The Convair B-58 Hustler was the first supersonic bomber to be put into operational service, entering service with the USAF in March of 1960. Although the B-58 was destined never to fire a shot or drop a bomb in anger, it provided a key component of the Strategic Air Command's deterrent capability during the 1960s. Despite its high performance and sophisticated equipment, the service of the B-58 was destined to be rather brief, the aircraft serving with the Strategic Air Command for only a decade before being consigned to storage. Part of the reason for this rather short service was the B-58's rather high accident rate, but the major factor was the intercontinental ballistic missile, which entered service at the same time as the B-58.

The origin of the B-58 can be traced back to the period just after the end of the Second World War, at the time of the creation of the independent United States Air Force. In May of 1947, Maj. Gen. Curtis E. LeMay, at that time Deputy Chief of Air Staff for Research and Development, wrote a letter to Lt. Gen. Nathan F. Twining, chief of the Air Materiel Command, to request that work begin on a new jet- powered medium bomber that would be ready for service by the late 1950s. The bomber should have a combat radius of 2500 miles, a cruising speed of at least 500 mph, and a gross weight of 170,000 pounds. It was proposed that the development of such an aircraft would follow the development of the B-52.

General LeMay's proposal led the Air Staff to solicit ideas from the leading US maker of bombing aircraft, the Boeing Airplane Company, as well as to several other manufacturers. At this stage, the project was rather ill-defined. In October of 1947, things had begun to firm up sufficiently that the War Department submitted a requirement for a new medium bomber to the aviation industry. The aircraft was to weigh less than 200,000 pounds, have a 2000 mile radius, and be able to carry a 10,000 pound bombload. It was tentatively assigned the designation XB-55. Boeing submitted the winning proposal, and a Phase I contract was initiated with FY 1948 funds.

However, in the immediate postwar environment, funding for military projects was in short supply and it was decided that the initial design study for the XB-55 would be converted into a paper study to explore new aeronautical technologies. In particular, the Air Force began to explore the potential of delta wing configurations and began to consider the possibility of bomber designs capable of supersonic flight.

Some of this work had actually gotten started before the advent of the XB-55 project, and several companies had launched informal studies. Among the initial approaches to the design of a long-range supersonic bomber was the Generalized Bomber Study (better known as GEBO). GEBO began with the exploration of the the feasibility of a delta-winged aircraft weighing about 150,000 pounds. This began in October 1946 under an Air Force contract given to Convair, since that company had the most experience with delta-winged aircraft. Pre-GEBO studies by Convair of the abortive XF-92 delta-winged interceptor had given that company valuable experience with delta wings.

The delta wing was basically the idea of Dr. Alexander M. Lippisch, a German aeronautical engineer, although NACA had independently explored many of the advantages of delta wings during the war. In postwar years, US government agencies and many US aircraft corporations studied captured German reports on delta-winged aircraft.

By June of 1948, Convair had looked at 10,000 different configurations which explored the effects of different wing areas, aspect ratios, thickness and sweep. In addition, several different types of propulsion systems were considered, both turbojet and turboprop.

At the suggestion of the AMC, the USAF asked Convair to continue its study on the development of future long-range supersonic bombers. This study was formalized in June of 1949 with the granting of a contract for further detailed study

On January 27, 1949, the AMC was directed to cancel the XB-55, since the projected B-47 production rate had reached the point that another subsonic medium bomber would be unnecessary. However, the general requirement for a high-performance medium bomber remained intact.

One of the positive results of the cancellation of the XB-55 project was that it freed up some scarce funds for additional development. Brig. Gen. Donald Putt, Director of the Research and Development Office and Deputy Chief of Staff for Materiel, recommended that the AMC ask the aircraft industry for new and possibly unconventional proposals for intercontinental bombers. A second Generalized Bomber Study (known as GEBO II) was initiated. The design parameters were a a radius of 1200 to 2500 miles with a 10,000 pound bombload, a cruising speed of more than 450 knots, a combat altitude greater that 35,000 feet and a takeoff distance of less than 6000 feet.

In January of 1950, Convair, as part of its work on GEBO II, began to explore a parasite concept. They proposed a fairly small delta-winged aircraft which would be carried part-way to its target underneath a B-36. The aircraft was to carry a two-man crew and would have four turbojet engines. The aircraft would have a composite construction, with a droppable pod containing a bomb bay, a radar scanner, three expendable engines, and the fuel. Launch weight was 100,000 pounds, but landing weight was only 17,900 pounds. Maximum altitude was 48,500 feet. Maximum speed over the target was Mach 1.6, and service ceiling before bomb drop of 52,000 feet. No defensive armament was to be carried, since it was expected that the high performance of the aircraft would make it immune to interception.

The Air Force was highly interested in this parasite concept, but there was some opposition. Many felt that a parasite bomber would be much more expensive than a single aircraft designed to accomplish the same mission, and that the mothership/parasite combination would be quite vulnerable to attack while attached.

In April of 1950, the GEBO II specification was changed to provide for a radius of 3500 to 4500 miles, with speeds as great as Mach 1.5. This changed specification was based on Convair's parasite proposal. By the fall of 1950, Convair had settled on a 100,000-pound aircraft powered by five engines. Three engines would be expendable, with one of the engines being mounted in the centerline pod itself and one expendable engine being mounted in a pod underneath each wing. The centerline pod would also contain fuel and a single nuclear weapon. The main module had a delta wing with two turbojets in partially buried wing nacelles. Once airborne, the B-36 would carry the parasite 2000 miles toward the target, release it and return to base. The parasite would then use its five engines to accerate to a Mach 1.3 cruising speed. Over the target, the speed would increase to Mach 1.5. The parasite would then release the pod containing the nuclear warhead and return home at Mach 1.3. Once safely out of the combat zone, the aircraft would drop its two wing-mounted expendable engines and complete the trip back home at Mach 0.9. The aircraft would have no defensive armament, but it would be equipped with a full suite of electronic countermeasures equipment.

In the meantime, the Boeing Airplane Company, now freed up by the cancellation of the XB-55 project, began to study the possibility of a high-performance medium bomber. Performance objectives included a combat radius of 3000 miles at an altitude of 50,000 feet. The aircraft would be capable of supersonic speed of Mach 1.3 within 200 miles of the target. After looking at several different configurations, the Air Force selected the Boeing Model 484-405B as having the highest potential. The 484-405B was a fairly conventional design, with a low aspect ratio, high-mounted wing with a sweepback of 47 degrees. A bomb bay similar in size to that of the B-47 would be provided. Gross weight was 200,000 pounds. The aircraft was to be powered by four Pratt & Whitney J57-P-5 afterburning turbojet engines. The engines were to be mounted side-by-side, two in the inboard section of each wing. Because the wing was thin in order to make it possible to achieve supersonic performance, the fuel had to be housed entirely within the fuselage. The fuselage housed a pressurized cabin for a crew of three. A remotely-controlled tail turret was to be fitted.

By the end of 1950, the Bombardment Branch of the Air Materiel Command's Aircraft and Guided Missiles Section began to prepare a detailed military specification for both the Boeing and Convair proposals. Based on the AMC proposal, which was in turn based on input from both the Boeing and Convair design studies, requests were made for funds for beginning projects. The supersonic bomber was now officially a part of the Air Force's future plans.

On January 26, 1951, following the completion of the detailed study, Convair proposed that it develop a long range supersonic reconnaissance bomber. The project was given the number MX-1626 by the AMC under contract AF33(038)-21250. The contract called for partial Phase I development (initially without a mockup) of a bomber/ reconnaissance aircraft based on the GEBO II studies. However, the Convair proposal now had only three engines rather than five, with two being permanently mounted in the wing nacelles and one expendable engine being mounted in the droppable pod.

In February, the competing Boeing project was given a development contract by the AMC under the designation MX-1712 and contract AF33(038)-21388. Boeing's contract called for Phase I development of two bomber/reconnaissance aircraft through wind tunnel testing, engineering, and mock-up. Initial flight dates for both designs were tentatively set for late 1954.

