North American B-45A Tornado

Last revised December 30, 2007

The first production model of the Tornado was the B-45A (NA-147). It differed from the XB-45 in featuring improved ejection seats for the pilot and co-pilot and had safer emergency exits for the bombardier/navigator and the tail gunner. An E-4 automatic pilot was fitted. A bombing navigation radar and an A-1 fire control system were provided. Communication equipment, emergency flight controls, and copilot instrumentation were improved. Since the radar gun direction system originally planned for the Tornado was not yet perfected, a tail gunner's cockpit was provided for the aiming of the two 0.50-inch machine guns in the tail. A total of 1200 rounds of ammunition was provided for the tail guns.

Some of the B-45As were fitted with the AN/APQ-24 bombing/navigation radar system and were fitted with electronic countermeasures equipment such as the AN/APT-5.

The first production B-45A flew on February 24, 1948. The Air Force started taking delivery of the initial batch of 22 B-45A-1-NA aircraft in April of 1948. These were initially powered by four J35-A-11 engines, since the J47 engines were not yet ready.

The B-45A-1-NA was not considered as being combat-capable and most of them were assigned to training duties or to various test programs. Some of them became known as TB-45A-1-NA in recognition of their training role, but a few TB-45s were later brought up to combat configuration.

The next batch of Tornados, B-45A-5-NA, were equipped with more powerful J47 engines (either two J47-GE-7s or two J47-GE-13s, and two J47-GE-9s or two J47-GE-15s).

The first B-45As went into service in November 1948 with the 47th Bombardment Group based at Barksdale AFB in Louisiana. Despite slippages, 96 B-45As were completed by March of 1950

However, in the fiscal year 1949, there was a severe budgetary crunch which caused numerous defense appropriations to be severely cut back or cancelled outright. The B-45 was not to escape some of the cuts. According to original plans, five light bomb groups and 3 light tactical reconnaissance squadrons were to be equipped with Tornados. However, under the proposed fiscal 1950 budget, only one light bomb group and one light tactical reconnaissance squadron were to be equipped with Tornados. This meant that either the procurement of B-45s would have to be cut back or else substantial numbers of B-45s would have to placed in storage upon completion. Neither option was attractive, but the Aircraft and Weapons Board decided to cancel 51 of the 190 B-45 aircraft on order.

The early B-45As delivered to the USAF were not truly operational. They had no fire control bombing equipment, and they did not have suitable bombsights. Structural weaknesses such as cracked forgings had been noted in some aircraft, especially in those that had attempted violent low-altitude maneuvers. The new J47 engines had serious maintenance problems and had to be inspected after only 7 1/2 hours in the air and could be flown only 7 1/2 hours more before requiring a complete overhaul. There was insufficient money to purchase enough spare engines to ensure that the B-45s could be kept flying, and the F-86 Sabre had first priority for the J47.

The last of 96 B-45As was delivered to the Air Force in March of 1950.

The B-45 encountered severe operational difficulties. High speeds affected the gyrocompass adversely, and the E-4 automatic pilot frequently failed when the bomb doors were open. The emergency brake was unreliable. Bomb shackles would often become unhooked during certain maneuvers. Engines would often catch fire when first started because of an improper aspirator system. The airspeed indicator was often inaccurate, and the fuel pressure gauges were erratic. Those B-45s with the AN/APQ-24 bombing/navigation radar system had their own special problems. The AN/APQ-24 was a maintenance nightmare, and spare parts were in short supply. Malfunctions of the pressurization pump limited the altitude at which the system could operate. The radar antenna was not properly positioned, which limited the coverage of targets. In addition, the combat radius and the ferry range were too short.

Some of the late production B-45As were converted to B-45C configuration in an effort to extend their service life and to correct some of the problems encounted with the initial production version. These changes included the fitting of a stronger greenhouse-type segmented canopy, and the wingtips were modified so that they could carry 1200-gallon tanks that could be dropped in flight if necessary.

At one time, the Air Force had planned to transfer the 47th Group's B-45 Tornados to the Far East Air Force, based in Japan. However, the B-45 had insufficient range to reach Hawaii (the B-45A-1-NA had a ferry range of only 2120 miles) and the aircraft was too large to be loaded aboard Liberty or Victory ships without removing ten feet from each of the wings. Consequently, the deployment of the B-45A to the Far East was deemed impractical.

The outbreak of the Korean War in 1950 led to a decision to adapt the B-45 to the tactical nuclear role as a deterrent against a Soviet attack against western Europe. However, the B-45 had not originally been designed with the delivery of atomic bombs in mind. Because of the high degree of secrecy surrounding the nuclear bomb program, the North American engineers did not even know the dimensions of the early nuclear weapons, and it turned out that the B-45 bomb bay could not accommodate the first atomic bombs because of a large spar that extended across the width of the bomb bay. Expensive and time-consuming modifications would be needed to make the B-45 capable of carrying these bombs. The development of smaller and lighter atomic bombs in the later 1940s helped somewhat, but their development was also accompanied by excessive secrecy, and the B-45 could not carry these bombs either without extensive modifications.

