Convair B-58 Hustler
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| B-58 Hustler | |
|---|---|
 |
|
| B-58A in flight, June 1967 | |
| Role | Strategic bomber |
| Manufacturer | Convair |
| First flight | 11 November 1956 |
| Introduction | 15 March 1960 |
| Retired | 31 January 1970 |
| Primary user | United States Air Force |
| Number built | 116 |
| Unit cost | |
The introduction of highly accurate Soviet surface-to-air missiles forced the B-58 into a low-level penetration role that severely limited its range and strategic value, and it was never employed to deliver conventional bombs. This led to a brief operational career between 1960 and 1970, when the B-58 was succeeded by the smaller, swing-wing FB-111A.
Contents
Design and development
Building on Convair's experience of earlier delta-wing fighters, beginning with the XF-92A, a series of GEBO II designs were developed, initially studying swept and semi-delta configurations, but settling on the delta wing planform. The final Convair proposal, coded FZP-110, was a radical two-place, delta wing bomber design powered by General Electric J53 engines. The performance estimates included a 1,000 mph (1,600 km/h; 870 kt) speed and a 3,000 statute mile (4,800 km; 2,600 nmi) range.[5]
The resulting B-58 design was the first "true" USAF supersonic bomber program. The Convair design was based on a delta wing with a leading-edge sweep of 60° with four General Electric J79-GE-1 turbojet engines, capable of flying at twice the speed of sound. Although its large wing made for relatively low wing loading, it proved to be surprisingly well suited for low-altitude, high-speed flight. It seated three (pilot, bombardier/navigator, and defensive systems operator) in separated tandem cockpits. Later versions gave each crew member a novel ejection capsule that made it possible to eject at an altitude of 70,000 ft (21,000 m) at speeds up to Mach 2 (1,320 mph/2,450 km/h). Unlike standard ejection seats of the period, a protective clamshell would enclose the seat and the control stick with an attached oxygen cylinder, allowing the pilot to continue to fly even "turtled up" and ready for immediate egress. The capsule would float, and the crewmember could open the clamshell, using it as a life raft.[8] In an unusual test program, live bears and chimpanzees were successfully used to test the ejection system.[9] The XB-70 would use a similar system (though using capsules of a different design).
The pilot's cockpit was fairly conventional for a large multiengine aircraft.[10] The electronic controls were ambitious and advanced for the day. The navigator and DSO's cockpits featured wraparound dashboards with warning lights and buttons, and automatic voice messages and warnings from a tape system were audible through the helmet sets. Research during the era of all-male combat aircraft assignments revealed that a woman's voice was more likely to gain the attention of young men in distracting situations. Nortronics Division of Northrop Corporation selected actress and singer Joan Elms to record the automated voice warnings. To the men flying the B-58, the voice was known as "Sexy Sally."[11][12]
The Sperry AN/ASQ-42 bombing/navigation system combined sophisticated inertial navigation with the KS-39 astro-tracker to provide heading reference, the AN/APN-113 Doppler radar to provide ground velocity and windspeed data, a search radar to provide range data for bomb release and trajectory, and a radio altimeter.[13] The AN/ASQ-42 was estimated to be 10 times more accurate than any previous bombing/navigation system.[13]
Defensive armament consisted of a single 20 mm (0.79 in) T-171E-3 rotary cannon with 1,200 rounds of ammunition.[13] It was remotely controlled by the DSO through the Emerson MD-7 fire control radar system.[13] Offensive armament typically consisted of a single nuclear weapon, along with fuel tanks, in a streamlined MB-1C pod under the fuselage. Incurable difficulties with fuel leakage resulted in the replacement of the MB-1C with the TCP (Two Component Pod), which placed the nuclear weapon in an upper section while the lower fuel component could be independently jettisoned.[14] This had the added benefit of allowing the pilot to "clean up" the aircraft for fuel efficiency or in case of emergency, while still retaining the (somewhat) more slim weapon.
The first prototype, serial number 55-660, was completed in late August 1956.[15] The first flight took place in November 1956.[16] A difficult and protracted flight test program involving 30 aircraft continued until April 1959.[17] The final B-58 was delivered in October 1962.[17]
From 1961 to 1963, the B-58 was retrofitted with two tandem stub pylons under each wing root, adjacent to the centreline pod,[18] for B43 or B61 nuclear weapons for a total of five nuclear weapons per aircraft. Although the USAF explored the possibility of using the B-58 for the conventional strike role, it was never equipped for carrying or dropping conventional bombs in service. A photo reconnaissance pod, the LA-331, was also fielded. Several other specialized pods for ECM or an early cruise missile were considered, but not adopted. The late 1950s WS-199C High Virgo air-launched ballistic missile was designed to be launched from the B-58 with four test launches of the High Virgo carried out by a B-58 to determine ballistic missile and anti-satellite system capability.[19]
Operational history
In addition to its much smaller weapons load and more limited range than the Boeing B-52 Stratofortress, the B-58 had also been extremely expensive to acquire. Through FY 1961, the total cost of the B-58 program was $3 billion.[22] A highly complex aircraft, it also required considerable maintenance, much of which required specialized equipment and ground personnel.
