Heavy bomber
Heavy bombers are
Because of advances in
During World War II, mass production techniques made available large, long-range heavy bombers in such quantities as to allow strategic bombing campaigns to be developed and employed. This culminated in August 1945, when B-29s of the United States Army Air Forces dropped atomic bombs over Hiroshima and Nagasaki in Japan.
The arrival of
Heavy bombers are now operated only by the air forces of the United States, Russia and China. They serve in both strategic and tactical bombing roles.
History
World War I
The first heavy bomber was designed as an airliner. Igor Sikorsky, an engineer educated in St Petersburg, but born in Kiev of Polish-Russian ancestry designed the Sikorsky Ilya Muromets to fly between his birthplace and his new home. It did so briefly until August 1914, when the Russo-Balt wagon factory converted to a bomber version, with British Sunbeam Crusader V8 engines in place of the German ones in the passenger plane. By December 1914 a squadron of 10 was bombing German positions on the Eastern Front and by summer 1916 there were twenty. It was well-armed with nine machine guns, including a tail gun and initially was immune to German and Austro-Hungarian air attack.[1] The Sikorsky bomber had a wingspan just a few feet shorter than, with a bomb load only 3% of, a World War II Avro Lancaster.[2]
The Handley Page Type O/100 owed a lot to Sikorsky's ideas; of similar size, it used just two Rolls-Royce Eagle engines and could carry up to 2,000 lb (910 kg) of bombs. The O/100 was designed at the beginning of the war for the Royal Navy specifically to sink the German High Seas Fleet in Kiel: the Navy called for “a bloody paralyser of an aircraft”[3] Entering service in late 1916 and based near Dunkirk in France, it was used for daylight raids on naval targets, damaging a German destroyer.[4] But after one was lost, the O/100 switched to night attacks.
The uprated
The
German aircraft companies also built a number of giant bombers, collectively known as the Riesenflugzeug. Most were produced in very small numbers from 1917 onwards and several never entered service. The most numerous were the Zeppelin-Staaken R.VI of which 13 saw service, bombing Russia and London: four were shot down and six lost on landing. The R.VIs were larger than the standard Luftwaffe bombers of World War II.[7]
The Vickers Vimy, a long-range heavy bomber powered by two Rolls-Royce Eagle engines, was delivered to the newly formed Royal Air Force too late to see action (only one was in France at time of the Armistice with Germany). The Vimy's intended use was to bomb industrial and railway targets in western Germany, which it could reach with its range of 900 miles (1,400 km) and a bomb load of just over a ton. The Vickers Vimy is best known as the aircraft that made the first Atlantic crossing from St John's Newfoundland to Clifden in Ireland piloted by the Englishman John Alcock and navigated by Scot Arthur Whitten Brown on June 14, 1919.[8]
Strategic bomber theory
Between the wars, aviation opinion fixed on two tenets. The first was that “the bomber will always get through.” The speed advantage of biplane fighters over bombers was insignificant, and it was believed that they would never catch them. Furthermore, there was no effective method of detecting incoming bombers at sufficiently long range to scramble fighters on an interception course. In practice, a combination of new radar technology and advances in monoplane fighter design eroded this disadvantage. Throughout the war, bombers continually managed to strike their targets, but suffered unacceptable losses in the absence of careful planning and escort fighters. Only the later de Havilland Mosquito light bomber was fast enough to evade fighters. Heavy bombers needed defensive armament for protection, which reduced their effective bomb payload.[9]
The second tenet was that strategic bombing of industrial capacity, power generation, oil refineries, and coal mines could win a war. This was certainly vindicated by the
As the
World War II
When Britain and France declared war on Germany in September 1939, the RAF had no heavy bomber yet in service; heavy bomber designs had started in 1936 and ordered in 1938.
The Handley Page Halifax and Avro Lancaster both originated as twin-engine "medium" bombers, but were rapidly redesigned for four Rolls-Royce Merlin engines and rushed into service once the technical problems of the larger Rolls-Royce Vulture emerged in the Avro Manchester. The Halifax joined squadrons in November 1940 and flew its first raid against Le Havre on the night of 11–12 March 1941. British heavy bomber designs often had three gun turrets with a total of 8 machine guns.
