The B-58 Hustler was a true icon of the Jet Age, with its polished aluminium skin, a futuristic design and the ability to carry multiple nuclear bombs into the Soviet Union at Mach 2.
A massive technological undertaking, the B-58 was a marvel of engineering for its day. It first flew just a decade after the end of WWII.
However for all of its impressive looks and specifications, the B-58 was marred with trouble, virtually from the outset. A terrifyingly high-crash rate and the massive costs involved with operating a Mach 2 bomber would result in its demise.
The pace of technical development in military aviation during World War Two was hectic. Every major nation began that conflict with conventional piston-engine fighters and bombers. By the end of the war, the first jet fighters and bombers were in service and even the first rocket fighters had seen operational use.
But in the ten years following the war, the pace of change became frenetic, with east and west vying to produce aircraft that could fly faster and higher than ever before.
The Convair B-58 Hustler had its origin in that period when anything seemed possible and each new generation of combat aircraft brought staggering advances in performance.
In 1945, the front-line bomber of the US 8th Air Force was the Boeing B-17G Flying Fortress, capable of a cruising speed of 180mph while carrying a bomb load of 4,500lbs of bombs.
Just seven years later, in 1952, Convair unveiled a mock-up of a new delta-wing jet bomber designed to cruise at supersonic speed while carrying nuclear weapons.
Convair began a design study on the feasibility of a delta-wing supersonic intercontinental bomber as early as October 1946 with the Generalized Bomber Study (GEBO), funded by the USAAF.
The delta-wing configuration was felt to offer significant advantages at extreme speed and Convair were the only US aircraft manufacturer who had produced a delta-wing military aircraft, the XF-92 interceptor.
This never entered production, but it did provide Convair with valuable data on the performance of delta-wing aircraft.
Convair studied, literally, thousands of possible configurations before announcing an extremely advanced concept in late 1950: this involved a parasite bomber that would be carried into the air beneath a B-36 bomber.
The parasite aircraft was a small, two seat bomber powered by two non-afterburning General Electric J53-GE-X25 turbojet engines and was planned to be able to cruise at supersonic speed and reach and altitude of 50,000 feet.
Rather than a bomb bay, the aircraft carried a jettisonable bomb pod under its fuselage. The US Air Force liked the design of the supersonic bomber, but not the parasite concept: it was felt that this would be expensive to produce and maintain and might be vulnerable to enemy attack while the two aircraft were conjoined.
In December 1951, the design was refined as a stand-alone delta-wing bomber powered by two afterburner-equipped turbojet engines and providing space for a crew of three: a pilot, a navigator/bombardier and a defence systems operator.
The new design retained the jettisonable bomb pack carried under the fuselage and included the ability for in-flight refuelling. To dissipate the heat generated by high-speed flight, the aircraft’s skin was a novel sandwich of honeycombed fiberglass between outer aluminium and steel plates.
Rather than being rivetted, which was the standard approach at that time, these plates were glued together. Further modifications to the design were undertaken and when a mock-up was revealed in late 1952, if featured four General Electric J79-GE-1 turbojets in pods under the wings which featured sweep-back of 60˚.
In December 1952, the new aircraft was given the designation B-58 and the name Hustler.
Generally, new aircraft ordered by the US Air Force are produced as prototypes and these are extensively tested to refine the design before the new aircraft goes into volume production.
Such was the urgency with which this project was viewed that it was agreed to skip the prototype phase: the first 30 B-58 aircraft off the production line would be used for testing and to resolve any problems. This was a risky decision for an aircraft of such radical design.
By August 1954, the design had matured into its final configuration. The engines were mounted in four separate pods beneath the wings, the fuselage was redesigned according to the new modified transonic area rule for supersonic speeds (leading to the “coke-bottle” shape) and the bomb pack was shortened and modified to contain fuel as well as the bomb load.
The bomb pod could also be replaced with a photo-reconnaissance pod including a Fairchild KA-56 panoramic camera. Due to the B-58s speed, the only defensive armament was a single General Electric M61 Vulcan 20 mm rotary cannon in the tail, remotely-controlled by the Defensive Systems Officer.
In December 1955, a contract was issued by the US Air Force for an initial production run of 13 aircraft and 31 bomb/photo-reconnaissance pods.
The first B-58s were handed over to the US Air Force in 1960, and it soon became apparent that the new aircraft had truly phenomenal performance. It was the first supersonic bomber and the first bomber to reach Mach 2, making it faster than most fighters in service at the time. It was able to fly above the range of most Russian Surface-to-Air Missiles (SAMs).
It also climbed like a rocket (it could dash-climb to 85,000 feet) and was as manoeuvrable as many smaller, lighter, aircraft. B-58s quickly set a number of speed and altitude records. One B-58 flew from Los Angeles to New York and back in under five hours. Another flew non-stop from Tokyo to London and maintained an average speed of over 1,000mph.
In service, it also quickly became apparent that the B-58’s composite skin and small size made it very difficult to detect on the radar equipment available in the 1960s.
The Cost of Cutting Edge
On paper, the B-58 looked like the first of the next generation of combat aircraft. From the cockpit, things looked less impressive. Its stall and spin characteristics were unforgiving and maintaining the correct angle of attack was critical at all stages of flight.
Pilots had to fly the B-58, with extreme care, from the moment it began to taxi until engines were finally switched off. Inherently challenging flight characteristics were exacerbated by unresolved design issues.