The B-58 also cost three times as much to operate as the B-52.[23] This included special maintenance issues with the nose landing gear, which retracted in a complicated fashion to avoid the center payload. Further compounding these issues, the B-58 had an unfavorably high accident rate: 26 B-58 aircraft were lost in accidents, 22.4% of total production. Most notably, the B-58 was very difficult to safely recover from the loss of an engine at supersonic cruise due to differential thrust. The SAC senior leadership had been dubious about the type from the beginning, although its crews eventually became enthusiastic about the aircraft, and while its performance and design were exceptional and appreciated, it was never easy to fly.
Two SAC bomb wings operated the B-58 during its operational service: the 43d Bombardment Wing, based at Carswell AFB, Texas from 1960 to 1964, and Little Rock AFB, Arkansas from 1964 to 1970; and the 305th Bombardment Wing, based at Bunker Hill AFB (later Grissom AFB), Indiana from 1961 to 1970. The 305th also operated the B-58 combat crew training school (CCTS), the predecessor of USAF's current formal training units (FTUs).
By the time the early problems had largely been resolved and SAC interest in the bomber had solidified, Secretary of Defense Robert McNamara decided that the B-58 was not going to be a viable weapon system. It was during the B-58's introduction that high-altitude Russian surface-to-air missile (SAM) became a viable threat, especially the SA-2 Guideline, a SAM system the Soviet Union extensively deployed. The "solution" to this problem was to fly at low altitudes, minimizing the radar line-of-sight and minimizing exposure time.
Because of the denser air at low altitudes, the B-58 could not fly at supersonic speeds and its moderate range was reduced further, thereby negating the high speed performance the design paid so dearly for. In late 1965, Secretary McNamara ordered the B-58's retirement by 1970. Despite efforts of the Air Force to earn a reprieve, the phaseout proceeded on schedule. The last B-58s were retired in January 1970 and placed in storage in AMARC at Davis-Monthan Air Force Base. The fleet survived until 1977, when nearly all remaining aircraft were sold to Southwestern Alloys for disposal.[25] The B-58 as a weapons system was replaced by the FB-111A, designed for low-altitude attack, more flexible with the carriage of conventional weapons, and less expensive to produce and maintain.
A total of 116 B-58s were produced: 30 trial aircraft and 86 production B-58A models. Most of the trial aircraft were later upgraded to operational standard. Eight were equipped as TB-58A training aircraft.
A number of B-58s were used for special trials, including testing the radar system intended for the Lockheed YF-12 interceptor. Several improved (and usually enlarged) variants, dubbed B-58B and B-58C by the manufacturer, were proposed but never built.
Singer John Denver's father, Colonel Henry J. Deutschendorf, Sr., USAF, held several speed records as a B-58 pilot.[26]
Variants
- XB-58: Prototype. Two built.
- YB-58A: Pre-production aircraft, 11 built.
- B-58A: Three-seat medium-range strategic bomber aircraft, 86 built.
- TB-58A: Training aircraft, eight conversions from YB-58A.
- NB-58A: This designation was given to a YB-58A, which was used for testing the J93 engine. The engine was originally intended for the North American XB-70 Valkyrie Mach 3 bomber.
- RB-58A: Variant with ventral reconnaissance pod, 17 built.
- B-58B: Unbuilt version. SAC planned to order 185 of these improved bombers; canceled due to budgetary considerations.
- B-58C: Unbuilt version. Enlarged version with more fuel and 32,500 lbf (145 kN) J58, the same engine used on the Lockheed SR-71. Design studies were conducted with two and four engine designs, the C model had an estimated top speed approaching Mach 3, a supersonic cruise capability of approximately Mach 2, and a service ceiling of about 70,000 ft (21,300 m) along with the capability of carrying conventional bombs. Convair estimated maximum range at 5,200 nautical miles (6,000 mi; 9,600 km). The B-58C was proposed as a lower cost alternative to the North American XB-70. As enemy defenses against high-speed, high-altitude penetration bombers improved, the value of the B-58C diminished and the program was canceled in early 1961.[27]
Operators
United States Air Force
- 43d Bombardment Wing - Carswell AFB, Texas (1960-1964); Little Rock AFB, Arkansas (1964-1970)
-
- 63d Bombardment Squadron, Medium
- 64th Bombardment Squadron, Medium
- 65th Bombardment Squadron, Medium
- 3958th Operational Test and Evaluation Squadron (1958-1960)
