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• History of Flight

Speed Freak

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

• By Dale Smith
• Air & Space Magazine, January 01, 2006

THE DESIGN OF U.S. FRONTLINE FIGHTERS and bombers—the F-117, F-22, and B-2—is primarily based on a simple defensive strategy: If they can’t see you, they can’t shoot at you. But way back when radar was young and stealth technology was a far-off dream, the Air Force bet on a different strategy: They may see you, but they sure won’t catch you. In the 1960s, the Air Force relied on speed to penetrate enemy airspace, and the airplanes built to be uncatchable were as radical in their time as the first stealth aircraft were in the 1980s and ’90s. One of them, the Convair B-58 Hustler, looks radical even today

With its long, slender fuselage, dramatically swept delta wing, and four big engines, the B-58 looked fast even when it was on the ground. It was one of the first aircraft to take advantage of the knowledge that the way to overcome drag in supersonic flight is to sweep the wings at such an angle that the aircraft flies within the Mach cone, a three-dimensional bow wave formed around a body moving through the air at supersonic speed. When the wings are within that cone, the airflow over them remains subsonic. So successful were the Convair aerodynamicists at managing supersonic flight that on October 15, 1959, the first production Hustler flew faster than Mach 2 for more than an hour. Refueling once, the aircraft traveled 1,680 miles in 80 minutes.

The world’s first supersonic bomber inherited its delta wing from earlier Convair projects: The XF-92A was the world’s first delta wing aircraft and the foundation for Convair’s F-102, the world’s first supersonic interceptor.

Early in the development phase, engineers on the XF-92A discovered during wind tunnel tests that the highly swept, narrow-chord wing was very unstable. A Vultee aerodynamicist, Ralph Shick, suggested a solution to Adolph Burstein, chief technologist, and Frank Davis, test pilot and head of Aero and Flight Test: “Why don’t we just fill in the area between the two wing tips?” Shick hypothesized that changing to a single, triangle-shaped wing would generate more stability and control. He was right.

Although the delta wing concept first appeared during World War II in Germany, Bill Chana, a former XF-92A flight test engineer, says the XF-92A’s design was a Convair original. “A lot of people think Burstein and Shick got the delta idea from the Germans,” says Chana. “That’s just not true. Their delta wing configuration for the Convair interceptor was their own thinking.”

By early 1953, Convair had begun work on the XB-58 and XBR-58. They relied on their findings from the XF-92A program (retired in 1953) and 10,000 design configurations they explored to advise the Air Force, under a general study, of the designs that would promise the best performance for supersonic bombers.

“The original mission profile for the B-58 was to cruise to the target area at .91 Mach, then dash at Mach 2-plus above 50,000 feet for approximately 500 miles,” remembers Harold “Hal” Confer, the second Strategic Air Command pilot to be certified as operational in the B-58. “We’d drop the pod containing the nuclear weapon and return to home base at .91 Mach cruise. We could outrun and out-distance all of our fighters of that era, which certainly brought a smile to the face of this old bomber pilot.”

“When the B-58 was designed, [the Russians] hadn’t really perfected a surface-to-air-missile system and didn’t have a high-altitude supersonic fighter yet,” says Ben Baddley, a B-58 navigator/bombardier. “The B-58 was created to take advantage of that situation.”

According to Convair’s company newspaper, Convariety, the B-58 got its name, the “Hustler,” when the new aircraft’s performance was described to E. Stanton Brown, an engineering administrative supervisor. His response was “Sounds like it’ll really be a hustler....” The name stuck. At first, it was just the name used by the engineers working on the Convair program, but the Air Force eventually (and reluctantly) made it the aircraft’s official name.

“The purpose of the B-58 was to try to change the dynamics of any potential engagement with the Soviets,” says Richard P. Hallion, former Air Force historian. “The thinking was that a supersonic bomber would compress the Soviet’s response time of their interceptors, tracking and search radars, and even the time it would take for surface-to-air missiles to be properly aimed.”

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.

Despite its sophisticated hardware, the B-58’s limited range continued to hinder its acceptance into SAC’s arsenal, and the bomber was almost cancelled many times during development. Although progress with aerial refueling greatly extended the bomber’s range, SAC’s commanders continually debated the overall value of an airplane so dependent on refueling to complete its mission.

Major General John McConnell, SAC’s Director of Plans, declared that his command was interested in the development of the B-58 as a future weapon system but not for the SAC inventory. McConnell called the B-58 a “short-legged plane,” adding that “as long as Russia (and not Canada) remained the enemy, range was important.” The B-58’s range limitations would haunt it throughout its operational life.

“We do not know all the answers and will not until we have flown such an aircraft,” wrote Major General Boyd in defense of the B-58 program. “Thus, we must accept such a risk sooner or later if we are in fact ever going to achieve a truly supersonic bomber.” The people accepting the risk were the test pilots and bomber crews who tried to tame the Hustler.

