Skip bombing

Skip bombing was a low-level bombing technique independently developed by several of the combatant nations in World War II, notably Australia, Britain, and the United States. It allows an aircraft to successfully attack shipping by skipping the bomb across the water like a stone. Dropped at very low altitudes, the bomb never rises more than about 5 metres (16 ft) above the surface of the water, ensuring that it will hit the side of the ship as long as it is aimed correctly in direction.

As the technique required the aircraft to fly at very low altitudes directly at the ship, it made the task of shooting down the aircraft easier as well. In the immediate pre-war era, there was considerable effort to develop new bombsights that would allow the aircraft to remain at higher altitudes. The most notable was the US Navy's Norden bombsight, which was fit to most Navy aircraft. In practice, these proved largely useless, and the skip-bombing technique was soon introduced operationally.

After Pearl Harbor (December 1941), it was used prominently against Imperial Japanese Navy warships and transports by Major William Benn of the 63rd Squadron, 43rd Bomb Group (Heavy), Fifth Air Force, United States Army Air Forces in the Southwest Pacific area theater during World War II. General George Kenney has been credited with being the first to use skip bombing with the U.S. Army Air Forces.[1][2]

A20BismarckSea
U.S. A-20 Havoc of the 89th Squadron, 3rd Attack Group, at the moment it clears a Japanese merchant ship following a successful skip bombing attack. Wewak, New Guinea, March 1944

Technique

The bombing aircraft flew at very low altitudes (200–250 ft (61–76 m)) at speeds from 200–250 mph (320–400 km/h; 170–220 kn). They would release a "stick" of two to four bombs, usually 500 lb (230 kg) or 1,000 lb (450 kg) bombs preferably equipped with four- to five-second time delay fuzes. The bombs would "skip" over the surface of the water in a manner similar to stone skipping and either bounce into the side of the ship and detonate, submerge and explode next to the ship, or bounce over the target and miss. Unlike "Upkeep" or "Highball", this technique used standard bomb types, although only bombs with a generally hemispherical nose—as all regular American World War II "general purpose" aircraft bomb ordnance items were designed to have—would bounce off the water surface properly.

A similar technique was mast-height bombing, in which bombers would approach the target at low altitude, 200 to 500 feet (61 to 152 m), at about 265 to 275 miles per hour (426 to 443 km/h), and then drop down to mast height, 10 to 15 feet (3.0 to 4.6 m) at about 600 yards (550 m) from the target. They would release their bombs at around 300 yards (270 m), aiming directly at the side of the ship. In practice, the techniques were often combined: a bomber would drop two bombs, skipping the first and launching the second at mast height.[3] The Battle of the Bismarck Sea would demonstrate the effectiveness of these low-level attacks on ships.[4] Practice missions were carried out against the SS Pruth, a liner that had run aground in 1923.[5]

Aircraft

Various aircraft types were used for skip-bombing attacks, including B-17 Flying Fortress heavy bombers, B-25 Mitchell medium bombers, and A-20 Havoc attack bombers. These were supported by heavily armed Royal Australian Air Force Bristol Beaufighters, which would suppress Japanese antiaircraft fire with their machine guns and cannon. The Soviets used lend-leased A-20 Havocs and P-40 Tomahawks as well as Il-2 Sturmoviks (also used for air defence suppression). Skip bombers were often used by aviation of the Soviet Northern Fleet in combination with torpedo bombers (usually the same A-20 aircraft, skip bomber and torpedo bomber operated in pairs). Skip bombers were called "topmachtoviks" (топмачтовики) in Russian, because they were flying "at the level of ship mast tops".

Advantages and disadvantages

Skip bombing carried several advantages. Unguided, unpowered bombs are vastly cheaper than torpedoes of equivalent explosive power. Torpedoes take up to several minutes to reach their targets after launch, enough time for an agile ship with an attentive crew to turn and avoid the attack or minimize its damage; skipped bombs, however, reach their targets in seconds. Skip bombing is additionally carried out at high speeds, increasing bombers' chances of surviving anti-aircraft fire as aerial torpedoes of the era were dropped at relatively low speeds.