The MX-1626 was a two-seat delta-winged aircraft consisting of two main components--a lower droppable bomb-pod and an upper main return component. The return component was a complete aircraft with a tricycle undercarriage to be used only for landing. The aircraft was to be launched from a trapeze which extended downward from its mother craft, but there is a Convair drawing showing the installation of a jettisonable landing gear that permitted takeoffs when the pod was fitted. The return component featured a delta wing with an area of 1200 square feet and a total span of 47 feet. The fuselage was 82 feet long. At the rear of the fuselage was a triangular-shaped vertical tail. A pair of nonafterburning General Electric J53-GE-X25 turbojet engines were mounted in midwing pods. The long pointed pod was integrated into the bottom of the aircraft, and featured three large fins separated by 120 degrees. The free-falling bomb pod was to be roll-stabilized by the control surfaces in the two upper tails. A third J53 engine was to be mounted inside the pod and would be expended when the pod itself was dropped. A maximum speed over target of Mach 1.7 was anticipated, and a maximum total mission radius (carrier plus parasite) of 4000 nautical miles was anticipated.

Convair's parasite proposal turned out to be very short-lived. The parasite idea had arisen at a time when cost factors were particularly important, and it was thought that such an approach would provide a cost-effective answer to the problem of long-range strategic bombing. However, it soon became apparent that the two aircraft would require complex navigational equipment so that they could find each other on the return part of the mission. While joined, the two aircraft would be especially vulnerable to attack. In addition, the two-aircraft attack system would be much more expensive to build and maintain than a single bomber. Consequently, in December of 1951 the MX-1626 design was drastically revised. The parasite idea was abandoned in favor of a single aircraft that would be capable of being refuelled in midair. The third expendable engine in the bomb pod was eliminated, and afterburners were added to the aircraft's remaining two engines. A landing gear capable of supporting both landings and takeoffs would have to be provided. Gross weight rose to about 126,000 pounds and the number of crew members rose to three (pilot, navigator-bombardier, and defense systems operator).

On February 1, 1952, the USAF issued General Operational Requirement SAB-51, where SAB stood for Supersonic Aircraft Bomber. It called for a multi-mission strategic reconnaissance bomber capable of carrying 10,000 pounds of bombs. It had to be capable of operating in all weather conditions, and had to be able to achieve a combat radius of 5000 miles with a single outbound inflight refuelling. It had to be capable of supersonic performance at altitudes of 50,000 feet or more and of high subsonic performance at lower altitudes. It was considered important that the aircraft be fairly small, since this would reduce the radar reflectivity and make the aircraft harder to detect. The Air Force wanted production to begin within five years.

On February 26, 1952, the SAB-51 GOR was revised in a document which came to be known as Directive Number 34. It was conceded that it was unrealistic to expect the rapid development of a high-altitude, long- range supersonic bomber that could also be suitable for low-altitude high speed missions. Consequantly, the low-altitude performance requirement was dropped. Following discussions with the Air Council and representatives of the ARDC, SAC, the Rand Corporation, and the Scientific Advisory Board, the Air Force endorsed this recommendation, and the revised SAB became formalized on September 1, 1952 as SAB-52-1. However, the Air Force still wanted the aircraft by 1957.

At the end of February 1952, General J. W. Sessums, ARDC Deputy for Development recommended that it would be better to forego the traditional industry-wide competition that would ordinarily be held for the supersonic bomber project. Time and money would be saved if contractors could be selected on the basis of the proposals already submitted. Although the AMC felt that the Boeing and Convair proposals offered the best hope for a supersonic bomber, the AMC had requested informal proposals from other manufacturers, including Douglas, Lockheed, Martin, and North American. However, only two of the last four companies actually submitted proposals, and these were not very interesting. Shortly thereafter, the Wright Air Development Center endorsed this strategy and called for a competition between Boeing and Convair, the only two companies to have submitted proposals that were of any significant interest. The Air Force was now committed to the advanced bomber project, and placed heavy emphasis on the MX-1626 and MX-1712 programs. It requested that two parallel Phase 1 projects be initiated, thus engaging Boeing and Convair in an official competition. It was anticipated that contracts would be issued to both competitors in the fall of 1952 for detailed designs and mockups, followed by the selection of a winning design in February or March of 1953. The emphasis would continue to be on minimum size and maximum altitude and speed performance.

The financing of the Phase I development of two parallel projects was extremely difficult to support, especially during a period of financial austerity. The Boeing MX-1712 program had benefited somewhat from the XB-55 cancellation, which freed up some Boeing developmental funding for the new project, but Convair's MX-1626 was experiencing a severe funding problem. In late February, the MX-1626 program was almost cancelled due to the lack of funds, and the project remained in some danger until May 15, when enough additional funds were obtained to keep the project going.

In June of 1952, Convair proposed that they move the engines to nacelles placed underneath the wing. The engines were to be either two J75-P-1s, two J67-W-1s, four J57-P-7s, four J73s, or two J77s.

Directive 34 had also dictated that the project use the weapons system concept, in which the equipment, weapons, electronics, and components of the aircraft would be developed as an integrated whole to ensure that each component would be compatible with the others. By mid-1952, both Boeing and Convair had made considerable progress in bringing their projects into compliance with the weapons system philosophy. In the process of making their designs conform with the requirements of Directive 34, Convair's MX-1626 was now known as MX-1964 and Boeing's MX-1712 was now called MX-1965. The USAF designations B-58 and B-59 were tentatively assigned to the two competing projects, even though no production orders were yet forthcoming.

In the summer of 1952, the Wright Air Development Center concluded that a less costly alternative would be to select just one of the two competitors even before the design and mockup stage was reached. The small bomber concept was endorsed by the Air Force Council and by General Hoyt S. Vandenberg, who was Chief of Staff of the Air Force. However, General Curtis LeMay, head of the Strategic Air Command, generally favored larger bombers with longer ranges. SAC felt that high performance alone would not necessarily assure mission success, and that the small supersonic bomber's lack of range would prevent it from operating without midair refueling from most forward bases. Despite SAC's objections, the Wright Air Development Center recommended that the Boeing/Convair competition be stopped. Even though the Air Force thought that Convair's estimates of the MX-1964's supersonic drag and gross weight were overly optimistic, the Air Force felt that the Convair design was superior to the Boeing proposal, since they felt that the Boeing design would offer insufficient supersonic capabilities, and on November 18, 1952, General Vandenberg formally announced that Convair was the winner of the contest.

On December 2, 1952, it was announced that the designation of the new bomber would be B-58. The Deputy Chief of Staff for Development endorced a production schedule based on the four-year procurement of 244 B/RB-58s. The first 30 would be used for testing, and they would be reworked on the production line as problems appeared and were solved. This plan was based on the "Cook-Cragie" philosophy, in which the prototype phase was skipped. This plan, named for General Laurence C. Cragie, Deputy Chief of Staff for Development, and Orval R. Cook, Deputy Chief of Staff for Materiel, was rather risky and was really applicable only when there is a fairly high degree of certainty that the aircraft is actually going to go into production. The F-102 interceptor had been designed according to this principle.

On February 12, 1953, the Air Force gave Convair the go-ahead to begin detailed Phase I work on the XB-58 and XRB-58. At this point, only the basic concept had been approved, not any detailed design. On March 20, the Air Force indicated its acceptance of a firm configuration with a 60-degree delta wing with the trailing edge swept forward by ten degrees. A small amount of leading edge camber was provided to reduce drag due to lift. The aircraft was to be powered by four General Electric J79 turbojet engines, with the two inboard units mounted on underwing pylons and the two outboard engines mounted on the wing upper surface.

Even though Convair had been selected over Boeing, many revision of the MX-1964 design were to follow. At the same time, development problems with Convair's F-102 interceptor confirmed the Air Force's suspicion that the initial estimates of the aerodynamic drag of a delta winged aircraft had been overly optimistic. NACA engineer Richard T. Whitcomb's ideas on the Area Rule had been verified in December of 1952, which suggested that the cure for excessive transonic drag was to equalize the cross-sectional area at all points along the fuselage, thus producing a narrow ("coke bottle") fuselage in the region of the wing. The crew was to be three--a pilot, a navigator/bombardier, and a defensive system operator. The defense was to be one 30-mm gun mounted in a remotely-controlled tail position.