In December 1950, the Air Staff decided to go ahead and direct AMC to modify B-45s for atomic duty. The program started with 9 aircraft--five of them would be equipped with the AN/APQ-24 system, and four with the AN/APN-3 Shoran navigation and bombing system plus the M9C Norden bombsight. Other B-45s were later added to the modification program. The bomb bay had to be structurally modified to handle three different types of atomic bombs, and a large amount of electronics support equipment had to be added. The aircraft had to be fitted with a new defensive system and extra fuel tanks. Modification work was done at the AMC Depot facility at San Bernardino, CA. The last aircraft was modified in April of 1952. The program was known as Backbreaker, and the planes were to go to the 47th Bombardment Wing based at RAF Sculthorpe in the United Kingdom.

The first nuclear-capable B-45As began to reach the United Kingdom in May of 1952, and by mid-June 40 aircraft were deployed. The tail defense system was upgraded, and the fuel flow totalizer (which had not been installed in the first 40 Backbreaker B-45s because of production delays) needed to be added. One specific type of atomic bomb required that the supports be moved into the forward bay to allow the installation of a 1200-gallon fuel tank in the rear bay. This program was not completed until March of 1954.

Four B-45A squadrons ended up serving in Europe during the early 1950s as the Strategic Air Command's first-line deterrent.

The B-45As rapidly became obsolescent as the B-47 Stratojet began to enter service. The B-45A began to be phased out of service beginning in the mid-1950s, and by January 1958, less than 50 were still operational. The B-45As with the 47th Bomb Wing (Tactical) rapidly converted to the Douglas B-66 Destroyer, and by July of 1958, the B-45s in the United Kingdom had all been transferred to other bases in Europe and North Africa. Most were junked there and sold for scrap.

Some of the early B-45As powered by Allison engines were used for training purposes under the designation TB-45A. Some of them were used as target tugs with a hydraulically-controlled reel and cable system in the bomb bay for a 20-foot Chance Vought target glider. A few of them were later brought up to the Backbreaker configuration.

The DB-45A was a conversion that was used as a director in guided weapons development.

The last production B-45A (47-096) was modified for use as an inflight engine testbed and was redesignated JB-45A. The test engine was attached to a retractable pylon mounted inside the modified bomb bay. Once airborne, the test engine was lowered into the slipstream and was started.

A Tornado marked as B-45A 47-008 is on display at the Castle AFB museum in California. However, it has the reinforced canopy of the later B-45C. The canopy was changed either during its service as a Navy drone controller or when the aircraft was brought from China Lake Naval Weapons Center to Castle for restoration. It was brought in pieces and reassembled at Castle.

Serials of B-45A:

47-001/022 	North American B-45A-1-NA Tornado 
			008 on display at Castle AFB Museum 
47-023/096 	North American B-45A-5-NA Tornado 
47-097 		Static test airframe for B-45A Tornado 

Specification of North American B-45A Tornado:

Engines: Four General Electric J47-GE-13/15 each rated at 5200 Alternatively, four J47-GE-7/9 engines were provided. Performance: Maximum speed 571 mph at 3500 feet, 503 mph at 37,000 feet. Cruising speed 470 mph at 35,000 feet. Stalling speed 125 mph. Initial climb rate 5950 feet per minute. Combat ceiling 42,800 feet. Service ceiling 46,400 feet. Combat radius 533 miles with 10,000 pound bombload. Takeoff ground run 3400 feet. Takeoff over 50 foot obstacle 4930 feet. Dimensions: Wingspan 89 feet 0 inches, length 75 feet 4 inches, height 25 feet 2 inches, wing area 1175 square feet. Weights: 45,694 pounds empty, 81,418 pounds gross. Armament: two 0.50-inch M-3 machine guns in tail turret. Maximum bomb load 22,000 pounds. Could carry 27 500-lb bombs in two bays for a distance of 800 miles or a single 22,000-lb Grand Slam bomb, or two 4000-lb nuclear bombs.


  1. American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.

  2. Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.

  3. McDonnell Douglas Aircraft Since 1920: Volume I, Rene J. Francillon, Naval Institute Press, 1988.

  4. Big Bodies in Motion--Flying the Best of SAC's Bombers, Howard S. Myers, Jr., Wings, August 1995.

  5. E-mail from Charles Sill on the B-45A on display at Castle Air Museum.

  6. E-mail from Daniel Wilson on Backbreaker program.

  7. USAF Museum website,