The main drawback of skip bombing was that it took a great deal of skill to perfect; sometimes the bombs would detonate too soon, or in some cases, sink too deep before its delay-fuzed explosion.[6]

History

The first use of low-altitude bombing in WWII properly belongs to the British. On September 4, 1939, 15 British Bristol Blenheim bombers assaulted a group of German vessels near Wilhelmshaven, Germany. From an altitude of 100 feet, the aircraft crews dropped their bombs straight onto the decks of the ships—not skipped them up to or into the hulls. These first efforts failed to sink the ships because the bombs had insufficient time to arm before impact. They did, however, demonstrate the precision of a low-altitude attack. The British continued to use low-altitude techniques and eventually began to incorporate skip bombing into their tactics.[7]

Although historically, American skip bombing started with the prewar attack doctrine espoused by General George Kenney,[8] practically, it began on August 26, 1941, when General Henry "Hap" Arnold, Chief of the Army Air Forces (US), heard details of a British skip bombing attack at an Allied conference in England.[9] Upon his return from England, General Arnold charged developmental teams at Eglin Army Airfield, Florida with the task of creating an American version of skip bombing.[10]

Major William Benn, General Kenney's aide, had witnessed some of the testing at Eglin during the summer of 1942. In July of that year, Kenney and Benn conducted their own ad hoc experiment in Nadi, Fiji on Kenney's way to take command of the Fifth Army Air Force based in Australia.[11] In late September 1942, Major Benn, then commanding the 63d BS of the 43d Bombardment Group, was using a wrecked ship, SS Pruth, sitting on a reef outside Port Moresby Harbor for skip bombing training.[12][13]

By the time the Eglin Airfield test results were released in December 1942, Benn and the 63d BS, 43d BG, Fifth Army Air Force had already put low-altitude and skip bombing into practice. The first time skip bombing was used in action by U.S. pilots was against Japanese warships at Rabaul on New Britain on the night of October 22–23, 1942, where B-17 heavy bombers attacked and destroyed the enemy vessels.[14] With the continuing success against shipping in Rabaul Harbor throughout October and November 1942, both the tactic and the term 'skip bombing' had become popular in the Fifth Army Air Force.[15]

A notable use of this technique was during the Battle of the Bismarck Sea, March 2–4, 1943, off the northern coast of New Guinea.

See also

References

Citations

  1. ^ Kuhn, Tom (April 1998). "Ideas That Lift the Air Force". Airman. 42 (4): 8–9. Archived from the original on July 15, 2006. Retrieved October 28, 2012.
  2. ^ "Biographies : General George Churchill Kenney". United States Air Force. Archived from the original on 2012-07-17. Retrieved October 28, 2012.
  3. ^ Rodman 2005, p. 61
  4. ^ Rodman 2005, p. 68
  5. ^ McAulay 1991, p. 20
  6. ^ Dr. Carlson, Florida Gulf Coast University.
  7. ^ Rodman 2005, p. 36
  8. ^ Rodman 2005, p. 39
  9. ^ Rodman 2005, p. 36
  10. ^ Rodman 2005, p. 37
  11. ^ Kenney 1949, p. 22
  12. ^ Rodman 2005, p. 38
  13. ^ Kenney 1949, p. 105
  14. ^ Kenney 1949, p. 127
  15. ^ Rodman 2005, p. 39

Bibliography

External links

3rd Operations Group

The 3rd Operations Group is the operational flying component of the United States Air Force 3rd Wing. It is stationed at Elmendorf Air Force Base, Alaska, and is assigned to Pacific Air Forces' Eleventh Air Force.

The group is a composite organization that provides air superiority and defense for Alaska flying F-22A Raptor stealth aircraft. In addition, the group supports Pacific Air Forces in the Pacific Command area of responsibility flying C-17 Globemaster III transports and E-3B sentry airborne early warning and control (AWACS) aircraft.

The group is a direct successor organization of the 3rd Attack Group, one of the 15 original combat air groups formed by the Army before World War II. It is the oldest active group in the USAF, and the first created after the establishment of the U.S. Air Service. Based in Texas after World War I, the group patrolled the Mexican Border from Brownsville, Texas, to Nogales, Arizona. The group pioneered dive bombing, skip-bombing, and parafrag attacks in the 1920s—the earliest forms of precision guided attack from aircraft—and put this work to good use in World War II.