In January 1941, the Short Stirling reached operational status and first combat missions were flown in February. It was based on the successful Short Sunderland flying boat and shared its Bristol Hercules radial engines, wing, and cockpit with a new fuselage. It carried up to 14,000 lb (6,400 kg) of bombs—almost twice the load of a Boeing B-17 Flying Fortress—but over just a 300-mile (480 km) radius. Due to its thick, short wing it was able to out-turn the main German night fighters, the Messerschmitt Bf 110 and the Junkers Ju 88. Heavy bombers still needed defensive armament for protection, even at night. The Stirling's low operational ceiling of just 12,000 ft (3,700 m)—also caused by the thick wing—meant that it was usually picked on by night fighters; within five months, 67 of the 84 aircraft in service had been lost. The bomb bay layout limited the size and types of bombs carried and it was relegated to secondary duties such as tug and paratrooper transport.
Due to the absence of British heavy bombers, 20 United States Army Air Corps Boeing B-17 Flying Fortresses were lent to the RAF, which during July 1941 commenced daylight attacks on warships and docks at Wilhelmshaven and Brest. These raids were complete failures. After eight aircraft were lost due to combat or breakdown and with many engine failures, the RAF stopped daylight bombing by September.[10] It was clear that the B-17C model was not combat ready and that its five machine guns provided inadequate protection.
Combat feedback enabled Boeing engineers to improve the aircraft; when the first model B-17E began operating from English airfields in July 1942, it had many more defensive gun positions including a vitally important tail gunner. Eventually, U.S. heavy bomber designs, optimized for formation flying, had 10 or more machine guns and/or
Even this extra firepower, which increased empty weight by 20% and required more powerful versions of the
The USAAF chose to attack aircraft factories and component plants. On August 17, 1943, 230 Fortresses attacked a ball-bearing plant in Schweinfurt and again two months later, with 291 bombers, in the
With the arrival of North American P-51 Mustangs and the fitting of drop tanks to increase the range of the Republic P-47 Thunderbolt for the Big Week offensive, between February 20–25, 1944, bombers were escorted all the way to the target and back. Losses were reduced to 247 out of 3,500 sorties, still devastating but accepted at the time.
The Consolidated B-24 Liberator and later version of the Fortress carried even more extensive defensive armament fitted into Sperry ball turrets. This was a superb defensive weapon that rotated a full 360 degrees horizontally with a 90-degree elevation. Its twin M2 Browning machine guns had an effective range of 1,000 yards (910 m). The Liberator was the result of a proposal to assemble Fortresses in Consolidated plants, with the company returning with its own design of a longer-range, faster and higher-flying aircraft that could carry an extra ton of bombs. Early orders were for France (delivered to the RAF after the fall of France) and Britain, already at war, with just a batch of 36 for the USAAF.[14]
Neither the USAAF nor the RAF judged the initial design suitable for bombing and it was first used on a variety of VIP transport and maritime patrol missions. Its long range, however, persuaded the USAAF to send 177 Liberators from Benghazi in Libya to bomb the Romanian oilfields on August 1, 1943, in Operation Tidal Wave. Due to navigational errors and alerted German flak batteries and fighters, only half returned to base although a few landed safely at RAF bases in Cyprus and some in Turkey, where they were interned. Only 33 were undamaged. Damage to the refineries was soon repaired and oil production actually increased[15]
By October 1942, a new Ford Motor Company plant at Willow Run Michigan was assembling Liberators. Production reached a rate of over one an hour in 1944 helping the B-24 to become the most produced US aircraft of all time. It became the standard heavy bomber in the Pacific and the only one used by the RAAF. The SAAF used Liberators to drop weapons and ammunition during the Warsaw Uprising in 1944.[16]
