Dumbo (air-sea rescue)

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USAF Air Rescue Service Boeing SB-17G, an air-sea rescue variant of the B-17 Flying Fortress Boeing SB-17G of the 5th Rescue Squadron, Flight D.jpg
USAF Air Rescue Service Boeing SB-17G, an air-sea rescue variant of the B-17 Flying Fortress

Dumbo was the code name used by the United States Navy during the 1940s and 1950s to signify search and rescue missions, conducted in conjunction with military operations, by long-range aircraft flying over the ocean. The purpose of Dumbo missions was to rescue downed American aviators as well as seamen in distress. Dumbo aircraft were originally land-based heavy bomber aircraft converted to carry an airborne lifeboat to be dropped in the water near survivors. The name "Dumbo" came from Walt Disney's flying elephant, the main character of the animated film Dumbo , appearing in October 1941. [1]

United States Navy Naval warfare branch of the United States Armed Forces

The United States Navy (USN) is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. It is the largest and most capable navy in the world and it has been estimated that in terms of tonnage of its active battle fleet alone, it is larger than the next 13 navies combined, which includes 11 U.S. allies or partner nations. with the highest combined battle fleet tonnage and the world's largest aircraft carrier fleet, with eleven in service, and two new carriers under construction. With 319,421 personnel on active duty and 99,616 in the Ready Reserve, the Navy is the third largest of the service branches. It has 282 deployable combat vessels and more than 3,700 operational aircraft as of March 2018, making it the second largest and second most powerful air force in the world.

Search and rescue Search for and provision of aid to people who are in distress or imminent danger

Search and rescue (SAR) is the search for and provision of aid to people who are in distress or imminent danger. The general field of search and rescue includes many specialty sub-fields, typically determined by the type of terrain the search is conducted over. These include mountain rescue; ground search and rescue, including the use of search and rescue dogs; urban search and rescue in cities; combat search and rescue on the battlefield and air-sea rescue over water.

The maximal total range is the maximum distance an aircraft can fly between takeoff and landing, as limited by fuel capacity in powered aircraft, or cross-country speed and environmental conditions in unpowered aircraft. The range can be seen as the cross-country ground speed multiplied by the maximum time in the air. The fuel time limit for powered aircraft is fixed by the fuel load and rate of consumption. When all fuel is consumed, the engines stop and the aircraft will lose its propulsion.

Contents

By extension, "Dumbo" became the unofficial nickname for any air-sea rescue aircraft, including flying boats [2] that had less need to drop heavy lifeboats since the aircraft could land on the water and perform rescues directly. [3] "Dumbo" was also an unofficial nickname for any variant of the PBY Catalina patrol bomber which operated in a wide variety of roles including anti-submarine warfare against German U-boats in the Battle of the Atlantic. [4]

Air-sea rescue coordinated search and rescue (SAR) of the survivors of emergency water landings as well as people who have survived the loss of their seagoing vesse

Air-sea rescue is the coordinated search and rescue (SAR) of the survivors of emergency water landings as well as people who have survived the loss of their seagoing 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.

Flying boat aircraft equipped with a boat hull for operation from water

A flying boat is a fixed-winged seaplane with a hull, allowing it to land on water, that usually has no type of landing gear to allow operation on land. It differs from a floatplane as it uses a purpose-designed fuselage which can float, granting the aircraft buoyancy. Flying boats may be stabilized by under-wing floats or by wing-like projections from the fuselage. Flying boats were some of the largest aircraft of the first half of the 20th century, exceeded in size only by bombers developed during World War II. Their advantage lay in using water instead of expensive land-based runways, making them the basis for international airlines in the interwar period. They were also commonly used for maritime patrol and air-sea rescue.

Consolidated PBY Catalina maritime patrol and transport flying boat

The Consolidated PBY Catalina, also known as the Canso in Canadian service, is an American flying boat, and later an amphibious aircraft of the 1930s and 1940s produced by Consolidated Aircraft. It was one of the most widely used seaplanes of World War II. Catalinas served with every branch of the United States Armed Forces and in the air forces and navies of many other nations.

