Speed Freak- page 2 | History | Air & Space Magazine
Convair B-58A Hustler in flight. (US Government)

Speed Freak

In the 1950s, the Mach 2+ B-58 Hustler seemed a safe bet to win the arms race

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(Continued from page 1)

The B-58, however, was not the unanimous choice within the leadership of the Strategic Air Command to fill that role. SAC commander Curtis LeMay wanted to start over with a different design. The project limped along with the support of the Air Research and Development Command.

“The B-58 is a major advance, considering that we are attempting to more than double our speed capabilities. For that reason, I believe that it has a place in the Air Force inventory,” argued Major General Albert Boyd in a 1951 progress report to Lieutenant General Thomas Power, then ARDC commander. “Since we are attempting such a major advance, there is very naturally a high degree of risk.”

One of the most significant technological advances was Convair’s designing the fuselage with the use of area rule, which the company first used on the F-102 supersonic interceptor. Developed by Richard T. Whitcomb of the National Advisory Committee for Aeronautics’ Langley Field Laboratory, the area rule resulted in a “Coke bottle” shape, greatly reducing aerodynamic drag along the fuselage and wing section at both transonic and supersonic speeds—the lower the drag, the higher the speed. It took Convair several tries and the help of NACA aerodynamicist R.T. Jones to design the fuselage.

The B-58’s shapely fuselage housed a unique crew configuration. Each of the three crew members—a pilot, a navigator/bombardier, and a defensive systems operator—was housed in his own compartment. Separated by banks of equipment, the crew members had no physical contact with one another, although the crew could pass notes via a string-and-pulley system that ran along the cabin wall.

The B-58’s bullet-like speed was both a blessing and a curse to its three-man crew. The speed made the aircraft nearly impossible to pursue. But should a catastrophic airframe or system failure occur, a standard ejection at Mach 2 would be unsurvivable. Despite this fact, the first B-58s had only standard, rocket-propelled ejection seats, and the use of them resulted in several deaths. In 1962, common sense finally prevailed, and the B-58s were retrofitted with an encapsulated ejection system (see illustration, p. 68).

While the escape pod was the only way to attempt an ejection at Mach 2, some crew members were not sold on the capsule’s value. “Our crew was dispatched to pick up the first production aircraft with the capsules installed,” recalls Howard Bialas, a B-58 defensive systems operator from 1958 to 1965, the first person to accrue 1,000 hours in the bomber. He was also a member of a crew who set three world speed records in the B-58 in 1961. “We were more than hesitant to crawl into it. There was no reason to use it at Mach 2. If a structural failure occurred, you would never be able to pull the handles. And if deceleration [from an engine failure] was necessary, just hang on, [you] would be subsonic in a few seconds. Deceleration was much more rapid than acceleration. We didn’t sweat Mach 2 before we got the capsules, so why after?”

Although the escape capsule was credited with saving a number of crew members, Bob Norton, who flew the B-58 out of Bunker Hill Air Force Base in Indiana, remembers one instance in which it contributed to a fatal crash. “One of our guys was flying in western Texas and some hail blew the windshield out. He encapsulated himself—you could still fly the airplane with the capsule closed but you could not control the throttles. Anyway, when the windshield blew, he pulled the throttles to idle before he closed the capsule. The trouble was, he couldn’t get [the capsule] open again when the hail stopped,” he says. “With the throttles pulled back, he was going down, so he told the other crew members to bail out. Unfortunately, the navigator’s parachute didn’t deploy and he was killed. After that they installed a cable so the pilot could quickly pull the pod open in flight.”

The B-58’s wings had to have a very high strength-to-weight ratio to handle high speeds at low altitudes. “That thin wing and the delta sweep made going through the sound barrier like slicing a piece of cheese,” says Chana. “It would penetrate the sound barrier without any shaking or anything.”

Convair’s engineers used a new honeycomb sandwich design to achieve the high strength and low weight they needed. Sections of fiberglass honeycomb were sandwiched between aluminum panels and then bonded to the wing’s frame using temperature-resistant adhesives. Molding the honeycomb panels was a painstaking process, resulting in structures that were rigid and resilient—necessary traits for a wet wing holding 65,000 pounds of fuel.

The Hustler’s external pod was an integral part of its aerodynamic design. The pod comprised interchangeable compartments for weaponry, fuel, and equipment, which could be deployed separately or together. During the design phase, the configuration proved to have disadvantages as well—every time designers wanted to make a change to the airframe, they had to adjust the pod’s configuration too.

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