The first development engineering inspection took place on August 17/18, 1953. At this stage, the B-58 mockup was known as Configuration II. The requirements matched fairly closely with the specifications issued by Convair in August of 1952 as well as with the USAF demands issued in the September 1952 GOR. At this stage in the design, the fuselage of the B-58 still consisted of an upper component and a lower pod that were integral with each other rather than being separated by a pylon. The return component had a flat fuselage undersurface once the disposable pod component had been jettisoned. In addition, nose gear requirements were complicated by the fact that both the pod and the return component required a nose gear. In the development engineering inspection of August of 1953, it became obvious that this pod would have to be completely redesigned. In October of 1953, the Air Force authorized Convair to shorten the pod to a length of 30 feet and to separate it from the fuselage by a pylon. In addition, the search radar was taken out of the pod and put in the nose of the upper compartment. The droppable nose gear was eliminated, and external fuel tanks were added to compensate for the fuel lost due to the shorter pod, and the postions of the navigator/bombardier and defensive systems operator were reversed.

The revised B-58 design was known as Configuration III. External fuel tanks were added to the wing tips in the interest of longer range. Configuration III also omitted the jump seat which had been requested in the original military characteristics. However, there were still problems being uncovered by the wind tunnel testing at the Wright Air Development and at the NACA. In 1953, the contractor and the Air Force had decided to mount the four turbojet engines inside two split-cell strut-mounted underwing nacelles, reminiscent of the inner two-engine pod of the B-47 Stratojet. It was thought that this configuration would save weight, ease engine maintenance, and facilitate retrofit of J57 engines with new J79s. However, wind tunnel testing indicated that the split-cell nacelles induced extra drag on the pod-carrying B-58. These problems caused a postponement of the Configuration III mockup from May to September 1954.

It was planned that the first 30 aircraft would be used for tests and evaluation. The first 18 of these would be powered by Pratt & Whitney J57 engines, while the remainder would be powered by four General Electric J79-GE-1 turbojets (known in the prototype form as the J73-X24A).

By August of 1954, what was to prove to be the final B-58 configuration was chosen. The engines were now mounted inside four individual underwing pylons, and all fuel was contained internally and in the podded lower component. The fuselage was aligned to the modified transonic area rule for supersonic speeds. The external wing tanks were eliminated, and the tail area was increased to 160 square feet.

In the meantime, the Strategic Air Command was still unhappy with the B-58. A mid-1954 staff study had actually excluded the B-58 from its projected 51-wing bomber force of 1958-1965. There were fears from even the B-58's most fervent supporters that even the latest configuration might not meet all the requirements of the military specification, but they still believed that the aircraft should be built even if the Air Force could not actually use it as originally intended. By this time, almost 200 million dollars had been spent. There was some thought to reorienting the program to a research and development effort, and even some thought to cancelling the program altogether. In June of 1955, a decision was made to restrict the program to just 13 aircraft. However, on August 22, 1955, this decision was reversed again and the B-58 was once again authorized for production. A wing of B-58s would be ready for service by mid 1960. However, there was at this time no mention of which branch of the Air Force that this wing would actually belong to.

In December of 1955 a definitive contract was issued to Convair for 13 aircraft and 31 pods. A second Letter Contract, AF33(600)-32841, issued on May 25, 1956, provided additional money to maintain B-58 production at a minimum sustaining rate through October of 1956. In the fall of 1956, the Air Force would decide if it should buy more aircraft.

A total of 86 production B-58As were built.
Fuselage

The fuselage of the B-58 was of semi-monocoque construction and had the standard bulkhead, former, and longeron construction that was typical of most other military aircraft of that era. There were 19 bulkheads. The area between bulkheads 1 and 5 carried the crew compartments. The volume aft of bulkhead 5 and all the way to bulkhead 19 was devoted exclusively to fuel except for the navigation system stable table area between bulkheads 8 and 9. The portion of the fuselage aft of bulkhead 19 contained the deceleration parachute, the tail armament, and electronic equipment.

Crew

The crew of the B-58 consisted of a pilot, a navigator/bombardier, and a defensive systems operator (DSO), all seated in tandem in three separate compartments. The pilot sat in front, the navigator/bombardier in the middle, and the DSO in the rear. A crawlway between the pilot's station and the second crew station on the right side of the fuselage could only be used for maintainence of electronic equipment, but a crawlway between the second and third crew stations could be used for passage during flight. The navigator/bombardier's panel was equipped with bomb and pod dropping instrumentation, bombing system indicators and monotors, plus the navigation equipment. The DSO's panel contained passive and active defense system monitors.

Structurally, the three crew compartments comprised a single pressurized cabin, but structal bulkheads and equipment created a compartmentalization effect. Each compartment had a separate canopy hinged at the rear for entry and exit. The compartmentilization prevented direct vision or physical contact between crewmembers during flight. The pilot had a windshield with six adjacent panels, plus one panel on each side of the canopy. This afforded excellent outside vision, and the pilot could see parts of the exterior of the aircraft as well as the engine nacelle inlets. The navigator/bombardier and the DSO only had small side windows.

The crew members were seated on individual ejector seats which were catapulted out of the top of the aircraft by a rocket engine. Problems with the originally-fitted SAC-type ejector seats when they were called upon to be used for emergency exit in the supersonic regime led to the development of an encapsulated ejection system developed by Stanley Aviation of Denver, Colorado. The unit protected the pilot against supersonic wind blasts, supplied oxygen and pressurization during an ejection at high altitude, absorbed landing impact and had survival equipment installed. Each capsule was an independently operating unit which required no outside power source. The second and third crew stations were identical and were both ejected on vertical rails. The pilot's capsule was similar, but included a flight control stick and was ejected on slightly leftward-canted rails. A three-piece telescoping clamshell door was pivoted on each side of the seat. It was stowed above the crew member's head during normal flight. It was actuated by raising the ejection handle, causing the doors to rotate downward to form a pressure-tight capsule. The doors could be closed in about a quarter second after actuation. Emergency oxygen and pressure were automatically actuated by door closure. After the doors were closed, each crew member manually ejected his own capsule by squeezing the trigger on the ejection handle, which jettisoned the canopy and fired the rocket catapult initiator. During high speed ejection, capsule stability was provided by the stablization frame and by a stabilization parachute. The recovery parachute was automatically deployed at a preset altitude. Landing impact was cushioned by crushable cylinders and stablization fins. For water landings, flotation bags were provided. During an emergency, the aircraft could still be flown while the pilot was encapsulated, and a small window in the capsule clamshell door provided a view of the instrument panel, while the pilot's control stick permitted controlled flight.

Wings

The wings of the B-58 were of fully cantilever, modified delta type with cambered leading edges and outboard tips. They incorporated multispar construction with a sandwich panel covering that was secured with titanium screws. The leading edges were of sandwich-type skin construction preformed to shape without any internal bracing.

The internal structure of the wing consisted of multispar construction with bulkheads at the points of major load. The two inboard bulkheads located in the wheel well area were large channels that were flanged away from the wheel well to allow maximum clearance for the main landing gear retraction. The spars were made so that contact with the wing skin was on a curved surface to allow the wing skin to more closely approach the contour of the desired airfoil. The wing sandwich panel was made up of aluminum sheet skins, adhesives, fiberglass and aluminum honeycomb core, and a machined aluminum grid.

The entire wing served as an integral fuel tank which was sealed from the outside during construction. Free-flow openings in other spars and bulkhead allowed fuel to flow between sections. Check valves prevented fuel flow between left and right wing sections when one wing was high. The wing panel figerglas cores served to insulate the fuel in the wings from the external heat.

Rudder

The vertical tail was a sweptback, truncated structure with spars and ribs providing the internal framework. The fin cap was fabricated of laminated fiberglas. The rudder had a full-depth aluminum core with an aluminum alloy skin bonded to it. It was hinged at 11 points along the front spar. The elevons were made of steel sandwich panels with a brazing alloy used as a bonding agent.

Flight Control System

The control surfaces consisted of a rudder and two elevons. The pre-production B-58s also had two resolution surfaces, located inboard of the elevons. These were used to mask out the effects of mechanical backlash in the longitudinal control system and were completely automatic. However, they were found to be redundant to the primary trim system and were eventually eliminated from all production aircraft, and were removed from existing pre-production aircraft as well.