After the 1950s with development and greatly increased use of helicopters for air-sea rescue operations, the Dumbo aircraft were retired and the term was no longer used.

Helicopter Type of rotor craft in which lift and thrust are supplied by rotors

A helicopter is a type of rotorcraft in which lift and thrust are supplied by rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward, and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of VTOL aircraft cannot perform.

History

A USAAF Consolidated OA-10A Catalina (Army Air Forces designation of the Navy PBY) amphibious flying boat landing in waters off Keesler Field, Mississippi during a training exercise with U.S. Marine Corps rescue boat crews in 1944 PBY OA-10A off Keesler Field 1944.jpg
A USAAF Consolidated OA-10A Catalina (Army Air Forces designation of the Navy PBY) amphibious flying boat landing in waters off Keesler Field, Mississippi during a training exercise with U.S. Marine Corps rescue boat crews in 1944

Air-sea rescue by flying boat or floatplane was a method used by various nations before World War II to pick up aviators or sailors who were struggling in the water. [1] Training and weather accidents could require an aircrew to be pulled from the water, and seaplanes were occasionally used for that purpose. A limitation of flying boats and floatplanes was that if the water's surface were too rough, the aircraft would not be able to land; in those instances the most that could be done was to drop emergency supplies to the survivors.[ citation needed ]

Floatplane aircraft equipped with floats for operation from water surfaces

A floatplane is a type of seaplane, with one or more slender pontoons mounted under the fuselage to provide buoyancy. By contrast, a flying boat uses its fuselage for buoyancy. Either type of seaplane may also have landing gear suitable for land, making the vehicle an amphibious aircraft. British usage is to call "floatplanes" "seaplanes" rather than use the term "seaplane" to refer to both floatplanes and flying boats.

World War II 1939–1945 global war

World War II, also known as the Second World War, was a global war that lasted from 1939 to 1945. The vast majority of the world's countries—including all the great powers—eventually formed two opposing military alliances: the Allies and the Axis. A state of total war emerged, directly involving more than 100 million people from over 30 countries. The major participants threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. World War II was the deadliest conflict in human history, marked by 50 to 85 million fatalities, most of whom were civilians in the Soviet Union and China. It included massacres, the genocide of the Holocaust, strategic bombing, premeditated death from starvation and disease, and the only use of nuclear weapons in war.

Seaplane airplane with an undercarriage capable of operating from water surfaces

A seaplane is a powered fixed-wing aircraft capable of taking off and landing (alighting) on water. Seaplanes that can also take off and land on airfields are in a subclass called amphibious aircraft. Seaplanes and amphibians are usually divided into two categories based on their technological characteristics: floatplanes and flying boats; the latter are generally far larger and can carry far more. These aircraft were sometimes called hydroplanes, but currently this term applies instead to motor-powered watercraft that use the technique of hydrodynamic lift to skim the surface of water when running at speed.

RAF Coastal Command Vickers Warwick ASR (air-sea rescue) aircraft with a droppable airborne lifeboat under the fuselage Vickers Warwick.jpg
RAF Coastal Command Vickers Warwick ASR (air-sea rescue) aircraft with a droppable airborne lifeboat under the fuselage

The first air-dropped lifeboat was British, a 32-foot (10 m) wooden canoe-shaped model designed in 1943 by Uffa Fox to be dropped by Avro Lancaster heavy bombers for the rescue of aircrew downed in the Channel. [5] The 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 that would right itself if it landed upside down. [5] Higgins Industries, known for making landing craft (LCVPs) and PT boats, produced a 1½-ton (1400 kg), 27-foot (8 m) airborne lifeboat with two engines and waterproof internal compartments so that it would not sink if swamped or overturned. Intended to be dropped by modified Boeing B-17 Flying Fortress bombers, it was ready for production in early 1944. [6]

Uffa Fox British yacht racer

Uffa Fox, CBE was an English boat designer and sailing enthusiast.