The World War II 3rd Bombardment Group moved to Australia early in 1942 and served primarily in the Southwest Pacific Theater as a light bombardment group assigned to Fifth Air Force. The group participated in numerous campaigns during the war, engaging in combat over Japan; Netherlands East Indies; New Guinea; Bismarck Archipelago; Western Pacific; Leyte; Luzon and the Southern Philippines. On 2 November 1943, the group encountered heavy opposition from Japanese forces at Simpson Harbor, New Britain. In that attack Major Raymond H. Wilkins, commander of the 8th Bombardment Squadron, sank two ships before he was shot down as he deliberately drew the fire of a destroyer so that other planes of his squadron could withdraw safely-an action for which Maj Wilkins was posthumously awarded the Medal of Honor.

The 3rd again served in combat during the Korean War, using B-26 Invader light bombers. Captain John S. Walmsley, Jr. was posthumously awarded the Medal of Honor for his actions a night mission. Capt Walmsley discovered and attacked an enemy supply train, and after exhausting his ammunition he flew at low altitude to direct other aircraft to the same objective; the train was destroyed but Walmsley’s plane crashed in the target area.

Notable alumni include General Hoyt S. Vandenberg, General Jimmy Doolittle, General Lewis Brereton, General Richard Ellis, General John Henebry, Major Paul I. "Pappy" Gunn, and General Nathan Twining.

42nd Air Base Wing

The 42nd Air Base Wing is a United States Air Force unit assigned to Air University of Air Education and Training Command. It is stationed at Maxwell-Gunter Air Force Base, Alabama and is the host unit for Maxwell-Gunter. The wing's primary mission is to support all activities of Air University, the 908th Airlift Wing and other tenant units stationed at Maxwell-Gunter.

The wing was first activated shortly before the beginning of World War II as the 42nd Bombardment Group, a medium bomber unit. It conducted antisubmarine patrols off the Pacific coast following the Japanese attack on Pearl Harbor. The group provided units to reinforce the defenses of Alaska and to conduct patrols against German U-boats in the Caribbean Sea. It was brought up to strength by the transfer of veteran squadrons in 1943 when it moved to the Southwest Pacific Theater as part of Thirteenth Air Force. The 42nd saw combat in the Solomon Islands, Russell Islands, New Guinea and the Philippines. The group was awarded a Distinguished Unit Citation for its pre-invasion bombing of Balikpapan from 23 to 30 June 1945. Its missions during the campaign in the Philippines earned it a Philippine Presidential Unit Citation. The 42nd was inactivated in Japan in the spring of 1946 after serving as part of the occupation forces there.

The 42nd Bombardment Wing was initially activated in 1953 with Convair B-36 Peacemakers as a component of Strategic Air Command's heavy bomber force. After two years flying the Peacemaker, it became the second wing to fly the Boeing B-52 Stratofortress, and the first to convert to the B-52 from propeller-driven bombers. The wing maintained half of its planes on alert throughout the Cold War, and increased its alert commitment for the Lebanon crisis of 1958 and the Cuban Missile Crisis. The wing also provided aircraft and crews for the Vietnam War and First Gulf War. The wing was consolidated with the group into a single unit in 1985. The consolidated unit was inactivated when its home station, Loring Air Force Base, closed in 1994.

The wing was activated several months later as 42nd Air Base Wing, replacing the 502nd Air Base Wing as the host organization for Maxwell Air Force Base (now Maxwell-Gunter Air Force Base), Alabama. It has supported all Air Force units in the Montgomery, Alabama region since that time.

43rd Air Mobility Operations Group

The 43d Air Mobility Operations Group is an active duty air mobility unit at Pope Field, Fort Bragg, North Carolina (formerly Pope AFB), and is part of the Air Mobility Command (AMC) USAF Expeditionary Center. The unit is composed of five squadrons, including one of the only two active Air Force aeromedical evacuation squadrons based in the United States. The group's primary mission focuses on providing enroute operations and enabling global response and airborne support for Fort Bragg's 82nd Airborne Division.

The 43d Operations Group was redesignated the 43d Airlift Group on 1 March 2011 after the inactivation of the 43d Airlift Wing. It was later redesignated the 43d Air Mobility Operations Group on 14 June 2016.