The flight control system incorporated three-axis damping, constant stick forces throughout the entire speed range, and continuous g protection, making it virtually impossible to manually overstress the airframe when in automatic flight mode. An artificial feel system was installed, and altitude and Mach number control was providded for station keeping, approach control, landing, and flareout.

The flight control system included an automatic trim system which had three modes of operation: takeoff and landing, manual, and automatic. In the takeoff and landing mode, the trim system was locked at 3 degrees up elevator. In the automatic mode, the automatic trim system provided the elevon deflection required for 1-g flight. The auto trim system was closely associated with the ratio changer or g-protection system.

There was an aileron-rudder interconnect system that served to cancel out out the yawing that normally resulted from aileron deflection. Artifical pitch, roll, and yaw damping were supplied to minimize variations in flight characteristics and to provide satisfactory damping. There was also a "wing heavy" control system which sensed lateral accelerations and provided corrective rudder through the rudder damper servo to prevent lateral fuel shift and subsequent wing heaviness.

The Eclipse Pioneer autopilot system provided a constant Mach number by automatic control of the elevators. The aircraft was maintained at the desired altitude and Mach number by automatically controlling the elevators and throttles. The heading was maintained by automatically steering the aircraft along a constant track or a computer ground track.

Landing Gear

The main landing gear assemblies consisted of 8-wheel bogies, four wheels on each axle. Between each pair of tires there was a steel non-frangible wheel which was installed after mid-1961 in response to the continual problems that the B-58 had encountered with tire failure during landing and takeoff. The main gear was fitted with a set of multiple disk-type anti-skid brakes The main gear bogies were attached to large legs which were in turn connected to the underwing attachment points by large u-shaped connecting units. The main gear assemblies retracted into faired wing wells located inboard of the inboard engine pylons and nacelles. In order to provide sufficent space for the retracted wheel units within the thin wing, the wing wells projected significantly above the wing upper surface, being encapsulated under a wedge-shaped aerodynamic enclosure. The gear retraction mechanism was fairly complex, with the main unit retracting backwards into the wing recesses. During retraction, the main leg folded at the point where it joined the u-shaped connector in order that the whole unit could fit inside the bay. In spite of the complex retraction scheme, main landing gear retraction or extension failures were fairly rare. However, strut, bogie, and axle assemblies did occassionally break, resulting in damage to the aircraft and at least one complete writeoff.

The nose landing gear consisted of a pair of tires attached to a rather complex strut that retracted into a a well covered by a pair of doors. The complexity of the strut was in part due to the fact that the gear had to clear the nose of the ventral pod during extension or retraction. The strut was hinged so that the main strut rotated up and back into the well while providing clearance for the pod. The nose gear was fully steerable from the front cockpit.

The full sequence of landing gear retraction and extension took about 10 seconds.

The deceleration parachute system was housed underneath the rear fuselage just in front of the tailgun installation. It was a 28-foot ring slot parachute assembly housed inside a stowage compartment enclosed by dual clamshell doors. The pilot could jettison the parachute at his discretion.

Engines

The B-58 was powered by four General Electric J79 turbojets, housed in separate pods. The two inner pods were suspended underneath the forward part of the delta wing underneath pylons, whereas the two outer pods were attached directly to the wing undersurface.

The YJ79 was an axial-flow turbojet with a 17-stage compressor and a three-stage turbine. It was equipped with a variable exhaust nozzle, and air entering the compressor section was automatically controlled by variable positioning inlet guide vanes.

The variable exhaust nozzle system automatically controlled the exhaust area to provide for optimum thrust and specific fuel consumption under varying engine operating conditions. It also protected the engine from overheating. The system consisted of primary and secondary nozzle flaps, plus associated control units and actuators. Each primary nozzle control was mechanically interconnected with the engine throttle and synchronized so that throttle movement would automatically result in proper primary engine nozzle setting. The secondary nozzles were used to provide maximum thrust and reduced drag during cruise and military operating ranges. These were opened during idle and afterburner operation, and were closed for operations in the cruise and military ranges.

Each engine nacelle was equipped with a variable-position intake spike which could be moved forward or aft in the inlet to maintain an efficient airflow to the engine throughout the speed range of the aircraft. During normal operation, control of the spike was completely automatic. The spike remained in the aft position until an airspeed of Mach 1.42 was reached. At that speed, a switch in the air data computer closed and activated the system. The transducer then moved the spike forward to the appropriate location for the particular airspeed.

Engine cooling was provided by using two scoops located in the air inlet of each nacelle. Ram air was passed via these scoops through a series of bypass flaps into the hydraulic oil cooler, then aft between the engine and the nacelle walls to be expelled into the engine exhaust gases.

Fuel System

The fuel system of the B-58 was the most complex and sophisticated yet installed in an operational aircrft. The JP-4 fuel was stored in four main tanks, termed forward, aft, reservoir, and balance units. Two more fuel tanks were installed in the underfuselage pod (a total of 4172 US gallons in the MB or LA pod and 3885 US gallons in the TCP pod). The fuel system could operate with or without the pod being installed. The forward portion of both wings, as well as the fuselage volume between bulkheads 5 and 6 comprised the forward tank, which could accommodate up to 3202 US gallons of fuel. The aft portion of both wings and the fuselage volume between bulkheads 9 and 12 comprised the aft tank, which was capable of carrying up to 5893 US gallons of fuel. The fuselage section between bulkheads 6 and 8 comprised the 610-gallon reservoir tank, and the fuselage section between bulkheads 12 and 19 comprised the 1219-gallon balance tank. The reservoir tank acted as an accumulator tank by utilizing an autotransfer system which maintained a specified tank level until the other tank supplies had been depleted. The balance tank was not used for direct engine supply, but fuel could be transferred from the balance tank to the forward tank when needed. The center of gravity could be maintained either automatically or manually by transferring fuel between the forward, aft, and balance tanks.

The B-58 was equipped with a mid-air refueling system, mounted in the upper portion of the nose radome some 45 inches ahead of the pilot's windshield. It consisted of a receptacle for a KC-135A flying boom probe. When not in use, the system was covered by a door which was normally flush with the contour of the radome. When the slipway door was opened, it formed a guide for the entry of the flying boom.

The B-58 was equipped with an emergency fuel dump system. The fuel could be dumped via a a probe which extended two feet outward from the left side of the balance tank just aft of the wing trailing edge.

Defensive Systems

The defensive armament of the B-58 consisted of a General Electric T-171E-3 six-barrel 20-mm rotary cannon with a maximum firing rate of 4000 rounds per minute. The gun was mounted inside the extreme tail, on the axis of an articulated cone which consisted of tapered, concentric aluminum rings which were spring-loaded against each other. The tailgun assembly was aerodynamically faired to conform to the rest of the aircraft.

The Emerson MD-7 radar for the tail gun was located in a bullet fairing above the tail cone. The MD-7 radar was a Ku band unit. Data from the radar was fed to a computer mounted directly behind the gun and was then relayed electromechanically to the gun itself. Mach number and relative air density information were automatically supplied to the fire control system by the air data computer. The gun was aimed remotely by the fire control system in the tail, but there was a radar (automatic) fire control panel and a manual fire control panel located at the DSO's station, and the gun was actually fired by a button located there.

A total of 1200 rounds could be carried. Ammunition was drawn from a box in the fuselage just forward of the turret. The firing zone was any target within a 30-degree cone. During firing, spent ammunition shells were ejected through a ventral door.

The defensive electronic countermeasures system provided an early warning of the presence of enemy radar systems and could be used to deceive, confuse, or jam them. The system consisted of AN/ALR-12 radar warning equipment and an AL/ALQ-16 radar track breaking equipment. An AN/ALE-16 chaff dispensing system was installed in each upper main gear fairing, with chaff being ejected through mechanically-acutated slots in the tops of each wing fairing. The AN/ALQ-16 radar track braker was a repeater type jammer that generated deceptive radar jamming signals as a function of RF energy received from enemy tracking radars. When tracking radar signals were received, the track breaker generated and transmitted deceptive angle and range information, causing the tracking radar servo system to generate false antenna positioning information which in turn caused the tracking radar to compute false range information.

Electronic Systems

The aircraft was equipped with a Raytheon Ku band (16-17 GHz) search radar, with the antenna mounted in the extreme nose. There was also a daytime-nightime Lollsman Instruments KS-39 astro-tracker which automatically tracked a preset celestial body via a photocell mounted in a telescope and was so designed that it held the observed body in the center of the field of view.