The B-58 Hustler made its first flight on November 11, 1956, from the Convair facility at Carswell Air Force Base in Fort Worth, Texas. The initial flight lasted 38 minutes and was made without the pod and without the use of afterburners. It was also the first time the Hustler was introduced to the public at large. During its development, little information had been leaked about the aircraft’s technological advances. About 30,000 people watched the bomber lift off for its flight that day. The first supersonic flight took place the following month.

While it got off to a smooth enough start, the B-58’s test and development program was a rocky one: Five of the first 20 test aircraft were lost to causes ranging from structural stress to “unexplained.” Even proponents of the program believed the accident rate was due to rushing the airplane into production before it was really ready.

“I felt then, and still feel now, that the airplane flew before it should have,” says renowned test pilot Joe Cotton, a B-58 pilot for 10 years and the first to fly the XB-70 Valkyrie in 1962. “When you look at all the flight control problems, the fuel system, the landing gear and tire problems, everything we were up against—well, I always wondered if the Hustler had first flown in 1958 [instead of in 1956], we would probably have a few more fine people alive today. But I guess they could not wait when we were fighting a cold war. We were trying to push our enemy up to higher Mach numbers and push their development efforts to their limits. We were the aggressor and were pushing technology forward.”

The B-58’s complex flight control system was a cause for continual anguish; designers, pilots, and mechanics all struggled with it. Because of the delta wing configuration, the bomber had no horizontal elevators or wing-mounted ailerons. Instead, it had a very complex system of linkages that connected the wing’s elevons (a combination of ailerons and elevators) to the large rudder.

“You would sit there on the end of the runway doing all kinds of checks on the flight controls,” Cotton says. “It was an extremely complex arrangement, centered around the power control linkage assembly. When I preflighted the airplane, I made sure the crew chief had it opened up so I could look up in there to see if there were any hydraulic leaks and that the rods were all connected—the system was a hydro-mechanical-electrical maze.” Most pilots and crew members referred to it as the “three-bicycle wreck” since it looked like the engineers had run three bikes together.

“I think the flight control system led to the loss of a few people and aircraft,” Cotton says. “It took a tremendous amount of understanding. A lot of pilots would tell you that they flew the airplane a long time before they understood what they were doing when they mixed the stick around.”

Cotton also remembers the time one of his test pilots requested dismissal from the B-58 program. “He came to me and said, ‘Joe, I quit.’ I told him I didn’t hear what he said and wanted him to think about it for two or three days—we had been investigating another B-58 crash. Anyway, he came back and said that he had really made up his mind. ‘I’ve reached a point in my career,’ he told me, ‘where I can no longer control my destiny with my right hand.’ [That was certainly a] real condemnation against the Hustler’s flight control system.”

Even in its operational life, the Hustler maintained its reputation as a dangerous airplane to fly. Darrell Schmidt, a B-58 pilot from 1966 to 1970, says, “There were 116 aircraft built, 26 of which were destroyed in accidents, with 36 crew members killed. If that doesn’t fit the definition of ‘dangerous,’ I don’t know what would.”

B.J. Brown, who flew as a B-58 navigator/bombardier in the early 1960s, feels differently. “I don’t have a clue as to where the B-58 got that reputation [for being dangerous],” he says. “There were a lot of men killed in the B-47...a lot of men. And I don’t know that [the B-47] had a ‘dangerous’ stigma attached to it.”

“A racehorse is dangerous if it isn’t treated with tender loving care, and the same was true of the Hustler,” says Howard Bialas. “It was a demanding bird, requiring constant attention, but it rewarded you with experiences unknown to mere mortals. Moving through the heavens at 20 miles per minute is an awesome experience.”

The airplane’s accident rate may reflect the fact that there was no two-seat trainer for the early pilots. Confer remembers early checkout rides as being not much more than an over-the-shoulder briefing.

“[Early in] the program there were no dual-control B-58s,” wrote Confer in Daedalus Flyer, a military pilot association magazine. “After extensive ground school at the Convair plant, the first flight was a solo. At the aircraft, a test pilot would give the new pilot a briefing on the 10 ‘killer’ items in the cockpit—as in ‘Always do this; never do that; and don’t ever touch that switch—good luck!’ ”

For the most part, pilots came away from the Hustler feeling it was a machine that demanded respect and attention. “You just had to think ahead of the airplane all the time—that was the secret to it,” explains Norton. “Transition was tough because the B-58 climbed at 458 knots indicated—faster than the B-52 flew. So it took some getting used to. Those first couple of takeoffs were really exciting.

“I’d say the toughest part was landing…. You came in at 12 degrees nose up, so you really couldn’t see the runway too far ahead of you…. With a normal radar approach your touchdown point was 1,500 feet down the runway. Well, in the B-58, at the high nose-up angle, it wanted to coast down the runway, so our theoretical touchdown point was actually 2,000 feet short of the runway.”

