The Lockheed XB-30 (company model L-249) was the design submitted by Lockheed after the request by the United States Army Air Forces for a very heavy bomber, the same request that led to the Boeing B-29 Superfortress, the Douglas XB-31 and Consolidated B-32 Dominator.
|Scale model of the Lockheed XB-30 bomber concept.|
|Primary user||United States Army Air Forces|
|Developed from||L-049 Constellation|
Around 1938, General Henry H. "Hap" Arnold, the head of the United States Army Air Corps, was growing alarmed at the possibility of war in Europe and in the Pacific. Hoping to be prepared for the long-term requirements of the Air Corps, Arnold created a special committee chaired by Brigadier General Walter G. Kilner; one of its members was Charles Lindbergh. After a tour of Luftwaffe bases, Lindbergh became convinced that Nazi Germany was far ahead of other European nations.
In a 1939 report, the committee made a number of recommendations, including development of new long-range heavy bombers. When war broke out in Europe, Arnold requested design studies from several companies on a Very Long-Range bomber capable of traveling 5,000 miles (8,000 km). Approval was granted on 2 December 1939.
Based on the design of the Lockheed L-049 (subsequently adopted by the United States Army Air Forces as the C-69), the L-249 never progressed past the design stage, mainly because Boeing had a huge head start with its Boeing B-29 Superfortress, using the same Wright R-3350 Duplex-Cyclone radials as the XB-30 was intended to use. Only a scale model was built. Retaining the wings and tail surfaces of the Model 49, the Model 249-58-01 was to have had a new fuselage with up to six gun turrets (one in the nose, two above and two below the fuselage, and one in the tail) housing 10 .50-caliber guns—twinned up in each turret for the nose, dorsal, and ventral emplacements; and one 20-mm cannon for the tail defensive position. Ventral bomb bays were to accommodate eight 2,000-lb. (907 kg.) bombs.
Aircraft of comparable role, configuration and era
B30 may refer to:
Sicilian Defence, Encyclopaedia of Chess Openings code
Bundesstraße 30, a German road
Lockheed XB-30, an aircraft
Route B30 (WMATA), a bus route operating between BWI Airport and Greenbelt Metrorail Station
B30, a spent fuel storage pond at the Sellafield nuclear reprocessing siteBoeing B-29 Superfortress
The Boeing B-29 Superfortress is a four-engine propeller-driven heavy bomber designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to its predecessor, the B-17 Flying Fortress, the Superfortress was designed for high-altitude strategic bombing but also excelled in low-altitude night incendiary bombing, and in dropping naval mines to blockade Japan. B-29s also dropped the atomic bombs on Hiroshima and Nagasaki which contributed to the end of World War II.
One of the largest aircraft of World War II, the B-29 had state-of-the-art technology, including a pressurized cabin; dual-wheeled, tricycle landing gear; and an analog computer-controlled fire-control system that allowed one gunner and a fire-control officer to direct four remote machine gun turrets. The $3 billion cost of design and production (equivalent to $42 billion today)—far exceeding the $1.9 billion cost of the Manhattan Project—made the B-29 program the most expensive of the war.The B-29's advanced design allowed it to remain in service in various roles throughout the 1950s. The type was retired in the early 1960s, after 3,970 had been built.
A few were used as flying television transmitters by the Stratovision company. The Royal Air Force flew the B-29 as the Washington until 1954.
The B-29 was the progenitor of a series of Boeing-built bombers, transports, tankers, reconnaissance aircraft and trainers. The re-engined B-50 Superfortress became the first aircraft to fly around the world non-stop, during a 94-hour flight in 1949. The Boeing C-97 Stratofreighter airlifter, first flown in 1944, was followed in 1947 by its commercial airliner variant, the Boeing Model 377 Stratocruiser. This bomber-to-airliner derivation was similar to the B-17/Model 307 evolution. In 1948, Boeing introduced the KB-29 tanker, followed in 1950 by the Model 377-derivative KC-97. A line of outsized-cargo variants of the Stratocruiser is the Guppy / Mini Guppy / Super Guppy, which remain in service with NASA and other operators.
The Soviet Union produced an unlicensed reverse-engineered copy, the Tupolev Tu-4.
More than twenty B-29s remain as static displays but only two, Fifi and Doc, still fly.Consolidated B-32 Dominator
The Consolidated B-32 Dominator (Consolidated Model 34) was an American heavy strategic bomber built for United States Army Air Forces during World War II, which had the distinction of being the last Allied aircraft to be engaged in combat during World War II. It was developed by Consolidated Aircraft in parallel with the Boeing B-29 Superfortress as a fallback design should the B-29 prove unsuccessful. The B-32 only reached units in the Pacific during mid-1945, and subsequently only saw limited combat operations against Japanese targets before the end of the war. Most of the extant orders of the B-32 were canceled shortly thereafter and only 118 B-32 airframes of all types were built.Douglas XB-31
The Douglas XB-31 (Douglas Model 332) was the design submitted by Douglas after the request by the United States Army Air Forces for a very heavy bomber aircraft, the same request that led to the Boeing B-29 Superfortress, Lockheed XB-30, and Consolidated B-32 Dominator.List of United States bomber aircraft
This is a list of United States bomber aircraftList of bomber aircraft
The following is a list of bomber airplanes and does not include bomber airships, organized by era and manufacturer. A bomber is a military aircraft designed to attack ground or sea targets.List of cancelled military projects
This is a list of cancelled military projects.Lockheed Constellation
The Lockheed Constellation ("Connie") is a propeller-driven, four-engine airliner built by Lockheed Corporation between 1943 and 1958 at Burbank, California. Lockheed built 856 in numerous models—all with the same triple-tail design and dolphin-shaped fuselage. Most were powered by four 18-cylinder Wright R-3350 Duplex-Cyclones. The Constellation was used as a civil airliner and as a military and civilian air transport, seeing service in the Berlin and the Biafran airlifts. The Constellation series was the first pressurized-cabin civil airliner series to go into widespread use. Its pressurized cabin enabled large numbers of commercial passengers to fly well above most bad weather for the first time, thus significantly improving the general safety and ease of air travel. Three of them served as the presidential aircraft for Dwight D. Eisenhower.Lockheed L-049 Constellation
The Lockheed L-049 Constellation was the first model of the Lockheed Constellation aircraft line. It entered service as the C-69 military transport aircraft during World War II for the United States Army Air Forces and was the first civilian version after the war. When production ended in 1946 it was replaced by the improved L-649 and L-749 Constellation.Wright R-3350 Duplex-Cyclone
The Wright R-3350 Duplex-Cyclone is a twin-row, supercharged, air-cooled, radial aircraft engine with 18 cylinders displacing nearly 55 L. Power ranged from 2,200 to over 3,700 hp (1,640 to 2,760 kW), depending on the model. Developed before World War II, the R-3350's design required a long time to mature before finally being used to power the Boeing B-29 Superfortress. After the war, the engine had matured sufficiently to become a major civilian airliner design, notably in its turbo-compound forms, and was used in the Lockheed L-1049 Super Constellation airliners into the 1990s. The engine is now commonly used on Hawker Sea Fury and Grumman F8F Bearcat Unlimited Class Racers at the Reno Air Races. Its main rival was the Pratt & Whitney R-4360 Wasp Major.