The navigation/bombing system was a Sperry AN/ASQ-42 system. This system consisted of six major subsystems.

An aft-fuselage mounted AN/APN-113 Doppler radar which determined the ground velocity of the aircraft and also calculated airspeed and wind.

The heading subsystem including the astrotracker and the remote compass transmitter which determined the true heading of the aircraft.

A navigation subsystem which continuously computed the latitude and longitude of the aircraft.

A sighting subsystem which consisted of the nose-mounted search radar and radio altimeter which established the position of the aircraft relative to a given point on the earth.

An indicator subsystem which contained controls used by the navigator and pilot in the operation of the primary navigation system. In addition, it generated the pod release signal during the bombing run.

A malfunction system used to detect failures in the primary navigation system while also providing for alternative methods for completing the mission.

The primary navigation systems were provided by Bendix and Motorola. It was basically a Doppler inertial system using the astro tracker for a primary heading reference. While enroute, the position and course were continually computed by a precise dead reckoning system. Periodic search radar sightings were used to check the accuracy of the dead reckoning, and corrections were made as necessary.

Midway through its operational career, the B-58 was fitted with a voice warning system with a pre-recorded female voice that would inform the crew when an emergency was taking place. Every major event from an engine fire to a hydraulic failure was included in the set of events, and a total of 20 emergencies could be programmed into the system from 50 inputs.

The Magnavox communication system provided a means of crew intercommunication, plus normal and emergency air-to-air and air-to-ground communication. An AN/APX-47 IFF system was installed. Also included were AN/ARN-69 TACAN, AN/ARN-50 VHF navigation equipment, as well as AN/APN-136 and AN/APN-135 beacons.

Offensive Weapons

The primary offensive armament of the B-58 Hustler was caqrried in an underfuselage centerline pod, a pod which was almost as large as the fuselage itself.

The MB-1C pod was the standard free-falling pod unit that was carried underneath the B-58 fuselage on the centerline. It was basically a finned aerodynamic shell that carried a pair of fuel tanks plus a variable-yield thermonuclear bomb. The pod was 75 feet long with a diameter of about 5 feet. Empty weight was 2500 pounds without the fuel and the warhead being installed, but when fully loaded with fuel and carrying the standard W39Y1-1 warhead it weighed 36,087 pounds. The pod was attached to the aircraft by three hooks. The pod had an equipment bay, a forward fuel tank, a bay for the thermonuclear weapon, an aft fuel tank, a tail cone and fins, plus an attachment pylon. The four fins were mounted at 45 degrees from the horizontal centerline and were slightly offset to give the pod a slow spin during free-fall. The warhead was fused by a set of barometric switches, set to trigger the weapon when the preset pressure was reached. Fuel and fuel pressurization disconnects were released and were closed instantly when the pod was released.

AN/ASH-15 Indirect Bomb Damage Assessment equipment was installed inside the aircraft fuselage to give continuous pod position data to the aircraft after pod release. This data was saved on an inflight recorder inside the aircraft. At the time of warhead detonation, a photocell in the aircraft recorded the light intensity of the burst, and from the data recorded the yield, pressure, the altitude of the burst, the pod-to aircraft range, and the azimuth from the aircraft could be determined.

Some MB-1C pods were modified to incorporate a Fairchild KA-56 camera in a forward compartment. When so modified, the pod was redesignated LA-1. The system consisted of the camera and magazine, a scanner and converter, a control panel, and associated air conditioning and electrical systems. The pod camera control panel was located at the navigator's position and repleced the weapons monitor and release panel when the photo recon pod was installed.

The MB-1C pod had a relatively short service life because there were persistent problems with fuel leakage into the weapon bay. Several years of fighting with this problem lead to the introduction of the two-component pod.

The Two-Component Pod (or TCP) had the same overall profile as the older MB-1 and used the same attachment points. However, it was built in two separate sections. The TCP was actually two pods, an upper BLU 2/B-1 bomb pod and a lower BLU 2/B-2 fuel pod. The warhead unit could be retained while discarding the lower fuel pod.

The 35-foot long upper component contained two fuel tanks, separated by a warhead cavity. Maximum diameter of the upper component was 3.5 feet. A pylon and three fins were fitted. Two of the fins were mounted on the sides of the pod at 30 degrees above the horizontal, and the third (lower) fin was retracted within the upper pod while the lower pod was still attached. This lower fin deployed automatically upon lower pod release. The gross weight of the upper component when equipped with maximum fuel and a Mk.53 nuclear warhead was 11,970 pounds.

The lower component was also divided into two tanks, separated by a common bulkhead. It was supported underneath the upper pod by one forward and one aft releaser. There were no fins, but a pivot strut was mounted on the aft end of the pod to facilitate proper separation from the aircraft during release. The large lower pod was expendable and was released during flight when all the fuel in both the upper and lower components was consumed. The bomb pod remained with the aircraft for release during the delivery run. The empty weight was 1900 pounds, whereas the gross weight was 26,000 pounds.

Both the MB-1 and the TCP remained in the active inventory until the end of the B-58 program. Because of its several advantages, the TCP was the preferred pod, but the MB-1 pod accommodated a much larger warhead.

The MA-1C pod was a proposed rocket-propelled version of the MB-1 free- fall pod, designed to give the B-58 a stand-off capability. The pod was to be powered by a Bell Aerospace LR81-BA-1 rocket engine, fueled by a combination of JP-4 and red fuming nitric acid. The maximum range was expected to be 160 miles. During the flight to target, a maximum altitude of 108,000 feet and a maximum speed of Mach 4 was to be obtained. A Sperry guidance system was to control the pod during its flight to the target. However, the MA-1C pod was cancelled before it could be deployed.

The MC-1 was a proposed dedicated photo-reconnaissance pod. In 1953, the Fairchild Camera and Instrument Company was given a contract to develop a dedicated photo-reconnaissance pod for the B-58. The system could be installed within the standard MB-1C pod, and the only actual airframe modification would be the replacement of the package and bomb system equipment in the second crew station by photo navigation equipment. The MC-1 was to have a multi-camera system consisting of three 36-inch format cameras installed in a stabilized mount, a tri-camera system consisting of 3 6-inch cameras, one 3-inch forward oblique camera, a camera control system, a nose-mounted television view finder, a fan of five 3-inch cameras, a Melpar recording system, a Sperry navigation system, and a Raytheon search radar scope camera. However, in early July of 1955, the reconnaissance pod was cancelled due to funding limitations. The program was reinstated in September of 1955, when funding was again made available. However, the program was cancelled for good in early 1958, after only one pod had been completed. This pod was never actually flown under a B-58, although 55-0671 had been scheduled as the testbed aircraft.

The MD-1 was a proposed electronic reconnaissance pod which used many of the shell components of the standard MB-1 free-fall pod. It was equipped with a wide range of electronic sensors to analyze and record all enemy radar signals that reached the aircraft. Only one example was actually completed, and it was never actually flight tested.

Midway throughout its career, the B-58 was reconfigured to carry four Mk.43 thermonuclear weapons on external pylons underneath the wings between the fuselage and the main landing gear bays. Two weapons were carried on either side of the fuselage in tandem. The Mk.43 weapon was about 12 feet long, 1.5 feet in diameter, weighed about a ton, and had a variable yield of up to 1 megaton.

Specification of Convair B-58A Hustler

Powerplants: Four General Electric J79-GE-5A/5B axial flow turbojets, each rated at 9700 lb.s.t. normal power, 10,300 lb.s.t. military power, and 15,600 lb.s.t. maximum afterburner. Performance: Maximum speed: Mach 2.2 at 40,000 feet, Mach 0.91 at sea level. Cruising speed 521 knots. Takeoff ground roll 7850 feet at 160,000 pounds. Landing ground roll 2615 feet at 63,100 pounds. Maximum initial climb rate 38,650 feet per minute at sea level. An altitude of 30,000 feet could be attained in 11.2 minutes. Normal cruise altitude 38,450 feet. Target area altitude was 55,900 feet. Combat ceiling 63,400 feet. Maximum ferry range 4100 nautical miles. Weights: 55,650 pounds empty (without pod). Maximum gross weight 176,890 pounds (in flight). 63,100 pounds landing weight. Dimensions: Wingspan 56 feet 9.9 inches, length 96 feet 9.4 inches, height 29 feet 11 inches, wing area 1364.69 square feet. Armament: One General Electric T-171E-3 remotely-contolled cannon in tail with 1200 rounds. Offensive weapons consisted of one MB-1C pod containing a W39Y1-1 variable-yield thermonuclear warhead, or a a Two-Component Pod with a Mk.53 thermonuclear warhead. In addition, four Mk.43 thermonuclear weapons could be carried on external pylons underneath the wings between the fuselage and the main landing gear bays.