Avro Lancaster Heavy bomber aircraft of World War II

The Avro Lancaster is a British four-engined Second World War heavy bomber. It was designed and manufactured by Avro as a contemporary of the Handley Page Halifax, both bombers having been developed to the same specification, as well as the Short Stirling, all three aircraft being four-engined heavy bombers adopted by the Royal Air Force (RAF) during the same wartime era.

Bomber Military aircraft for attack of ground targets with bombs or other heavy ordnance

A bomber is a combat aircraft designed to attack ground and naval targets by dropping air-to-ground weaponry, firing torpedoes and bullets, or deploying air-launched cruise missiles.

After wartime experiences suggested improvements, Consolidated PBY Catalina aircraft were given extra features to augment their air-sea rescue capability. One such invention was a small platform that could be braced against the side of the flying boat's hull to allow a team of two Catalina crewmen to lean out into the water and rescue a swimmer. [7]

Operations

Dumbo aircraft were sent aloft to patrol likely areas where American airmen might ditch. The Dumbo would radio the position of any survivors spotted in the water, and one or more actions could take place. [3] The Dumbo, if a flying boat configuration, could land and pick up the survivors, or it could drop emergency supplies such as a 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. [3]

Air-droppable lifeboats included the EDO A-3 lifeboat with an inboard motor, fuel, water and food; [8] or a Higgins airborne A-1 lifeboat; both required parachutes to slow their descent. As well, inflatable life rafts could be dropped without a parachute.

In the face of vigorous enemy opposition, Dumbo missions sometimes required friendly units such as fighter aircraft to suppress enemy fire during the rescue attempt. In other cases, the mere presence of an armed Dumbo aircraft was enough to keep weaker enemy forces from engaging. [1]

World War II

From the start of hostilities in World War II, air-sea rescues by flying boats were not unknown, though they were incidental to the aircraft's stated mission. 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. From January to August 1943, such rescue flights based at Guadalcanal saved 161 aviators. [9]

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. [10] 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. [10]

In the last eight months of World War II, Dumbo operations complemented simultaneous United States Army Air Forces heavy bombing operations against Japanese targets. [10] On any large-scale bombing mission carried out by Boeing B-29 Superfortresses at least three submarines were posted along the air route, with Dumbo aircraft sent to patrol the distant waters and listen for emergency radio transmissions from distressed aircraft. At the war's final B-29 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. [10]

A Navy PBM Mariner flying boat rescues Lt. (jg) J. M. Denison, shot down while operating from the escort carrier USS Marcus Island (CVE-77) in 1945 Martin PBM Mariner rescues pilot c1945.jpg
A Navy PBM Mariner flying boat rescues Lt. (jg) J. M. Denison, shot down while operating from the escort carrier USS Marcus Island (CVE-77) in 1945

Once Iwo Jima was taken by American forces, Dumbo missions had less distance to fly and could range closer to Japan, or remain on station for longer periods of time. After the Battle of Okinawa, distances were cut considerably and air-sea rescue missions observed a higher degree of success. From April to August 1945, the percentage of survivors rescued was higher than at any other point in the war. [11] Squadrons assigned Martin PBM Mariner flying boats made a significant contribution beginning in April. [11] Flying boat rescues sometimes took place while under fire from enemy shore batteries, [11] and on a few rare occasions from within an enemy-held harbor. [12]

Not all Dumbo operations were successful. Some Dumbo aircraft were lost to enemy action, weather or mechanical trouble, and some friendly fighter aircraft were shot down attempting to suppress enemy fire during a rescue. During one attempted rescue, a P-51 Mustang fighter pilot was taken prisoner by Japanese motor torpedo boats which fired at and drove away both the rescue submarine and the Dumbo aircraft. During another rescue, a fighter pilot clambered aboard the Higgins lifeboat that was dropped to him but was subsequently killed by fire from the shore of Chichijima 100 yards (90 m) away. [1]