The Avro Manchester was a twin-engine bomber powered by the ambitious 24-cylinder Rolls-Royce Vulture, but was rapidly redesigned for four Rolls-Royce Merlin engines due to technical problems with the Vulture which caused the aircraft to be unreliable, under-powered and hastened its withdrawal from service. Reaching squadrons early in 1942, the redesigned bomber with four Merlin engines and longer wings was renamed Avro Lancaster; it could deliver a 14,000 lb (6,400 kg) load of bombs or up to 22,000 lb (10,000 kg) with special modifications. The Lancaster's bomb bay was undivided, so that bombs of extraordinary size and weight such as the 10-ton Grand Slam could be carried.[17]
In March and April 1945, as the war in Europe was ending, Lancasters dropped Grand Slams and Tallboys on U-boat pens and railway viaducts across north Germany. At Bielefeld more than 100 yards (91 m) of railway viaduct was destroyed by Grand Slams creating an earthquake effect, which shook the foundations.[19]
The Boeing B-29 Superfortress was a development of the Fortress, but a larger design with four Wright R-3350 Duplex-Cyclone engines of much greater power, enabling it to fly higher, faster, further and with a bigger bomb load. The mammoth new Wright radial engines were susceptible to overheating if anything malfunctioned, and technical problems with the powerplant seriously delayed the B-29's operational service debut. The aircraft had four remotely operated twin-gun turrets on its fuselage, controlled through an analog computer sighting system; the operator could use any of a trio of Perspex ball stations. Only the tail gunner manually controlled his gun turret station in the rear of the airplane.[20]
B-29s were initially deployed to bases in India and China, from which they could reach Japan; but the logistics (including transport of fuel for the B-29 fleet over the
After World War II
After World War II, the name strategic bomber came into use, for aircraft that could carry aircraft ordnances over long distances behind enemy lines. They were supplemented by smaller fighter-bombers with less range and lighter bomb load, for tactical strikes. Later these were called strike fighters, attack aircraft and multirole combat aircraft.
When North Korea attacked South Korea in 1950 the USAF responded with daylight bomber raids on supply lines through North Korea. B-29 Superfortresses flew from Japan on behalf of the United Nations, but the supply line for North Korea's army from the Soviet Union was physically and politically out of reach: North Korea for the most part lacked worthwhile strategic targets of its own. The Soviet-backed Northern forces easily routed the South Korean army.[22] The distance to North Korea was too great for fighter escorts based in Japan, so the B-29s flew alone. In November, Mikoyan-Gurevich MiG-15s flown by Soviet pilots started to intercept the US bombers over North Korea. The MiG-15 was specifically designed to destroy US heavy bombers; it could out-perform any fighter deployed by United Nations air forces until the capable F-86 Sabre was produced in greater numbers and brought to Korea. After 28 B-29s were lost, the bombers were restricted to night interdiction and concentrated on destroying supply routes, including the bridges over the Yalu river into China.[23]
By the 1960s, manned heavy bombers could not match the intercontinental ballistic missile in the strategic nuclear role. More accurate precision-guided munitions ("smart bombs"), nuclear-armed missiles or bombs were able to be carried by smaller aircraft such as fighter-bombers and multirole fighters. Despite these technological innovations and new capabilities of other contemporary military aircraft, large strategic bombers such as the B-1, B-52 and B-2 have been retained for the role of carpet bombing in several conflicts. The most prolific example (in terms of total bomb tonnage) is the U.S. Air Force B-52 Stratofortress during the 1960s–early 1970s Vietnam War era, in Operation Menu, Operation Freedom Deal, and Operation Linebacker II. In 1987 the Soviet Tu-160—the heaviest supersonic bomber/aircraft currently in active service—entered service; it can carry twelve long-range cruise missiles.
The 2010
- range greater than 8,000 kilometres (5,000 mi)
- equipped for long-range nuclear "air-launched cruise missiles" (ALCMs), defined as an air-to-surface cruise missile of a type flight-tested from an aircraft or deployed on a bomber after 1986.