Serial Numbers of Convair B-58 Hustler:

55-0660/0672 Convair YB-58A-1-CF Hustler
All later redesignated B-58A.
58-1007/1023 Convair Y/RB-58A-10-CF Hustler
58-1024 Cancelled contract for RB-58A Hustler
59-2428/2463 Convair B-58A-10-CF Hustler
60-1109 Convair B-58B Hustler - cancelled contract
60-1110/1129 Convair B-58A-15-CF Hustler
60-1130/1148 cancelled contract for Convair RB-58A Hustler
61-2051/2080 Convair B-58A-20-CF Hustler
Convair TB-58A Hustler
The single-pilot configuration of the B-58, along with its high performance and its unusual flight characteristics (in particular, the nose-high landing and takeoff attitudes characteristic of a delta-winged aircraft) led to a requirement for a training version of the Hustler. Instead of building entirely new airframes for this project, it was decided to convert airframes from the original test batch of 30 aircraft to trainer configuration. On February 25, 1959, the Air Force first authorized the conversion of four early test B-58As to the training configuration under the designation TB-58A. New airframes were not The TB-58A program was formally approved on September 15, 1959.

In the TB-58A, the pilot trainee sat in the forward station. The second crew station was modified to accommodate an instructor pilot who was afforded with the necessary flight controls for inflight instruction and safety. This included a set of conventional flight controls which were mechanically linked to those in the front cockpit. The instructor pilot's seat was slightly offset to starboard by ten degrees to permit better forward vision. The third station was usually occupied by a pilot requiring proficiency training.

Externally, the TB-58A differed from the B-58A in having additional transparencies in the second cockpit area (to the side and overhead) to give the instructor pilot sitting in the second crew station with a better view. The instructor's compartment was completely sealed off from that of the student in the front cockpit, although a split transparency permitted forward view. During flight, the occupants of the second and third stations could change places via the crawlspace. All of the tactical equipment was removed--there was no autopilot, no primary navagation system, no bombing system, no defensive electronic countermeasures system, and no active defense system.

The first TB-58A conversion was carried out on 55-670. It was completed in February of 1960. It carried out its first test flight on May 10, 1959. The first TB-58A was delivered to the Air Force in August of 1960. A total of eight TB-58As were eventually created.
Testbed for YF-12A Weapons System
Another somewhat less well-known role for the Hustler was that of a testbed for the weapons and fire control system of the Lockheed YF-12A Mach 3 interceptor.

The missile and fire control system for the proposed YF-12A was to be the Hughes Aircraft Company AN/ASG-18 fire control system and associated GAR-9 (AIM-47A) air-to-air missile that had originally been developed for the abortive F-108 Rapier program. Since the weapons system was going to be ready for test before the YF-12A aircraft was, the USAF decided that they could speed up the program by fitting the weapons system into a special testbed aircraft that would do some of the earlier evaluation of the system until the YF-12A could be ready.

On October 17, 1958, Convair received a contract from Hughes and the USAF to manufacture two special pods for GAR-9 missile launch tests and to modify one B-58 for AN/ASG-18 testbed work. B-58A serial number 55-665 was selected for the modifications.

In order to fit the rather large AN/ASG-18 fire control system into the B-58A, nearly seven feet had to be added to the overall length of the aircraft. The AN/ASG-18 radar system had one of the largest articulated antennae ever mounted on an aircraft up to that time. The AN/ASG-18 system also had a significant infrared capability, and an infrared sensor dome was mounted on each side of the forward fuselage ahead of the cockpit. Internal changes had to be made in the second crew station and elsewhere to accommodate the associated instrumentation and control equipment.

A special ventral pod had to be developed to carry and launch the GAR-9 missile. The new type of pod carried no fuel, but had a large internal bay for a single GAR-9 missile with associated cooling system, telemetry equipment, and tracking flares. Two pods were built.

The flight testing of the radar began in early 1960, but the first GAR-9 launch did not take place until May 25, 1962. By late 1963, the YF-12A flight test program was sufficiently well advanced that it was concluded that it was now possible for future GAR-9 missile launches to take place from the YF-12A itself. The last B-58 GAR-9 launches took place in February of 1964.

After the completion of the ASG-18/GAR-9 test program, the special modifications were removed from 55-0665. However the long nose was retained. 55-0665 was eventually placed out in the open on the photo test range at Edwards AFB
NB-58A Testbed for General Electric J93
Another little-known role for the B-58A was that of flying testbed for the General Electric J93 turbojet

The General Electric J93 turbojet engine was designed as the powerplant for both the North American XB-70A Valkyrie bomber and the North American XF-108 Rapier interceptor. The J93 was a single-shaft axial-flow turbojet with a variable-stator compressor and a fully-variable convergent/divergent exhaust nozzle. The maximum sea-level thrust was 31,500 pounds.

The J93 engine was ready before either the XB-70A or the XF-108 were, so the Air Force concluded that the engine should be initially flight tested in an existing aircraft. B-58A serial number 55-662 was selected for the project, and on July 1, 1959, Convair began the modification of the aircraft so that it could accept the installation of a J93 engine in a specially-modified underfuselage pod. Following the completion of the Convair modifications, the aircraft was delivered to General Electric's Edwards AFB operation as a NB-58A. While there, a J93-GE-3 engine was installed in a special underfuselage pod.

Unfortunately, the F-108 interceptor was cancelled outright and the B-70 project was reoriented to a research project only. A few NB-58A ground runs were made with the J93 engine in place, but the day before the first flight was scheduled to take place, the funding for the NB-58A project was cancelled. Consequently, the NB-58A/J93 combination never took to the air. The special pod was removed from the NB-58 testbed, and the NB-58A itself was converted to a TB-58A and later flew chase missions for the XB-70A at Edwards AFB. It was consigned to storage at MASDC in 1970, and eventually scrapped in 1977.
Service of B-58 Hustler
By July of 1956, construction of the first B-58 was well underway. The name Hustler was officially applied to the aircraft at this time, although it had been used in-house at Convair for years before that.

The delays in the B-58 program were such that the development of the General Electric J79 engine caught up with the Convair airframe program and the initial flight testing with the J57 was found to be unnecessary. By August, the four YJ79-GE-1 engines had arrived at Convair. The YJ79-GE-1 was an early test version of the J79 and was nominally rated at 9300 lb.s.t. dry and 14,350 lb.s.t. with maximum afterburner. It was basically an experimental engine and was not capable of sustained operations with any regularity. Mean time between overhauls was very limited and numerous teething problems were encountered. It was, however, the first Mach 2-capable production turbojet in its class.

Two XB-58 prototypes were built (serial numbers 55-0660 and 55-0661). The first B-58, at that time officially designated YB/RB-58 and serialed 55-0660, was completed in late August, and was rolled out of the factory on September 4, 1956. It had little in the way of operational equipment fitted, the available space being taken up primarily by test equipment. 55-0660 made its maiden flight on November 11, 1956, taking off from the Convair Fort Worth facilities at Carswell AFB, Texas. The crew of three consisted of B. A. Erickson, pilot, John. D. McEachern systems specialist, and Charles P. Harrison as flight test engineer. The underfuselage pod was not fitted. The maximum speed reached on the first flight was Mach 0.9. Supersonic flight was first attained on December 30, at which time Mach 1.17 was attained.

Category 1 tests began in November, and lasted for about 3000 hours of flight time. On February 16, 1957, 55-0661 flew for the first time with a pod, a test MB-1 free-fall pod. On June 29, 1957, 55-0660, while carrying a "dry" MB-1 pod, reached Mach 2.03 at 43,350 feet. On June 5, 1957, the first pod drop took place, when 55-0662 released an MB-1 pod while flying at Mach 0.9 at 40,000 feet over the Holloman AFB test range. Successful drops took place at progressively higher and higher speeds, culminating on December 20 in a drop at Mach 2.0 from above 60,000 feet.