89th Tactical Missile Squadron

The 89th Tactical Missile Squadron is an inactive United States Air Force unit. Its last assignment was with the 38th Tactical Missile Wing, based at Pydna Missile Base at Wüschheim Air Station, West Germany. It was inactivated on 22 August 1990.

Alberto A. Nido

Brigadier General Alberto A. Nido (1 March 1919 – 27 October 1991) is a former United States Air Force officer who during World War II served in the Royal Canadian Air Force, the British Royal Air Force and in the United States Army Air Forces. He was also the co-founder of the Puerto Rico Air National Guard.

Boeing B-17 Flying Fortress

The Boeing B-17 Flying Fortress is a four-engined heavy bomber developed in the 1930s for the United States Army Air Corps (USAAC). Competing against Douglas and Martin for a contract to build 200 bombers, the Boeing entry (prototype Model 299/XB-17) outperformed both competitors and exceeded the air corps' performance specifications. Although Boeing lost the contract (to the Douglas B-18 Bolo) because the prototype crashed, the air corps ordered 13 more B-17s for further evaluation. From its introduction in 1938, the B-17 Flying Fortress evolved through numerous design advances, becoming the third-most produced bomber of all time, behind the four-engined B-24 and the multirole, twin-engined Ju 88.

The B-17 was primarily employed by the USAAF in the daylight strategic bombing campaign of World War II against German industrial and military targets. The United States Eighth Air Force, based at many airfields in central, eastern and southern England, and the Fifteenth Air Force, based in Italy, complemented the RAF Bomber Command's nighttime area bombing in the Combined Bomber Offensive to help secure air superiority over the cities, factories and battlefields of Western Europe in preparation for the invasion of France in 1944. The B-17 also participated to a lesser extent in the War in the Pacific, early in World War II, where it conducted raids against Japanese shipping and airfields.From its prewar inception, the USAAC (by June 1941, the USAAF) promoted the aircraft as a strategic weapon; it was a relatively fast, high-flying, long-range bomber with heavy defensive armament at the expense of bombload. It developed a reputation for toughness based upon stories and photos of badly damaged B-17s safely returning to base. The B-17 dropped more bombs than any other U.S. aircraft in World War II. Of approximately 1.5 million tons of bombs dropped on Nazi Germany and its occupied territories by U.S. aircraft, over 640,000 tons were dropped from B-17s. In addition to its role as a bomber, the B-17 was also employed as a transport, antisubmarine aircraft, drone controller, and search-and-rescue aircraft.

As of October 2019, 9 aircraft remain airworthy, though none of them were ever flown in combat. Dozens more are in storage or on static display. The oldest of these is a D-series flown in combat in the Pacific and the Caribbean.

Childress Army Airfield

Childress Army Airfield is a former World War II military airfield, located 4.8 miles west of Childress, Texas. It operated as a Bombardier training school for the United States Army Air Forces from 1942 until 1945.

David M. Gonzales

Private First Class David M. Gonzales (June 9, 1923 – April 25, 1945) was a United States Army soldier who posthumously received the Medal of Honor — the United States' highest military decoration — for his actions during World War II. On April 25, 1945, at age 21, PFC Gonzales was killed in action in the Philippines while, in the face of enemy machine gun fire, digging out fellow soldiers who had been buried in a bomb explosion.

Fighter-bomber

A fighter-bomber is a fighter aircraft that has been modified, or used primarily, as a light bomber or attack aircraft. It differs from bomber and attack aircraft primarily in its origins, as a fighter that has been adapted into other roles, whereas bombers and attack aircraft are developed specifically for bombing and attack roles.

Although still used, the term fighter-bomber has less significance since the introduction of rockets and guided missiles into aerial warfare. Modern aircraft with similar duties are now typically called multirole combat aircraft or strike fighters.

George Kenney

George Churchill Kenney (6 August 1889 – 9 August 1977) was a United States Army Air Forces general during World War II. He is best known as the commander of the Allied Air Forces in the Southwest Pacific Area (SWPA), a position he held between August 1942 and 1945.