In July 1945, a PBY Catalina Dumbo aircraft helped rescue distressed crewmen of the torpedoed cruiser USS Indianapolis. Airmen dropped rafts and supplies, but noticed that some of the more than 300 men in the water were being attacked by sharks. The pilot, Lieutenant Adrian Marks, defied regulations forbidding him to land in heavy seas and brought his flying boat to a rough landing amid 12-foot (4 m) swells. He and his crew filled the fuselage with sailors, then began using parachute cord to lash more survivors to the top of the aircraft's wing, damaging it severely. With the arrival of the destroyer USS Cecil J. Doyle, Marks and his crew were rescued along with the 56 sailors they saved. The unflyable Catalina was sunk by gunnery from the Doyle the next morning. Marks was later awarded the Air Medal for this heroic action. [13]

U.S. Coast Guard PB-1G search and rescue plane in flight, 1946 US Coast Guard PB-1G in flight.jpg
U.S. Coast Guard PB-1G search and rescue plane in flight, 1946
SB-29 "Super Dumbo", a post-World War II variant of the B-29 Superfortress, with an air-droppable EDO A-3 lifeboat rigged underneath Boeing SB-29.jpg
SB-29 "Super Dumbo", a post-World War II variant of the B-29 Superfortress, with an air-droppable EDO A-3 lifeboat rigged underneath

Korean War

After World War II, sixteen B-29 bombers were converted for air–sea rescue duty and redesignated SB-29, nicknamed "Super Dumbo". [8] The first SB-29s were received by the Air Rescue Service in February 1947. The SB-29 served through the Korean War and into the mid-1950s. [8]

Coast Guard

The United States Coast Guard operated Dumbo flights along the West Coast of the United States in the late 1940s and early 1950s with the PB-1G, a B-17 variant; eighteen B-17Gs were set aside by the USAAF in 1946 for transfer via the U.S. Navy to the Coast Guard to be used as search and rescue aircraft. [14] Such a flight is depicted briefly in the 1954 film The High and the Mighty. [15]

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Maritime patrol aircraft Military aircraft designed to reconnoiter oceans and other bodies of water

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A-3 lifeboat

The A-3 lifeboat was an airborne lifeboat developed by the EDO Corporation in 1947 for the United States Air Force (USAF) as a successor to the Higgins Industries A-1 lifeboat. The A-3 lifeboat was a key element of "Dumbo" rescue flights of the 1950s.

A-1 lifeboat

The A-1 lifeboat was a powered lifeboat that was made to be dropped by fixed-wing aircraft into water to aid in air-sea rescue operations. The sturdy airborne lifeboat was to be carried by a heavy bomber specially modified to handle the external load of the lifeboat. The A-1 lifeboat was intended to be dropped by parachute during Dumbo missions to land within reach of the survivors of an accident on the ocean, specifically airmen survivors of an emergency water landing.

Airborne lifeboat

Airborne lifeboats were powered lifeboats that were made to be dropped by fixed-wing aircraft into water to aid in air-sea rescue operations. An airborne lifeboat was to be carried by a heavy bomber specially modified to handle the external load of the lifeboat. The airborne lifeboat was intended to be dropped by parachute to land within reach of the survivors of an accident on the ocean, specifically airmen survivors of an emergency water landing. Airborne lifeboats were used during World War II by the United Kingdom and on Dumbo rescue missions by the United States from 1943 until the mid-1950s.

<i>Seenotdienst</i>

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No. 76 Wing was a Royal Australian Air Force (RAAF) wing that operated during World War II. Initially based in Far North Queensland, its headquarters transferred to Darwin, Northern Territory, in September 1944 to take control of three PBY Catalina units: Nos. 20, 42, and 43 Squadrons. The prime task of these squadrons was minelaying in the South West Pacific theatre, and they conducted these operations as far afield as Java, Borneo, the Philippines, and China. As well as minelaying, No. 76 Wing's Catalinas flew bombing, patrol, and transport missions, and dropped millions of propaganda leaflets in the closing months of the war. The wing headquarters disbanded in November 1945.

