|Manufacturer||North American Aviation|
|Status||3 on display in museums|
|Primary user||United States Air Force|
|Unit cost||US$1.1 million|
The North American B-45 Tornado was the United States Air Force's first operational jet bomber, and the first jet aircraft to be refueled in the air. The B-45 was an important part of the United States's nuclear deterrent for several years in the early 1950s, but was rapidly succeeded by the Boeing B-47 Stratojet.
The B-45 began development in 1944, when the War Department, alarmed by German jet bombers like Arado Ar 234 and Junkers Ju 287, called for a new family of jet bombers grossing between 80,000 and 200,000 pounds. The North American proposal (NA-130) won, and on September 8, 1944, the company began production of three prototypes based on the NA-130.
The end of the Second World War resulted in the cancellation of many projects and delayed many others. In 1946, rising tensions with the Soviet Union caused the Air Force to assign higher priorities to jet bomber development and production. By mid-1946, the XB-45 and XB-46 neared completion, but the XB-47 and XB-48 were still two years away. The USAAF chose to evaluate the first two designs to determine which would be superior operationally. The B-45 proved a superior design, and on January 2, 1947, a contract for immediate production of B-45As was signed.
Variants and design stages
The first flight of the XB-45 was on March 17, 1947 from Muroc Army Air Field. A total of 131 test flights were flown by the three prototype aircraft, one being destroyed early on, killing two pilots.
The USAF accepted one of the two survivors on July 30, 1948, the other on August 31. One was damaged beyond repair in an accident. The last XB-45 was delivered to Wright-Patterson Air Force Base air force base in 1949. It proved excessively difficult to maintain and was relegated as a ground trainer.
The first production B-45 flew in February 1948. The Air Force took delivery of 22 in April 1948. They were powered by the less-powerful J35 turbojets, and not considered combat-ready. They were assigned to training duties and various test programs. The next batch were powered by the superior J47 turbojets. The first B-45As entered service in November 1948 with the 47th Bombardment Group. The initial order of 96 was completed in March 1950.
It had been planned to equip five light bomb groups and three light reconnaissance groups with B-45As. Severe budget cuts in the FY 1950 forced the Aircraft and Weapons Board to cancel 51 of the 190 aircraft on order.
The first B-45As were not equipped with bomb fire control systems or bombsights. They suffered from gyrocompass failures at high speeds, unreliable airbrakes, unhooked bomb shackles, engine fires, and inaccurate cockpit gauges. The AN/APQ-24 bombing and navigation radar on some B-45s was maintenance heavy and malfunctions in the pressurization pump limited the altitude at which it could operate.
It was proposed to transfer the 47's B-45s to the Far East, though no suitable transport could be found. At the outbreak of the Korean War it was decided to convert the B-45A to a tactical nuclear bomber. The B-45 could not carry early nuclear weapons due to their large size. Even with the development of smaller bombs, the aircraft required extensive modification.
55 nuclear-capable B-45s arrived in the United Kingdom in 1952. These were modified with a 1,200-gallon fuel tank in the aft bomb bay. Despite technical problems, these were SAC's first-line deterrent in Europe.
The B-45B was a proposed variant of the B-45A with improved radar and fire-control systems. None were built.
The B-45C was the first jet aircraft capable of aerial refueling. It carried two 1200-gallon wingtip fuel tanks, had a strengthened canopy, and an in-flight refueling receptacle. The first B-45C was flown on May 3, 1949. Only ten were built, and the remaining 33 under construction were converted to RB-45Cs.
Final production variant of the B-45. The bombardier's canopy was faired over and replaced with an oblique camera system. The RB-45C carried two 214-gallon external fuel tanks, or two JATO assisted takeoff rockets. A total of up to 12 cameras could be carried in four positions or a single camera configuration with a 100 inch focal length lens. The RB-45C first flew in April 1950, and were delivered from June 1950 to October 1951.
RB-45Cs flew with the Strategic Air Command 324th SRS, 91st SRW, along side the 91st Strategic Reconnaissance Squadron during the Korean war, as B-29s could no longer fly these missions safely. RB-45Cs flew many missions until early 1952, when they were converted to night operations. They were withdrawn shortly afterwards.
The RB-45C also flew several long-range reconnaissance missions over the Soviet Union during the mid 1950s. On July 29, 1952, an RB-45C made the first non-stop Trans-Pacific flight, having been refueled twice by KB-29s along the way. By 1959 the RB-45C had been replaced by the RB-47E.
Three B-45s are currently on display in the United States. B-45A (s/n 47-0008) is currently on display at the Castle Air Museum in Atwater, California. B-45C (s/n 48-010) is on display in the Cold War Hangar of the National Museum of the United States Air Force near Dayton, Ohio, and a RB-45C (s/n 48-017) is on display at the Strategic Air and Space Museum in Ashland, Nebraska.
- Crew: 4
- Length: 75 ft 4 in (22.9 m)
- Wingspan: 89 ft 0 in (27.1 m)
- Height: 25 ft 2 in (7.7 m)
- Wing area: 1,125 ft² (105 m²)
- Empty weight: 45,694 lb (20,726 kg)
- Loaded weight: 81,418 lb (36,930 kg)
- Max takeoff weight: 110,000 lb (50,000 kg)
- Powerplant: 4× General Electric J47-GE-13 turbojets, 5,200 lbf (25 kN) each
- Maximum speed: 500 knots (570 mph, 920 km/h)
- Range: 870 nm (1,000 mi, 1,600 km)
- Service ceiling: 46,400 ft (14,100 m)
- Rate of climb: 5,950 ft/min (1,810 m/min)
- Wing loading: 72.37 lb/ft² (353.4 kg/m²)
- Thrust/weight: 0.26
- Guns: 2× .50 in (12.7 mm) M3 machine guns
- Bombs: 22,000 lb (10,000 kg)
- Knaack, Marcelle Size (1988). Post-World War II bombers, 1945-1973. Office of Air Force History. ISBN 0-16-002260-6.
- Convair XB-46
- B-47 Stratojet
- Martin XB-48
- Arado Ar 234
- Junkers Ju 287
- Short Sperrin
- English Electric Canberra
Lists relating to aviation
|General||Timeline of aviation · Aircraft · Aircraft manufacturers · Aircraft engines · Aircraft engine manufacturers · Airports · Airlines|
|Military||Air forces · Aircraft weapons · Missiles · Unmanned aerial vehicles (UAVs) · Experimental aircraft|
|Notable incidents |
|Military aviation · Airliners · General aviation · Famous aviation-related deaths|
|Records||Flight airspeed record · Flight distance record · Flight altitude record · Flight endurance record · Most produced aircraft|