List of heavy bombers
Some notable heavy bombers are listed below
World War I
- AEG G.I, II, III, IV, V, R.I
- Airco DH.10 Amiens
- Albatros G.I, II, III
- Blériot 73
- Caproni Ca.1, Ca.3 Ca.4, Ca.5
- Caudron R.11
- Farman F.50
- Friedrichshafen G.II, G.III, G.IV
- Gotha G.I, G.II, G.III, G.IV G.V
- Handley Page Type O/100 & O/400
- Handley Page V/1500
- Letord Let.3 6 & 7
- Martin MB-1
- Rumpler G.I, G.II & G.III
- Short Bomber
- Sikorsky Ilya Muromets
- Vickers Vimy
- Zeppelin-Staaken R.VI
- Zeppelin-Staaken R.XV
- Zeppelin-Staaken R.XVI
Interwar period (interbellum)
- Armstrong Whitworth Whitley
- Avro 549 Aldershot
- Avro Manchester
- Blériot 127
- Boeing B-17 Flying Fortress
- Bréguet 410
- Bristol Bombay
- Curtiss B-2 Condor
- Dornier Do 11
- Douglas Y1B-7
- Douglas B-18 Bolo
- Farman BN.4
- Farman F.60 Goliath
- Farman F.120
- Farman F.220
- Fokker XB-8
- Friedrichshafen G.V
- Handley Page H.P.54 Harrow
- Handley Page Heyford
- Handley Page Hinaidi
- Handley Page Hyderabad
- Lioré et Olivier LeO 20
- Martin NBS-1/MB-2
- Mitsubishi Ki-20
- Mitsubishi Ki-21
- Petlyakov Pe-8
- Tupolev TB-1
- Tupolev TB-3
- Vickers Virginia
World War II
- Avro Lancaster
- Avro Lincoln
- Boeing B-17 Flying Fortress
- Consolidated B-24 Liberator
- Boeing B-29 Superfortress
- Consolidated B-32 Dominator
- Handley Page Halifax
- Heinkel He 177
- Piaggio P.108
- Savoia-Marchetti SM.82
- Short Stirling
- Vickers Warwick
Post-WW2
- Avro Vulcan
- Boeing B-47 Stratojet
- Boeing B-50 Superfortress
- Boeing B-52 Stratofortress
- Convair B-36 Peacemaker
- Convair B-58 Hustler
- Handley Page Victor
- Myasishchev M-4
- Northrop Grumman B-2 Spirit
- Northrop Grumman B-21 Raider
- Rockwell B-1 Lancer
- Short Sperrin
- Sukhoi T-4
- Tupolev Tu-4
- Tupolev Tu-16
- Tupolev Tu-22M
- Tupolev Tu-95
- Tupolev Tu-160
- Vickers Valiant
- Xian H-6
Notes
- ISBN 1840136413
- ISBN 0760705925
- ISBN 1557500762
- ISBN 0946627681
- ^ Bruce, J. M. Handley Page 0/100 and 0/400: Historic Military Aircraft No.4. Flight ;27 February 1953, Vol. LXIII. issue No. 2301
- ISBN 0370305388
- ^ G.W. Haddow & Peter M. Grosz The German Giants, The Story of the R-planes 1914–1919, Putnam & Company Limited, London 1962
- ISBN 0851778151
- ^ ISBN 1428912576.
- ISBN 1855018071
- ISBN 0913194042.
- ISBN 0913194042
- ISBN 091279903X
- ISBN 0668016957.
- ISBN 1574885103
- ISBN 978-0330488631
- ISBN 1854094564
- ISBN 978-0552163415
- ISBN 0752429876
- ISBN 188058879X
- ISBN 188058879X
- ISBN 1579583644
- ISBN 1857801059
References
This article includes a list of general references, but it lacks sufficient corresponding inline citations. (October 2009) |
- Ambrose, Stephen E. The Wild Blue: The Men and Boys Who Flew the B-24s over Germany. New York: Simon & Schuster, 2001. p. 299 [ISBN missing]
- Johnsen, Frederick A. "Ball Turret: Shattering the Myths." Air Power History 1996 43(2): pp. 14–21. ISSN 1044-016X
- Johnson, Robert E. "Why the Boeing B-29 Bomber, and Why the Wright R-3350 Engine?" American Aviation Historical Society Journal 1988 33(3): pp. 174–189. ISSN 0002-7553
- VanderMeulen, Jacob. Building the B-29. Smithsonian Inst. Press, 1995. p. 104 [ISBN missing]