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VH-3 (Rescue squadron)

VH-3 was one of six dedicated VH rescue squadrons of the U.S. Navy during WW II. Prior to their creation, the rescue function was performed as an additional "spur of the moment" duty by regularly operating patrol squadrons. The Fleet Commanders made clear "that the men who risked their lives to rocket, bomb, and strafe the enemy wherever and whenever possible, should under no circumstances, be left to fend for themselves when disaster struck them." After the war the Japanese related that they could not understand why so much was risked to save airmen. This was a tremendous morale builder for the flyers, but there was a cold calculated logic behind this as well. It meant that very expensively trained and experienced aviators could be rescued from a watery grave or brutal captivity and put back into the fight. American aircrews captured after being shot down over the Japanese home islands faced a grim fate. VH-3 squadron members related "how intense, intense every crew member became .. over this business of saving lives", "the marvelous feeling of reward when saving a downed pilot's life", and "nose-thumbing at the Japanese military .. when we swiped near-prisoners under their eye".

VH-2 was one of six dedicated (VH) Rescue Squadrons of the U.S. Navy during World War II. A more comprehensive write-up on the VH squadrons can be found in the history of Rescue Squadron 3 (VH-3), which was the US Navy's most active VH squadron. VH-2 was established in August 1944 and disestablished in November 1945. Unlike the other VH squadrons, VH-2 mostly employed the PB2B Catalina during its wartime operations. Late in the war, the PB2B Catalina was no longer used for open sea rescues, since it had proven less rugged in the open sea than its successor the Martin PBM Mariner. Thus VH-2's primary mission was to "spot" survivors in the water and direct other craft to the site to effect the rescue. On at least two occasions, VH-2 did effect rescues with open sea landings. VH-2 was credited with the initial spotting, direct rescue, or assistance in the rescue of 96 downed bomber crewman. After the war, they were assigned the Martin PBM Mariner.

Consolidated PBY Catalina in Australian service

Developed as a naval patrol aircraft, the Consolidated PBY Catalina was a widely exported flying boat during World War II. Over the course of the conflict it served with a number of different nations in a variety of roles. In the Royal Australian Air Force, PBYs and PB2Bs served as multi role bombers and scouts, the type eventually earning great renown among Australian aircrews. The motto of the Catalina squadrons was "The First and Furthest."

References

Notes
  1. 1 2 3 4 Time, August 6, 1945. "World Battlefronts: Battle of the Seas: The Lovely Dumbos", page 1 and page 2. Retrieved on September 6, 2009.
  2. Morison, 2007, p. xxvi.
  3. 1 2 3 Algeo, John. Fifty years among the new words: a dictionary of neologisms, 1941–1991, pp. 39, 106–107. Cambridge University Press, 1993. ISBN   0-521-44971-5
  4. Owen, Gregory L. The Longest Patrol: A U-Boat Gunner's War, pp. 101, 309. iUniverse, 2006. ISBN   0-595-39113-3
  5. 1 2 Strahan, 1998, p. 193.
  6. Strahan, 1998, pp. 208–209.
  7. Popular Mechanics, December 1945. "Flying Boat Carries Rescue Platform." Retrieved on September 6, 2009.
  8. 1 2 3 National Museum of the US Air Force. Fact Sheets. Boeing SB-29 Archived October 9, 2012, at the Wayback Machine . Retrieved on September 6, 2009.
  9. Morison, 2001, pp. 332–333.
  10. 1 2 3 4 Morison, 2007, pp. 510–511.
  11. 1 2 3 Hoffman, 2004, p. 133.
  12. "Rescue at Koror", by Lieutenant Commander Fred H. Mamer.
    "One of Our Planes Is Down", by Colonel Judson H. Bell. Both stories appear within Chronolog, 1912–1954 by Craig Berry. Turner Publishing Company, 1997. ISBN   0-938021-39-7. Retrieved on September 6, 2009.
  13. The New York Times, March 15, 1998. Richard Goldstein, "Adrian Marks, 81, War Pilot Who Led Rescue of 56, Is Dead." Retrieved on September 7, 2009.
  14. United States Coast Guard Aviation History: Boeing PB-1G
  15. Hardwick, 1989, p. 66.
Bibliography