By the end of 1957, the YB-58 had attained a maximum speed of Mach 2.11 at altitudes over 50,000 feet. It had made two successful pod drops from 42,000 feet at speeds of over Mach 2. It had maintained a speed of more than Mach 1.15 for 91 minutes.

Eleven more aircraft were completed as YB-58 service test aircraft, which were used for various test programs, including flight testing with the large pod mounted on the lower fuselage. The YB-58As were modified several times, with some being converted to TB-58 trainers whereas others were brought up to B-58A production standards. Some serious problems were found. The J79-GE-1 engines installed on the first YB-58s pending certification of the J79-GE-5s had a number of flaws. Malfunctions in the fuel system caused the fuel to slosh around in the fuel tanks when the aircraft accelerated or slowed down, causing stability problems. Problems with the afterburners caused intermittent yawing at supersonic speeds. There were acousical and sonic fatigue problems caused by excessive vibration in the engines. These affected the aft area of the fuselage and would inevitably lead to testing restrictions unless corrected. Fatigue-related cracks began to appear along the rivet lines in the forward sections of the fuselage. There were problems with the wheel braking system. Because of inadequate heat dissipation while braking, tire failures were frequent during landings at high gross weights as well at high taxiing speeds. The ejection seats originally provided were usafe at high speeds due to insufficient thrust. Slippage in the bombing navigation subsystem development program promised a lengthy delay in the delivery of the initial service aircraft.

One engineless B-58 airframe (never assigned a serial number) was allocated to long-term fatigue testing. The airframe was delivered to the Wright Development Center Structures Test Laboratory at Wright Patterson AFB in Ohio by adapting B-36F 49-2677 as a transport, carrying the airframe underneath its fuselage in much the same manner as had been intended in the original parasite program. In order to do this, the B-36's inboard propellers had to be removed and a temporary shackle system was attached to the bomb hoist mechanism. The ground clearance for the suspended B-58 airframe was only 22 inches. This delivery took place on March 12, 1957. After delivery, four engines were added to the airframe to make the fatigue tests more realistic. The photographs released of the B-36/B-58 airframe combination were misunderstood by some who imagined that the B-36 actually launched the B-58 in midair.


The first YJ79-GE-5s arrived at Convair on September 27, 1957. Refuelling tests began on June 11, 1958. The B-58 proved to be entirely compatible with the KC-135 tanker.

Category 2 tests officially started in March of 1959, but actually began in February of 1958 since some tests normally done under Category I were done under Category II. This was because of the November 1957 decision to consolidate the B-58 test program under the weapons system office. These tests included pod drops and aerial refuelling. Category II testing was completed on June 30, 1960, after achieving 1216 flight hours in 256 sorties. Two YB-58As were flight tested from Edwards AFB, California and from Convair's Fort Worth airfield. Another aircraft went to Eglin AFB, Florida for climatic hangar evaluation. The accelerated service test of the J79-GE-5 engine was started under Category II, but completed under Category III when SAC crews accumulated 170 additional hours of flight. Some seven test aircraft were lost between December 1958 and June 1960, including one which disintegrated in flight.

The B-58 only carried one pilot and the three crew positions were in tandem. In flight, there was no physical access between the pilot's and navigator's compartments, which made training a student B-58 pilot very difficult. To solve this problem, the USAF ordered 9 YB-58As to be converted to trainer aircraft as TB-58A. One aircraft crashed before conversion, so only eight YB-58As wer actually modified.

On June 11, 1959, the Air Force announced that it planned to purchase 290 B-58s, including the 30 pre-production and test aircraft. They would be used to equip a 5-wing force. It was anticipated that the first tactical wing would be ready in November of 1960.

The first combat-ready production aircraft (B-58A number 31, 59-2428) was ready in the spring of 1959. In the meantime, the B-58 program was once again in jeopardy. On July 14, 1959, General Thomas Power was informed by the Pentagon that there were insufficient funds to satisfy all of SAC's needs. At that time, some 290 B-58s were scheduled for production, at a peak rate of 6 per month. There would have to be major cutbacks. By December of 1959, SAC had scaled back its plans and was now going to buy only 148 aircraft. The Pentagon was still unhappy with the current progress of B-58 development--major testing and operational dates had still not been met and many unsolved maintenance and engineering problems still remained, and there was insufficent money for adequate spare parts. Numerous specific problems remained with the AN/ASQ-41 bombing/navigation system and the AN/ALQ-16 electronics countermeasures system. The cost of the 118 aircraft now scheduled through FY 1961 was estimated at about 3 billion dollars, which made each B-58 literally worth more than its weight in gold. In addition, the the first operational squadron was now delayed from June to December of 1960 for activation, and the first wing of 36 rather than 45 aircraft would be ready in August of 1961.

Several accidents had revealed that the Convair-developed ejection seats were not sufficient to protect the crew throughout the B-58's performance envelope. Consequently, an encapsulated seat built by Stanley Aviation Corporation of Denver, Colorado was adopted.
A crew stands next to Convair airplane B-58 #96, the first production B-58 to fly with capsules in all three stations.

Due to the delays in the B-58 program, the various aircraft that had been delivered had great variation in equipment, systems updates, maintenance requirements, and capabilites. As a result, the USAF instituted the *Senior Flash-Up* program to update and normalize the aircraft in the inventory. The first aircraft to go through the program was delivered to SAC on November 7, 1960. Among the changes introduced were anti-icing systems, electronic countermeasures gear, an improved HACON and TACAN installations, a structurally improved vertical fin and fuselage embennage systems.

As the flight test program neared completion, the Air Force was faced with the problem of what to do with the flight test aircraft. Many of them had low times on their airframes and were hence still viable from a useful life standpoint. It was decided that these aircraft would be updated an configured for operational service under a program named Junior Flash-Up, which started in February of 1960. Later, other low airframe time pre-production aircraft were added to the program. Eventually, eleven of the 17 test aircraft produced under the second B-58 contract were upgraded.

The original order for YB-58As was altered and the last YB-58A aircraft were built as RB-58A reconnaissance aicraft. These aircraft were intended to carry a reconnaissance pod, but most were used in test programs along with the XB-58 and YB-58A aircraft. Most of the RB-58A aircraft were later brought up to B-58A productin standards and were issued to operational units.

On October 15, 1959, 58-1015 flew from Seattle, Washington to Carswell AFB in 70 minutes at an average speed of nearly 1320 mph. This was the first sustained Mach 2 flight.

The B-58 accident rate in 1959 and 1960 had been alarmingly high, which led SAC to delay acceptance of excecutive responsibility for the aircraft. The first accident had taken place on Dec 16, 1958, near Cannon AFB, NM when 58-018 was lost. The accident was attributed to a loss of control during normal flight when autotrim and ratio changer were rendered inoperative due to an electrical system failure. On May 14, 1959, 58-1012 was destroyed by fire during a refueling operation at Carswell AFB. 58-1017 was destroyed on September 16 of that year when a tire blew during takeoff from Carswell AFB. On October 27, 55-669 was destroyed near Hattiesburg, Mississippi when it lost control during normal flight. On November 7, 55-664 was destroyed during a high-speed test flight near Lawton, Oklahoma when it disintegrated in midair. Convair test pilot Raymond Fitzgerald and Convair flight engineer Donald A. Siedhof were both killed. The flight was attempting to collect vertical fin side loads data under the conditions of the loss of an engine at high speed. A friend of mine witnessed this accident from the ground. Although the cause of the accident was never adequately explained, it appears that a design flaw in the aircraft's flight control system and defects in the integrity of the vertical fin structure were to blame. There is also the possiblility that when the number 4 engine was purposely shut down for the test, number 3 lost thrust as well. On April 22, 1960 a failure of the Mach/airspeed/air data system caused the loss of 58-1023 near Hill AFB, Utah. On June 4, 1960, 55-0667 was lost due to pilot error while flying at supersonic speed near Lubbock, Texas.

