| Air-sea rescue | |
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| A Royal Navy rescue helicopter and boat in action off Falmouth, England |
Air-sea rescue (ASR or A/SR, also known as sea-air rescue or SAR[1]) is the coordinated search and rescue of the survivors of emergency water landings as well as people who have survived the loss of their sea-going vessel. ASR can involve a wide variety of resources including seaplanes, helicopters, submarines, rescue boats and ships. Specialized equipment and techniques have been developed. Military and civilian units can perform air-sea rescue.
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The first air-sea rescue was performed in August 1911 by Hugh Robinson who landed his Curtiss Aeroplane Company seaplane on Lake Michigan to pull a crashed pilot out of the water.[3] Air-sea rescue by flying boat or floatplane was a method used by various nations to pick up aviators or sailors who were struggling in the water.[4] Training and weather accidents could require an aircrew to be rescued, and seaplanes were occasionally used for that purpose. The limitation was that if the water's surface were too rough, the aircraft would not be able to land. The most that could be done was to drop emergency supplies to the survivors, or to signal surface ships or rescue boats to guide them to the correct location.
Seaplanes were the first aircraft used for air-sea rescue. Any other aircraft design had the additional danger of ditching in the water and requiring immediate rescue, but seaplanes could land on the water in an emergency and wait for rescue. Long range, endurance, and the ability to stay on station for long periods of time were seen as essential to naval aviation requirements for rescue aircraft. Robust radio equipment was necessary for contact with land and ocean surface forces.[5]
Fast, rugged, and powerful motorised lifeboats have been used to perform sea rescues since the late 19th century. These lifeboats are typically 30 to 80 feet (9 to 24 m) in length and designed to right itself if overturned. Such boats carry life-saving equipment and crew trained in first aid methods specific to sea rescue.
The principles of coordinating small surface boat rescue efforts with direction and assistance from air units were developed in the 1930s by Germany, followed by other nations in the 1940s. A wide variety of powered boats have been used for air-sea rescue, including ones such as minelayers, torpedo boats and fast attack boats that were not developed specifically for rescue.[6]
The first airborne lifeboat was British, a 32-foot (10 m) reinforced wooden canoe-shaped boat designed in 1943 by Uffa Fox to be dropped by Avro Lancaster heavy bombers for the rescue of aircrew downed in the English Channel.[7] The Mark I lifeboat's descent to the water was slowed by parachutes.
In the United States, Andrew Higgins evaluated the Fox boat and found it too weak to survive mishap in emergency operations. In November 1943, Higgins assigned engineers from his company to make a sturdier version with two engines that would right itself if it landed upside down.[7] Higgins Industries, known for making landing craft (LCVP) and PT boats, produced the A-1 lifeboat, a 1½-ton (1400 kg), 27-foot (8 m) airborne lifeboat with waterproof internal compartments so that it would not sink if swamped or overturned. Intended to be dropped by modified Boeing B-17 Flying Fortresses, it was ready for production in early 1944.[8] Later, the EDO A-3 lifeboat with an inboard motor, fuel, water and food was introduced as a replacement for the Higgins.[9] Both airborne lifeboats required parachutes to slow their descent. As well, inflatable life rafts could be dropped without a parachute.
Helicopters have taken a primary role in air-sea rescue since their introduction in the 1940s.[10] Helicopters can fly in rougher weather than fixed-wing aircraft, and they can deliver injured passengers directly to hospitals or other emergency facilities. Helicopters can hover above the scene of an accident while fixed-wing aircraft must circle, or for seaplanes, land and taxi toward the accident. Helicopters can save those stranded among rocks and reefs, where seaplanes are unable to go. Landing facilities for helicopters can be much smaller and cruder than for fixed-wing aircraft. Additionally, the same helicopter that is capable of air-sea rescue can take part in a wide variety of other operations including those on land. Disadvantages include the loud noise causing difficulties in communicating with the survivors and the strong downdraft that the hovering helicopter creates which increases wind chill danger for already-soaked and hypothermic patients.[11] Helicopters also tend to have limited range and endurance.