The first dual-seat trainer version, the TB-58A, was delivered to the Air Force in 1960. The TB-58 and the B-58 had identical flight characteristics, including Mach 2 capability. Once the trainers entered service, the number of accidents in operational B-58s decreased dramatically. But pilots weren’t the only crewmen challenged by the aircraft.

The B-58’s fuel system was highly complicated, and required eagle-eye monitoring and control. At Mach 2, the B-58’s center of lift naturally shifted aft, and the shift required a comparable center of gravity shift, which was achieved by transferring fuel to the balance tanks. Ideally, the defensive systems operator relied on his fuel-flow instrument and CG indicator—when everything was working correctly, that is. “Consider what could happen when one or more (and on rare occasions, all) fuel gauges failed,” says Phil Rowe, a defensive systems operator from 1960 to 1965. “How would you know where the fuel was and how much there was? The answers lay in the records and logs the DSO kept…[but] let’s add the complication of fuel transfer valves that might or might not open or close on command. They [failed] with some regularity, just to keep us on our toes. And, oh yes, there was one more nuance to make life interesting. There was a valve between the aft main and the aft balance tank. It was normally kept closed—except when it wasn’t.”

When the airplane was light, and the four General Electric J79 engines were in afterburner, the B-58 could climb at an astonishing 46,000 feet per minute. All that power was put on display during the early 1960s when the B-58 fleet broke a number of speed and range records (with aerial refueling). It won the Thompson Trophy, Bendix Trophy, France’s Blériot Cup, the MacKay Trophy, and the Harmon Trophy. Howard Bialas and his crew were the only bomber crew ever to receive the Thompson Trophy.

Even with its exceptional performance, the B-58 was deployed in only two operational units. One was at Carswell Air Force Base, which was later incorporated into Little Rock Air Force Base in Arkansas, and the other was Indiana’s Bunker Hill Air Force Base (later called Grissom Air Force Base).

With so few aircraft in the fleet and a rather colorful safety record, you’d think that the B-58 was unpopular with SAC flight crews. But that wasn’t the case. “Crews wanted to get in it real bad,” says Ben Baddley. “It was an airplane careers were made from. Not many people can say they went twice the speed of sound.”

Unfortunately, while the B-58 could outrun all of its competition, the world of technology caught up with it. “Speed has a value completely by itself,” says Hallion. “It reduces engagement times and windows of opportunity the enemy has to react to you. Eventually it got to a point where that, in and of itself, wasn’t enough.”

The development of sophisticated surface-to-air missiles (one of which famously brought down Gary Powers’ U-2 in 1960), high-altitude supersonic fighters, and intercontinental ballistic missiles all spelled an end to the B-58’s useful life. “I believe we may have retired it prematurely,” Hallion says. “That airplane had growth potential, and could have been applied to long-range strike and air defense. We took it out of service just at the point when it could have been really useful.”

It wasn’t only the advancement of the enemy’s defenses that led to the demise of the B-58—political infighting and continual budgetary constraints that had plagued the airplane since its inception played their parts also. It just became too expensive. Maintenance crews reported that for every hour the B-58 flew, it took 35 hours of maintenance.

The last B-58 flew in January of 1970. Ben Baddley was the navigator/bombardier on one of the flights ferrying B-58s to their final resting place in the Arizona desert.

“It was a very sad flight for me,” he says. “The B-58 was a fantastic airplane that broke new ground in so many ways. It’s a shame people never really appreciated it for all that it could and did do.”

“Am I proud to be associated with this great aircraft?” asks Bialas. “You bet your life. Would I do it again? In a heartbeat. Was I ever scared? Always.”

Back in the late 1960s, the B-58’s opponents were quick to say that improvements in enemy missiles and fighters made any supersonic bomber useless, but the military minds of the 21st century have a different opinion of the value of an aircraft with paint-blistering speed—especially one that also has stealth technology.

Northrop Grumman, the company that built the B-2 stealth bomber, is working with the U.S. Air Force and NASA on the next-generation Global Strike Mission aircraft. “As the threat gets more sophisticated, we are looking at a combination of high speed and high altitude, combined with advanced high survivability, low-radar-observable technologies,” explains Charles Boccadoro, director for future strike systems at Northrop Grumman. “With supersonic speeds we can reduce travel time between vast distances by a factor of two or three. This means you can strike more targets with fewer aircraft, while increasing the survivability rate of the crew.”

What is this next-generation bomber going to look like? “It takes a lot of what we’ve learned from the B-2 and modifies it for high-speed operation,” Boccadoro says. “At the heart of it will be a new engine design that can maintain high propulsion efficiency for long-duration missions.” One preliminary design shows a slender fuselage blending into a dramatically swept delta wing—a shape that will be familiar to any B-58 fan.