself from the meeting. Leung hit "send" on the e-mail he’d just finished. Both rushed to the Air Command and Control Center.
The call was to evacuate 23 seamen from a disabled vessel, the Wing On IV, that had run aground and was taking on water about 90 nm (167 km) southwest of Hong Kong, very close to Prapiroon’s track.
Ground crews checked out the fixed-wing Jetstream 41 turboprop and the Eurocopter AS332-L2 Super Puma and loaded SAR equipment. On the ramp, winds were gusting to 43 kt and the rain was heavy.
With limited information, Leung boarded the J41 with his crew — Keith Kwong, Ken Wong, and K.H. Ng — and headed for the vessel. The weather had grounded a lot of the commercial airliners at the airport, but the J41 crew had to brave the wind and rain. Their role was to be first on scene, locate the vessel, and lead the helicopter to it. They launched at 1049. The Super Puma took off at 1051, with Wu and Capt. Dickens Lam in the cockpit and Winch Operator Edward Li and Winchman Jason Chan in the cabin.
The weather deteriorated en route. The crews encountered fierce turbulence, wind shear, rain, and winds up to 85-95 kt (160-175 km/hr), with their severity increasing as the aircraft approached the typhoon’s track.
On scene, the J41 found the rescue helicopter was not responding to radio calls. Back at the command center, everyone was scrambling to locate the Super Puma. But there was an uneasy silence.
After some 15 min, Leung in the J41 heard a transmission — "Conducting winching, standby." It was Lam, the AS332 copilot.
On scene, winds gusted to 97 kt (180 km/hr). Visibility was less than 1/3-mi (0.5 km). Seas were very rough, with waves nearly 40 ft (10 m). The helicopter spotted the vessel. Her hull was on rocks, her bow pitching with the waves. A cliff was close in, and the superstructure and rigging made rescue difficult.
Unaware some radio transmissions hadn’t gotten through, the crew proceeded, opting for a "high-line" rescue. Li, the winch operator, lowered Chan onto the deck to assist survivors with the double-strop method. To do this, Li had to lean out. The rain pounded him; he could hardly keep his eyes open at times.
Chan’s cable became entangled in the rigging as the ship was tossed by the waves. A misstep then could drop him to the deck, or worse, into the raging water. But he disentangled himself and made it to the deck.
Steadying himself against the wind on the slippery deck of the rocking vessel, he assisted the survivors in putting the strop on and they were hoisted in pairs. After each transfer, Chan had to fight his way on that deck to retrieve the strop for the next pair.
In the aircraft, Li had to control the swing of the cable as the survivors were hoisted. After a total of 12 transfers, Li and Chan were simply exhausted. Chan was the last to be hoisted up.
With Chan on board and the door closed, Wu headed the Super Puma back toward Hong Kong. The weather had worsened, there were 23 more lives in his hands, and there was less fuel. The helicopter was blown off course by extreme crosswinds and was flying on the typhoon’s edge most of the time. Its turbulence created up- and downdrafts of 1,000 fpm (300 m/min).
With the help of civilian air traffic controllers, Wu found the shortest route back to base and stayed away from high terrain.
The helicopter finally touched down at 1350. The return flight from the scene, which takes 45 min on an ordinary day, took 75 min.
While the command center anxiously awaited the return of Wu’s ship, it received another call. Sixty-eight crewmembers were on the barge Hai Yang Shi You 298. Returning from an oil rig, it had activated its emergency beacon 71 nm (132 km) southwest of Hong Kong.
The J41 was diverted to search for the barge. On the ramp at Chek Lap Kok, ground crews readied a second Super Puma for the mission. The three AS332-l2 are the service’s long-range rescue fleet. They are fitted with search radar, forward-looking infrared, a TV camera and an auto-hover/letdown system.
Having three helicopters means two are always available, allowing for maintenance.
At the command center, Capt. Michael Chan and his crew — copilot James Yuen, Winch Operator Kenny Cheng, and Winchman Jack Chak — boarded the helicopter. The weather then was very poor. Winds were gusting at 54 kt (100 km/hr) and visibility was less than 3/4 mi (1 km). They had to make an instrument departure, uncommon for helicopter takeoffs and particularly demanding. En route, the crew also faced high winds, heavy rains, and near-zero visibility.
"Radar use did not work," said Chan, who attended this year’s Heli-Expo. "It was all red on my radar screen."
The helicopter reached the scene after a hard battle of 40 min and made contact with the J41. They spotted the barge quickly; it was pitching up to 45 deg and rolling violently, pounded by 70-ft (21-m) waves.
After assessing the situation carefully, the crew agreed to lower Chak to its helideck. But Cheng couldn’t open the door. Chan checked his instruments; the airspeed indicator read 72 kt (133 km/hr).
"That is quite unusual," he said, "for an aircraft sitting in a hover."
He repositioned the aircraft and Cheng opened the door. Chak stepped into the ripping wind and Cheng lowered him to the deck, quietly promising himself he would retrieve Chak unharmed.
Once on the deck, Chak immediately had to lie flat lest he be thrown overboard as the barge pitched. On the helideck there was nothing to hold on to.
This crew also used the "high-line" method, lifting survivors in pairs in quick succession. There were several times when the returning strop landed far from Chak, who had to crawl to the deck’s edge and drag it and the 20-lb (9-kg) weight attached to it back to the helideck.
"Sitting in the hover at the rear end of the barge," Chan, the aircraft commander, said, "at times I was unable to see the bow because of the heavy rain."
Cheng and Chak continued hoisting until there was no more room; 28 survivors were on board. Chan called an end to the mission. Seeing the disappointment of the remaining survivors and knowing a second helicopter was on its way, Chak shouted, "We will see each other in Hong Kong," and gave them a thumbs-up signal. Chan flew on instruments on the return, cutting through extremely heavy rain and violent turbulence. "I flew the slowest instrument landing of my life — 30 kt on the ILS," he said.
Capt. Cody Wong reported for duty at 1310, well aware he would be launched because one helicopter could not pick up all 68 survivors.
The wind remained at 45-65 kt (80 – 120 km/hr) and visibility was still less than 3/4 mi (1 km). The rain was so heavy that Cody and his crew — Capt. Bruce Wong, Ivan Chan, and Mason Ng — had to wait in the helicopter for 30 min. before they could take off.
The wind and rain on scene had relented slightly, but the sea was still very rough.
The crew had the advantage of having better information on the situation and hence were able to effect the rescues relatively quickly. In the midst of the operation, the rain was so heavy that they had to stop hoisting temporarily.
After taking in 28 survivors, that crew also had to return to base.
At the command center, running out of daylight and facing worsening weather, the controller (or commander) of the service, Capt. Brian Butt, had to make the difficult decision that another rescue mission that day was unacceptably risky.
Rescues would continue at first light on the next day, when Capt. Ardis Tang and his crew — Capt. Bowie Fung, Benny Chan, and Stanley Lam — reported for duty.
Ardis humbly described the rescue as uneventful compared with the previous ones.
In fact, he and his crew still faced heavy rain, strong winds, and low visibility. They successfully recovered the last 12 survivors, who were battered and very seasick, but overjoyed at finally being taken to safety.