The United States Coast Guard (USCG) was the first agency to evaluate the potential of helicopter rescue assistance, beginning in 1938.[12] Two early Sikorsky R-4s were acquired in 1941, and training was initiated at Coast Guard Station Brooklyn in New York.[12] In 1942, Royal Air Force and Royal Navy fliers trained in Brooklyn after which the British bought a large number of "hoverflies" from Sikorsky to re-organize 705 Naval Air Squadron.[12] The first helicopter air-sea rescue was carried out in 1946 when a Sikorsky S-51 being demonstrated to the U.S. Navy was used in an emergency to pull a downed Navy pilot from the ocean.[13]
The first peace-time air-sea rescue squadron exclusively using helicopters was No. 275 Squadron RAF re-organized in 1953 at Linton-on-Ouse.[12] The unit painted their Bristol Sycamore aircraft all yellow, with lettering on the side reading "RESCUE"—a paint scheme that has continued to the present.[12]
In the 1950s, some models of helicopter such as the Bell 47 and 48 were fitted with pontoons so that they could rest on both water and land.[14] Other helicopters such as the Sea King and the Seaguard were made with a water-resistant hull which allowed them to settle directly onto the water for long enough to effect a rescue.[15] Such amphibious helicopters came to the fore in the 1960s but have been largely replaced by helicopters unable to land on water, due to high aircraft development costs.[15] Amphibious helicopters paid dividends for rescue personnel who enjoyed greater safety and success during operations.[15] Operations that use non-amphibious helicopters rely to a higher degree on hoists, rescue baskets, and rescue swimmers.[15]
Rescue swimmers have been used for air-sea rescue work to assist in picking up survivors who are not able to reach the rescue craft, especially those incapacitated by exposure to cold water.[16] Since the mid-1980s when standards were set down for their instruction and implementation, rescue swimmers have deployed from rescue helicopters or rescue boats and have been trained to extricate downed airmen from fouled parachute lines and ejection seats.[16] Rescue swimmers must meet a number of difficult requirements: their physical conditioning must be kept at a high level, they must be expert in first aid treatment methods, and they are often highly trained technicians crucial to the operation of the rescue craft.[17]
Air-sea rescue operations carried out during war can save valuable trained and experienced airmen.[18] Moreover, the knowledge that such operations are being carried out can greatly enhance the morale of the combat aircrew faced not only with the expected hostile reaction of the enemy but with the possible danger of aircraft malfunction during long overwater flights.[18]
Dedicated air-sea rescue units were not organized by any nation during World War I. Some rescues were performed, however, by individuals and groups acting on their own initiative. Near the end of the Adriatic Campaign, United States Navy Reserve pilot Ensign Charles Hammann flew his U.S. Navy seaplane to land on the Adriatic Sea near Pula and rescue a fellow aviator who had been shot down by enemy action. Hamman's aircraft was only designed to hold one person, the pilot, but, under the constant threat of enemy fire, he was able to complete the rescue and land at his base at Port Corsini in Italy. Hamman received the Medal of Honor for this action.[19]
In 1935, Lieutenant Colonel Konrad Goltz of the German Air Force (Luftwaffe), a supply officer based at the port of Kiel, was given the task of organizing the Seenotdienst (Sea Rescue Service), an air-sea rescue organization focusing on the North Sea and the Baltic Sea. Goltz gained coordination with aircraft units of the Kriegsmarine as well as with civilian lifeboat societies.[6] Early in 1939, with the growing probability of war against Great Britain, the Luftwaffe carried out large-scale rescue exercises over water. Land-based German bombers used for search duties proved inadequate in range, so bomber air bases were constructed along the coast to facilitate an air net over the Baltic and North seas.[6] Following this, the Luftwaffe determined to procure a purpose-built air-sea rescue seaplane, choosing the Heinkel He 59, a twin-engine biplane with pontoons. A total of 14 He 59s were sent to be fitted with first aid equipment, electrically heated sleeping bags, artificial respiration equipment, a floor hatch with a telescoping ladder to reach the water, a hoist, signaling devices, and lockers to hold all the gear.[6]
The United States Coast Guard acquired its first seaplanes in 1925 at Air Station Gloucester, and used them for coastal patrol as well as single, uncoordinated air rescue units. The air complement grew in the 1930s with the establishment of Air Station Salem and in the 1940s with the first formation of a dedicated U.S. domestic air-sea rescue service on the East Coast in 1944 at Salem.[20]
In May 1940, USCG Commander William J. Kossler witnessed a helicopter demonstration flight by Igor Sikorsky, flying the Vought-Sikorsky VS-300.[21] By 1941, Sikorsky had equipped the helicopter with pontoons for water landings. Kossler saw at once the advantages of helicopter operations, and began to plan for helicopter-equipped search and rescue squadrons. In June 1942, USCG Lieutenant Commander F. A. Erickson proposed both submarine hunting and air-sea rescue duties for helicopters and in July, the U.S. Bureau of Aeronautics called for four Sikorsky helicopters to be studied by the U.S. Navy and the Coast Guard.[21] The first USCG helicopter detachment was formed in mid-1943. In the following years, various makes and models of helicopter were obtained, including the Sikorsky HUS-1 Seahorse in 1956 and the HH-52A Seaguard in 1962. The Seaguard was amphibious—it allowed both land and water landings.[21]
In 1965, the USCG ordered the Sikorsky S-61R, designated HH-3F Sea King, or Pelican. The Pelican was an amphibious helicopter which featured a powerful search radar protected within a radome protruding from the left side of the nose.[22] In 1985, the Pelican was phased out in favor of the HH-65 Dolphin, a helicopter developed by Aérospatiale's Eurocopter division, based on their popular Dauphin model.