Kenney enlisted as a flying cadet in the Aviation Section, U.S. Signal Corps in 1917, and served on the Western Front with the 91st Aero Squadron. He was awarded a Silver Star and the Distinguished Service Cross for actions in which he fought off German fighters and shot two down. After hostilities ended he participated in the Occupation of the Rhineland. Returning to the United States, he flew reconnaissance missions along the border between the US and Mexico during the Mexican Revolution. Commissioned into the Regular Army in 1920, he attended the Air Corps Tactical School, and later became an instructor there. He was responsible for the acceptance of Martin NBS-1 bombers built by Curtis, and test flew them. He also developed techniques for mounting .30 caliber machine guns on the wings of an Airco DH.4 aircraft.

In early 1940, Kenney became Assistant Military Attaché for Air in France. As a result of his observations of German and Allied air operations during the early stages of World War II, he recommended significant changes to Air Corps equipment and tactics. In July 1942, he assumed command of the Allied Air Forces and Fifth Air Force in General Douglas MacArthur's Southwest Pacific Area. Under Kenney's command, the Allied Air Forces developed innovative command structures, weapons, and tactics that reflected Kenney's orientation towards attack aviation. The new weapons and tactics won perhaps his greatest victory, the Battle of the Bismarck Sea, in March 1943. In June 1944 he was appointed commander of the Far East Air Forces (FEAF), which came to include the Fifth, Thirteenth, and Seventh Air Forces.

In April 1946, Kenney became the first commander of the newly formed Strategic Air Command (SAC), but his performance in the role was criticized, and he was shifted to become commander of the Air University, a position he held from October 1948 until his retirement from the Air Force in September 1951.

Holman Projector

The Holman Projector was an anti-aircraft weapon used by the Royal Navy during World War II, primarily between early 1940 and late 1941. The weapon was proposed and designed by Holmans, a machine tool manufacturer based at Camborne, Cornwall. A number of models were produced during the war years, but all worked on the principle of a pneumatic mortar, using compressed air or high pressure steam to fire an explosive projectile at enemy aircraft.Intended primarily as a stop-gap defensive weapon for British merchant ships, which had been suffering heavy losses from Luftwaffe aircraft flying anti-shipping missions, the low altitude at which such strikes often took place (such as during torpedo attacks by Heinkel He 111's or skip-bombing attacks by Focke-Wulf Fw 200 Condor) meant that a weapon of such limited range and velocity could throw up an effective screen of fire over a vessel, even if only to create a distracting or deterrent effect, obliging the enemy to bomb from greater heights which reduced bombing accuracy.

While ineffective against normal bombing attacks from higher altitudes, the weapon was far cheaper, easier to build and install in great numbers than conventional anti-aircraft artillery.

Holmans specialised in producing gas compressors and pneumatic equipment and its owner, Treve Holman, conceived a way that his firm could aid in the war effort beyond the production of tools. Recalling the World War I-era Stokes Mortar and its successor, the Ordnance ML 3 inch Mortar, Holman believed that it would be possible to produce a version powered by compressed air.

Preliminary tests showed that the idea was feasible, with an early prototype throwing an eighteen-pound steel weight nearly 100 yards (91 m).

Holtville Airport

Holtville Airport (FAA LID: L04) is a county-owned, public-use airport located five nautical miles (9 km) northeast of the central business district of Holtville, a city in Imperial County, California, United States. Holtville was a U.S. Navy airfield during World War II.

Howard Knox Ramey

Howard Knox Ramey (28 June 1896 – 26 March 1943) was a United States Army Air Forces general during World War II. Ramey learned to fly in 1918 during World War I and served as an instructor at the Air Corps Advanced Flying School and as a staff officer with the 1st Bombardment Wing between the wars. He was commander of the IV Bomber Command from 12 August 1942 to 8 November 1942, and was promoted to brigadier general on 17 September 1942. In November 1942, he became deputy commander of the Seventh Air Force in Hawaii. In January 1943 he became the commander of the V Bomber Command in Australia and Papua, which he led during the Battle of the Bismarck Sea. In March 1943 he disappeared on a reconnaissance flight over the Torres Strait. Neither his aircraft nor his body has ever been found.

Issaqueena Bombing Range

The Issaqueena Bombing Range was a World War II target range used for training flight crews from Greenville Army Air Base, later renamed Donaldson Air Force Base. The Army Air Field was established in 1942 for the preparation of aircrew using North American B-25 Mitchell twin-engine bombers, and a suitable target area was established using Lake Issaqueena, northwest of Calhoun, South Carolina and Clemson College, completely within the Clemson Experimental Forest. Bombing Range Road is still located off of State Highway S-39-291, southwest of Six Mile, South Carolina and west of Lake Issaqueena.