- 305th Bombardment Wing - Bunker Hill (later Grissom AFB), Indiana (1961-1970)
-
- 364th Bombardment Squadron, Medium
- 365th Bombardment Squadron, Medium
- 366th Bombardment Squadron, Medium
- Air Force Flight Test Center - Edwards AFB, California (1956-58)
- 6592d Test Squadron
Aircraft on display
- TB-58A
- 55-0663 - Grissom Air Museum, Grissom Air Reserve Base (former Bunker Hill AFB/former Grissom AFB), Peru, Indiana. This is the oldest remaining aircraft and the fourth B-58 built.[28]
- 55-0668 - Little Rock Air Force Base in Jacksonville, Arkansas.[29]
- YB-58A
- 55-0665 (Snoopy) - Edwards Air Force Base, California. This aircraft is utilized as a photo target on the Edwards AFB range and is in extremely poor condition.[30]
- 55-0666 - Octave Chanute Aerospace Museum (former Chanute AFB), Rantoul, Illinois.[31]
- B-58A
- 59-2437 (Firefly II) - Lackland AFB/Kelly Field Annex (former Kelly Air Force Base), San Antonio, Texas.[32]
- 59-2458 (Cowtown Hustler) - National Museum of the United States Air Force, Wright-Patterson Air Force Base, Dayton, Ohio. This aircraft flew from Los Angeles to New York and back on 5 March 1962, setting three separate speed records, and earning the crew the Bendix Trophy and the Mackay Trophy for 1962. The aircraft was flown to the Museum on 1 March 1969. The aircraft is on display in the Museum's Cold War gallery.[33]
- 61-2059 (Greased Lightning) - Strategic Air and Space Museum near Ashland, Nebraska. It averaged 938 nmph flying 8,028 nmi. from Tokyo to London in 8 hr, 35 min.[34]
- 61-2080 - Pima Air & Space Museum (adjacent to Davis-Monthan Air Force Base) in Tucson, Arizona. It was the last B-58 to be delivered.[35]
Specifications (B-58A)
Original combined expendable underbelly fuel and weapon pod
A front view of the B-58A in the "clean" configuration
Cutaway diagram of the J79 with components labeled
Cutaway of an air start system of a General Electric J79 turbojet. The small turbine and epicyclic gearing are clearly visible.
Data from Quest for Performance[36]
General characteristics- Crew: 3: pilot; observer (navigator, radar operator, bombardier); defense system operator (DSO; electronic countermeasures operator and pilot assistant).
- Length: 96 ft 10 in[37] (29.5 m)
- Wingspan: 56 ft 9 in[37] (17.3 m)
- Height: 29 ft 11 in (8.9 m)
- Wing area: 1,542 ft² (143.3 m²)
- Airfoil: NACA 0003.46-64.069 root, NACA 0004.08-63 tip
- Empty weight: 55,560 lb (25,200 kg)
- Loaded weight: 67,871 lb (30,786 kg)
- Max. takeoff weight: 176,890 lb (80,240 kg)
- Powerplant: 4 × General Electric J79-GE-5A turbojet
- Zero-lift drag coefficient: 0.0068
- Drag area: 10.49 ft² (0.97 m²)
- Aspect ratio: 2.09
- Maximum speed: Mach 2.0[37] (1,319mph) at 40,000 ft (12,000 m)
- Cruise speed: 610 mph (530 kn, 985 km/h)
- Combat radius: 1,740 mi (1,510 nmi, 3,220 km)
- Ferry range: 4,100 nmi (4,700 mi, 7,600 km)
- Service ceiling: 63,400 ft (19,300 m)
- Rate of climb: 17,400 ft/min (88 m/s) at gross weight[38]
- Wing loading: 44.0 lb/ft² (215 kg/m²)
- Thrust/weight: 0.919 lbf/lb
- Lift-to-drag ratio: 11.3 (without weapons/fuel pod)
- Guns: 1× 20 mm (0.79 in) T171 cannon[37]
- Bombs: 4× B43 or B61 nuclear bombs; maximum weapons load was 19,450 lb (8,820 kg)
- AN/APB-2 Bombing radar[39]
- AN/APN-110 Doppler navigational radar[40] (part of Sperry AN/ASQ-42 Navigation & Bombing System)[41]
- AN/APN-170 Terrain-following radar[40]
- AN/APR-12 Radar warning receiver[42]
- Hughes Aircraft AN/APQ-69 podded side-looking aperture radar (mounted on RB-58A)[43]
- Goodyear AN/APS-73 podded synthetic aperture radar (mounted on RB-58A)[42]
Notable appearances in media
Jimmy Stewart, a bomber pilot during World War II and the early cold war period, made a film for the Air Force, flying in the back seat of the B-58 on a typical low-altitude attack in the film B-58 Champion of Champions.The B-58 has also appeared in the 1964 film Fail-Safe, where stock footage of B-58s was used to represent the fictional "Vindicator" bombers which attacked Moscow. Interestingly, the art used in the original magazine publication of the novel had depicted the "Vindicator" bombers—itself the recycling of the name of a World War II American dive bomber—as almost identical to B-58s but equipped with canards.[44]
In Fail Safe, a 2000 made-for-TV remake starring George Clooney, the fictional Vindicator bomber was again represented by the B-58 Hustler.
See also
- Related development
- Aircraft of comparable role, configuration and era
- BAC TSR-2
- Boeing XB-59
- Dassault Mirage IV
- Myasishchev M-50
- North American A-5 Vigilante
- Tupolev Tu-22 'Blinder'
- Related lists
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