Today, the USCG reports that 95% of its marine rescues are conducted within 20 miles (32 km) of the shore, and that 90% are purely rescue, as emergency beacons and other information frequently guide the rescuers directly to the location. The cost of searching is high: the other 10% of rescues, the ones requiring an extensive search, cost the Coast Guard $50 million each year.[23]
The first multiple air-sea rescue operation occurred on December 18, 1939.[6] A group of 24 British Vickers Wellington medium bombers were frustrated by low clouds and fog in their mission to bomb Wilhelmshaven, and they turned for home. The formation attracted the energetic attention of Luftwaffe pilots flying Bf 109 fighter aircraft as well as Bf 110 heavy fighters, and more than half of the Wellingtons went down in the North Sea. German Seenotdienst rescue boats based at Hörnum worked with He 59s to save some twenty British airmen from the icy water.[6]
In 1940, the Seenotdienst added bases in Denmark, Holland and France. The Heinkel He 59s were painted white in June, with red crosses to indicate emergency services.[24] A few French seaplanes were modified for rescue and attached to the organization. In response to the heavy toll of German air action against Great Britain, Adolf Galland recommended that German pilots in trouble over the ocean make an emergency water landing in their aircraft instead of bailing out and parachuting down. The aircraft each carried an inflatable rubber raft which would help the airmen avoid hypothermia from continued immersion in the cold water, and increase the time available for rescue. British fighters such the Supermarine Spitfire and the Hawker Hurricane did not carry inflatable rafts, only lifejackets which were little help against the cold.[6]
In July 1940, a white-painted He 59 operating near Deal, Kent was shot down and the crew taken captive because it was sharing the air with 12 Bf 109 fighters and because the British were wary of Luftwaffe aircraft dropping spies and saboteurs.[6] The German pilot's log showed that he had noted the position and direction of British convoys—British officials determined that this constituted military reconnaissance, not rescue work. The Air Ministry issued Bulletin 1254 indicating that all enemy air-sea rescue aircraft were to be destroyed if encountered. Winston Churchill later wrote "We did not recognise this means of rescuing enemy pilots who had been shot down in action, in order that they might come and bomb our civil population again."[25] Germany protested this order on the grounds that rescue aircraft were part of the Geneva Convention agreement stipulating that belligerents must respect each other's "mobile sanitary formations" such as field ambulances and hospital ships.[6] Churchill argued that rescue aircraft were not anticipated by the treaty, and were not covered.[6] British attacks on He 59s increased. The Seenotdienst ordered the rescue aircraft armed[24] as well as painted in the camouflage scheme of their area of operation. Rescue flights were to be protected by fighter aircraft when possible.
In October 1940, yellow-painted Sea Rescue Floats were placed by the Germans in waters where air emergencies were likely. The highly visible buoy-type floats held emergency equipment including food, water, blankets and dry clothing, and they attracted distressed airmen from both sides of the war. Both German and British rescue units checked the floats from time to time, picking up any airmen they found, though enemy airmen were immediately made prisoner of war.[6]
During the first two years of war, the British had no coordinated air-sea rescue units—only about 28 crash boats and no dedicated aircraft.[6] The ditching of a British aeroplane in the Channel or the North Sea usually doomed its crew.[6] The fate of downed airmen was primarily in the hands of their parent organization, and they had little they could do to help the crash boats locate the accident site. In January 1941, a Directorate of Air-Sea Rescue was formed by the Royal Air Force for the purpose of saving those in distress at sea, especially airmen. Proper provisioning of rescue squadrons was slow, and it took more than a year for sea-going rescue boats and aircraft to come together in active ASR squadrons.[26] The organization copied much from the successful efforts of the Seenotdienst.[6] British air-sea rescue units began in September 1942 to work with the United States Army Air Forces to coordinate rescue activities over the Channel and the North Sea. The combined US-UK effort led to the saving of nearly 5,000 American fliers.[6]
In the Pacific Ocean theater, the first purposely assigned rescue aircraft, a PBY Catalina, was given the mission of plucking downed airmen from the ocean in January 1943. From January to August, such rescue flights based at Guadalcanal saved 161 aviators.[27]