Muroc Maru

Muroc Maru, officially AAF Temporary Building (Target) T-799, was a replica of a Japanese Takao-class cruiser constructed on the floor of Rogers Dry Lake in southern California during World War II. Used to train bomber pilots and bombardiers in techniques for attacking warships, Muroc Maru remained in place until 1950, when it was demolished.

Norden bombsight

The Norden Mk. XV, known as the Norden M series in U.S. Army service, was a bombsight used by the United States Army Air Forces (USAAF) and the United States Navy during World War II, and the United States Air Force in the Korean and the Vietnam Wars. It was an early tachometric design, a system that allowed it to directly measure the aircraft's ground speed and direction, which older bombsights could only estimate with lengthy in-flight procedures. The Norden further improved on older designs by using an analog computer that constantly calculated the bomb's impact point based on current flight conditions, and an autopilot that let it react quickly and accurately to changes in the wind or other effects.

Together, these features seemed to promise unprecedented accuracy in day bombing from high altitudes; in peacetime testing the Norden demonstrated a circular error probable (CEP) of 75 feet (23 m), an astonishing performance for the era. This accuracy would allow direct attacks on ships, factories, and other point targets. Both the Navy and the USAAF saw this as a means to achieve war aims through high-altitude bombing; for instance, destroying an invasion fleet by air long before it could reach U.S. shores. To achieve these aims, the Norden was granted the utmost secrecy well into the war, and was part of a then-unprecedented production effort on the same scale as the Manhattan Project. Carl L. Norden, Inc. ranked 46th among United States corporations in the value of World War II military production contracts.In practice it was not possible to achieve the expected accuracy in combat conditions, with the average CEP in 1943 of 370 metres (1,200 ft) being similar to Allied and German results. Both the Navy and Air Forces had to give up on the idea of pinpoint attacks during the war. The Navy turned to dive bombing and skip bombing to attack ships, while the Air Forces developed the lead bomber concept to improve accuracy, while adopting area bombing techniques by ever larger groups of aircraft. Nevertheless, the Norden's reputation as a pin-point device lived on, due in no small part to Norden's own advertising of the device after secrecy was reduced late in the war.

This secrecy had already been compromised by espionage before the United States entered the war. As early as January 1941, the Germans introduced a lightened version of the Norden called the Carl Zeiss Lotfernrohr 7 as the primary bombsight for most Luftwaffe level bombers and the first of its bombsights to have gyroscopic stabilization.

The Norden saw some use in the post-World War II era, especially during the Korean War. Post-war use was greatly reduced due to the introduction of radar-based systems, but the need for accurate daytime attacks kept it in service for some time. The last combat use of the Norden was in the U.S. Navy's VO-67 squadron, which used them to drop sensors onto the Ho Chi Minh Trail as late as 1967. The Norden remains one of the best-known bombsights of all time.

North American B-25 Mitchell

The North American B-25 Mitchell is a medium bomber that was introduced in 1941 and named in honor of Major General William "Billy" Mitchell, a pioneer of U.S. military aviation. Used by many Allied air forces, the B-25 served in every theater of World War II, and after the war ended, many remained in service, operating across four decades. Produced in numerous variants, nearly 10,000 B-25s were built. These included a few limited models such as the F-10 reconnaissance aircraft, the AT-24 crew trainers, and the United States Marine Corps' PBJ-1 patrol bomber.

Stone skipping

Stone skipping (or stone skimming) is the art of throwing a flat stone across water in such a way (usually Sidearm) that it bounces off the surface, preferably many times. The objective of the game is to see how many times a stone can bounce before sinking.

Toss bombing

Toss bombing (sometimes known as loft bombing, and by the U.S. Air Force as the Low Altitude Bombing System, LABS) is a method of bombing where the attacking aircraft pulls upward when releasing its bomb load, giving the bomb additional time of flight by starting its ballistic path with an upward vector.

The purpose of toss bombing is to compensate for the gravity drop of the bomb in flight, and allow an aircraft to bomb a target without flying directly over it. This is in order to avoid overflying a heavily defended target, or in order to distance the attacking aircraft from the blast effects of a nuclear (or conventional) bomb.

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