For example, losing the power of an engine at high speed could cause the aircraft to yaw so severely that it could break-up in flight.
The fuel transfer system was also eccentric and not always reliable. A failure of this system while at high speed presented the crew with an unpleasant decision: bale out at supersonic speed, which they were unlikely to survive, or allow the aircraft to slow but then its changed centre of gravity might make it uncontrollable at subsonic speed.
The first B-58 crashes happened even before the aircraft was handed over to the US Air Force. In December 1958, a B-58 on a test flight was lost following an electrical problem which caused a loss of control. The pilot was killed but both other members of crew survived.
In November 1959 a B-58 being flown by a Convair civilian crew out of Carswell AFB crashed during a test-flight, killing both crewmembers (no Defensive Systems Officer was carried on this flight). An accident investigation suggested that fuel transfer problems had made the aircraft unstable in flight.
Four months later, another B-58 on a test flight out of Carswell AFB broke up in the air after a loss of control during normal flight. One of the crew was killed but the other two survived ejection.
In April 1960 another B-58 suffered structural damage after encountering a hailstorm while at supersonic speed.
All three civilian crew members were killed. All four of these crashes involved very experienced test pilots and crews and ominously, two involved a “loss of control in normal flight.” It was clear even at this early stage that the B-58 was a very challenging aircraft to fly, and the accident rate increased when the first B-58s were handed over to the US Air Force.
In June 1961, a B-58 named The Firefly set a new speed record for a flight between New York and Paris. A few days later, the same aircraft (with a different crew) was performing low-level aerobatic manoeuvres in front of a large crowd attending the Paris Air Show.
The pilot appeared to lose control after entering low cloud and the aircraft crashed close to Le Bourget airport, killing all three crew members. In June 1965, another B-58 was scheduled to take part in the Paris air show.
It arrived late and carrying more fuel than anticipated. The pilot was given the option of making an immediate heavy landing or diverting to another airport.
He chose the former option and the B-58 undershot and crashed short of the runway, killing the pilot. The other two crew members survived.
These two very public crashes were only the tip of the iceberg. In all, 116 B-58s were delivered to the US Air Force. Twenty-six were lost to crashes, a loss rate of 22% over the ten years that the B-58 was in service that caused the death of 36 US Air Force personnel.
This loss rate was higher than almost any other US combat aircraft, but it wasn’t its fearsome reputation for crashes that finally doomed the B-58. One significant problem was cost: it was estimated that the US Air Force could operate six wings of B-52 bombers for the same cost as just two wings of B-58s.
But what really killed the B-58 was something that happened just as it was entering service.
Speed and Height Were No Longer an Option
Since 1958, CIA pilots had been flying U2 reconnaissance aircraft over the Soviet Union. This aircraft was capable of flying at 70,000 feet, well above the range of Russian SAMs or interceptors.
Then, on 1st May 1960, Francis Gary Powers was shot down in a U2 over Russia by a new S-75 Dvina (NATO name, SA-2 Guideline) SAM. Suddenly, it became clear that the altitude at which the B-58 could fly would not make it safe from Soviet Air Defences.
In addition, the first Intercontinental Ballistic Missiles (ICBMs) became operational in 1959 and the first Submarine Launched Ballistic Missiles (SLBMs) in 1960. US Air Force Strategic Air Command began to consider whether these missiles were a more effective way of delivering nuclear weapons to hostile territory than conventional bombers?
Just as it entered service, the very role for which the B-58 had been designed began to seem irrelevant.
The specialized nature of its design also made it difficult to use the B-58 in other mission types. In contrast its contemporary the B-52, also designed as a nuclear bomber, proved to be a very effective conventional bomber.
From 1966, B-52s were dropping 8,000 tons of bombs every month in support of US forces in Vietnam. The specialised high-altitude, high speed B-58 simply wasn’t suitable for such missions, though in 1967, the US Air Force did undertake testing of the B-58 for low-level, conventional bombing missions.
However, the aircraft’s difficult handling made it unsuitable in this role and none were ever used in the conflict in Vietnam.
A combination of a high accident rate, changing operational circumstances, an inability to undertake non-nuclear missions, high costs and operational problems meant that the last B-58 was retired by the US Air Force in early 1970, after less than ten years in service.
This was a bold design intended to fulfil a particular niche in bombing requirements. However, the introduction of more effective Soviet air defence capabilities plus the arrival of ICMBs and SLBMs just as the Hustler entered service removed the operational need it was designed to fulfil. By the time that it entered service, the B-58 was the answer to a question non-one was asking.
- Crew: Three
- Length: 96 ft 10 in (29.51 m)
- Wingspan: 56 ft 9 in (17.30 m)
- Height: 29 ft 11 in (9.12 m)
- Wing area: 1,542 sq ft (143.3 m2)
- Empty weight: 55,560 lb (25,202 kg)
- Max takeoff weight: 176,890 lb (80,236 kg)
- Powerplant: 4 × General Eletric J79-GE-5A afterburning turbjojet, 10,400 lbf (46 kN) thrust each dry, 15,000 lbf (67 kN) with afterburner
- Maximum speed: 1,146 kn (1,319 mph, 2,122 km/h) at 40,000 ft (12,000 m)
- 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)
- Guns: 1× 20mm T171 Cannon
- Bombs: 1× Mark 39or B53 or 4× B43 or B61 Nuclear bombs; maximum weapons load was 19,450 lb (8,822 kg)