Beginning in November 1943, during the Gilbert and Marshall Islands campaign, American submarines were tasked with the rescue of U.S. Navy and Marine airmen downed during aircraft carrier attack operations.[28] Submarines were often vectored to a rescue site by aircraft providing coordinates, but too many layers of command slowed the cooperation considerably. Long-range naval patrol aircraft were fitted with extra radio equipment to allow direct contact with surface and underwater units. By the end of 1944, some 224 airmen had been rescued by submarine.[28]
Dumbo aircraft, converted land-based heavy bombers named after Walt Disney's animated flying elephant,[4] were sent aloft in the Pacific War to patrol likely areas where American airmen might ditch. The Dumbo would radio the position of any survivors spotted in the water, and it would drop emergency supplies such as an airborne lifeboat, by parachute. A nearby ship or submarine could be requested to come rescue the survivors, or an air-sea rescue station could be signaled to send a rescue boat or flying boat.[29]
In the last eight months of World War II, Dumbo operations complemented simultaneous United States Army Air Forces heavy bombing operations against Japanese targets. [28] On any one large-scale bombing mission carried out by Boeing B-29 Superfortresses, at least three submarines were posted along the air route, and Dumbo aircraft sent to patrol the distant waters, and listen for emergency radio transmissions from distressed aircraft. At the final bombing mission on August 14, 1945, 9 land-based Dumbos and 21 flying boats covered a surface and sub-surface force of 14 submarines and 5 rescue ships.[28]
Toward the end of World War II, several B-29 bombers on each large-scale bombing mission were emptied of ammunition, filled with rescue supplies and rotated through Super Dumbo patrol duty as their squadron mates lumbered off filled with bombs. Following that conflict, 16 B-29 bombers were converted to full-time air–sea rescue duty and redesignated SB-29 Super Dumbo.[9] The SB-29 served throughout the Korean War and into the mid-1950s.[9] The SB-17 began serving in Korea, but dropped only a few lifeboats to save several lives before being phased out in late 1951—there were enough SB-29 Super Dumbos and Grumman SA-16A Albatross flying boats to satisfy the need.[18]
Other air-sea rescue aircraft used in the Sea of Japan and the Yellow Sea include the PB-1G land-based maritime patrol bomber and the Sikorsky H-5 helicopter, and later the H-19.[30] Rafts were often dropped which inflated upon impact with the water. Operating in coordination with the U.S. Navy, the USCG painted their air-sea rescue assets white.[31]
Shortly after the Korean War, some Douglas C-54 Skymasters were converted to air-sea rescue work and redesignated SC-54, replacing all the Flying Fortresses and Super Fortresses still in service. The SC-54 sometimes carried an airborne lifeboat and could carry more rescue supplies over longer distances.[18]
In the Vietnam War, American naval vessels and aircraft from both the U.S. Navy and the U.S. Air Force participated in air-sea rescue patrols in the Gulf of Tonkin. The helicopter most closely associated with long-range U.S. air-sea rescue operations in Southeast Asia was the Sikorsky S-61R, called the "Pelican" or "Jolly Green Giant", a variation of the SH-3 Sea King. First acquired by the U.S. Navy in 1961 for anti-submarine warfare, variants of the helicopter were quickly utilized for many duties including rescue, and were operated as well by the United States Air Force (USAF) which developed an in-flight refueling system. In 1970, USAF Air Rescue and Recovery Service (ARRS) Sea Kings flew from the U.S. to France using such refueling methods.[32] At the same time as the Vietnam War, U.S. Navy helicopters were used during the Apollo space missions to pull astronauts and their capsules from the ocean.[32]
Sixteen Westland Sea King SAR helicopters were in operation with the Royal Navy at the time of the 1982 Falklands War. SAR helicopters were assigned search and rescue patrols, and Sea King as well as Westland Wessex aircraft plucked several airmen from the icy waters.[33] Helicopters were also used to transport troops and to rescue Special Air Service (SAS) troops trapped on a glacier in heavy wind and snow conditions.[33]
Two Royal Air Force SAR helicopters of No. 1564 Flight on detached duty continue to provide cover for the Falkland Islands.[34]
The New York Police Department has operated a coordinated air-sea rescue program out of Floyd Bennett Field since 1986 when scuba divers were stationed in shifts at a hangar containing helicopter rescue aircraft.[35] The NYPD Aviation Unit operates night vision-equipped Bell 412 helicopters which fly to rescue locations carrying two pilots, one crew chief and two scuba divers. NYPD motor lifeboats from the Harbor Unit respond as well, meeting the helicopter at the incident site to pick up non-critically injured survivors who don't require air evacuation. After the January 2009 ditching of US Airways Flight 1549 in the Hudson River, NYPD air-sea rescue units pulled two survivors from the icy river and applied first aid for hypothermia,[36] and divers swam through the submerged aircraft cabin to make certain all passengers were evacuated.[37]