The unusually high accident rate made SAC apprehensive about the reliability of the aircraft in service, and led to postponement of Category III testing. In addition, the Fitzgerald accident raised questions about certain aspects of the control system. As a result, B-58s were restricted to subsonic flight only for nearly a year afterwards until the control system and tail structure could be fixed.

By mid-1960, the combination of a shortage of funds, competition from other weapons systems, and a variety of technological difficulties had combined to cause a delay in the B-58's initial deployment. Although the aircraft had been scheduled to become operational in June, it appeared that the first wing would not be activated until January of 1961. SAC was still planning on three B-58 wings, since they concluded that a small, fully operational B-58 force would force the Soviet Union to develop a fleet of Mach 2 interceptors that would cover all possible targets or accept the amount of destruction that a three-wing force could inflict. Most of the major targets west of the Urals would be vulnerable to an attack by refuelled B-58s, with the B-52 and B-47 fleets providing mutual support for penetration of Soviet early warning and defense nets. With Mach 2 high altitude performance, the B-58 would greatly improve the overall strategic capability of SAC.

SAC had assumed that a three-wing B-58 fleet would be funded. The first two wings would be based at Carswell AFB and Bunker Hill AFB, but SAC was not sure where the third one would be located. General Power, Lt. Gen. J.P. McConnell, and other SAC officers argued that the third wing should be at Little Rock AFB in Arkansas. General Power asked his staff to start planning for the aircraft, along with a fleet of KC-135 tankers, to be located at this base.

In January of 1960, the USAF announced its intention to activate the first B-58 Wing. This was to be the 43rd BW, at that time based at Davis Monthan AFB in Arizona. The 43rd BW would be moved to Carswell AFB starting on March 1. The 3958th Operational, Test, and Evaluation Unit (then functioning as an integral unit at Carswell) would be transferred to the 43rd BW upon its arrival. On August 1, 1960, the USAF finally formally assumed B-58 operations responsibility and began Category III testing. 59-2436, the first fully-operational Hustler equipped with all tactical systems, was delivered to the 43rd. Two weeks later, the first TB-58A was delivered to Carswell AFB.

The 43rd BW received its first B-58 on March 15, 1960. On March 23, a test unit B-58A (55-0671), remained airborne for 18 hours 10 minutes while averaging an airspeed of 620 mph over 11,000 miles. This was apparently the longest-lasting single flight ever by a B-58. The 43rd BW received deliveries beginning in December of 1960. However, technical difficulties continued to plague the B-58, and on March 10, 1961 SAC had once again to set back the operational readiness date of the 43rd BW.

The second Wing to receive the B-58 was the 305th BW at Bunker Hill AFB. Equipping of the wing with B-58s began in December of 1960. Following official instigation of the reorganization of the unit on January 9, 1961 and its attainment of wing status on February 1, the first aircraft was flown to Bunker Hill on May 11. Two months later, the first TB-58A arrived. The wing was declared operationally ready in August of 1962.

In late 1960, the USAF decided to publicize the capabilities of its new B-58s by capturing a series of aviation records. The first of these was a project known as Quick Step I in which 59-2442 of the 43rd BW set three new speed-with-payload records (0, 1000 and 2000 kilogram payloads) by flying at a speed of 1061 mph over a closed circuit 2000-kilometer course on January 12, 1961. On the same flight, the crew also set a 1000-kilometer record by flying at an average speed of 1200.19 mph. The closed circuit and 2000-kg records still stand.

On January 14, 59-2441 set three international speed-with payloads by flying at a speed of 1284.73 mph over a 1000-km closed circuit. The crew of 59-2441 (Lt. Col. Harold Confer, Lt. Col. Richard Weir, and Major Howard Bialas) were awarded the 1961 Thompson Trophy for this feat.

On May 10, 1961, 59-2451 crewed by Major Elmer Murphy, Major Eugene Moses and Lt. David Dickerson, flew a 1073-kilometer closed course at an average speed of 1302.07 mph, taking 30 minutes and 43 seconds to complete the course. This won the Bleriot Trophy, which had been established back in 1930 by the famous French aviator M. Louis Bleriot to be awarded permanently to any aircraft flying for at least a half-hour at an average speed of 2000 km/hr (1242.74 mph).

On May 26, 1961, 59-2451, crewed by Maj. William Payne, Capt. William Polhemus, and Capt. Raymond Wagener, while enroute to the 1961 Paris Air Show, set a New York-to-Paris speed record, covering the 3626.46 mile route in 3 hours 19 minutes 58 seconds (an average speed of 1089.36 mph. The flight also set a Washington DC to Paris (3833.4 miles) speed record of 3 hours 39 minutes 48 seconds (average speed of 1048.68 mph). The crew was later awarded the prestigious Mackay and Harmon Trophies for this flight. Sadly, the return flight crew, consisting of Maj. Elmer Murphy, Major Eugene Moses, and Lt. David Dickerson (the same crew who had won the Bleriot Trophy two weeks earlier) were killed when 59-2451 crashed on June 3 following departure from Le Bourget Field.

Further records were set on March 5, 1962, when 59-2458 crewed by Capt. Robert Sowers, Capt. Robert Macdonald, and Capt John Walton set a trascontinental speed record by flying nonstop from Los Angeles to New York and back again. The first leg (Los Angeles to New York) was completed in 2 hours 0 minutes 56.8 seconds at an average speed of 1214.71 mph. The return leg was completed in 2 hours 15 minutes 48.6 seconds, at an average speed of 1081.77 mph. This return flight was particularly notable, because it was the first transcontinental flight in history that moved across the country at at a speed faster than the rotational speed of the earth.

The 43rd BW, which had been prevented from being declared combat-ready by the B-58's teething problems, was finally declared as such in August of 1962. The Wing was placed on alert in September of 1962.

On September 18, 1962, 59-2456, with a crew consisting of Major Fitzhugh Fulton, Captain W. R. Payne, and civilian flight test engineer C. R. Haines was used to set two more records. During a zoom climb over Edwards AFB, the aircraft reached an altitude of 85,360.84 feet while carrying a payload of 5000 kg, winning the crew the 1962 Harmon trophy. This broke two previous Soviet-held records.

On October 16, 1962, 61-2059 crewed by Major Sidney Kubesch, Major John Barrett and Captain Gerard Williamson, flew supersonically from Tokyo to London, spending five hours at supersonic speed. The flight set five world absolute records.

Just as the point of entry of the B-58 into active service, it was revealed that the number of B-58 wings was going to be one less than that which SAC had anticipated, and 30 aircraft ordered for FY 1962 were cancelled. A wing of B-47 Stratojets would be retained to offset the reduction. Unit cost of the B-58 had jumped to 14 million dollars, which made the aircraft almost three times as expensive as a production B-52G. The delays in the B-58 program had now put the Hustler in direct competition with the B-70 program for funding, and the B-70 was at that time pictured as the next step in the USAF's bomber program.

In spite of its initial teething troubles and the long delays in initial entry into service, by the mid-1960s, the B-58 had become a fairly effective weapons system. By the end of 1962, USAF crews had made over 10,500 flights and loges 53,00 hours (1150 of them supersonic, including 375 at Mach 2). Initially, B-58 training was conducted by the 43rd Combat Crew Training School. From 1960 through 1964, this unit fulfilled the requirements of both its parent 43rd BW and the 305th BW. In August of 1964, the 305th activated its own CCTS.

In a little-known attempt to increase the flexibility of the B-58 as a weapons system, experiments were carried out in April of 1964 under a program known as Operation Bullseye to see if the B-58 could carry and deliver conventional bombs. In coordination with Republic F-105Ds and McDonnell F-4C/Ds, sorties were flown using B-58s as lead ships and pathfinders and as independent strike aircraft. It was demonstrated that the B-58 could carry iron bombs on the wing root bomb racks that had earlier been added to accommodate four Mk. 43 nuclear weapons. Iron bombs of varying weights up to 3000 pounds were dropped, usually from low altitudes and at speeds of 600 knots. Almost all of the drops were visual, with the AN/ASQ-42 system rarely being used. However, the fear that the B-58's integral wing tanks would make it vulnerable to ground fire during low altitude delivery lead to the abandonment of the program.

The active service life of the B-58 was destined to be rather short. Phaseout of the B-58 fleet was ordered by Secretary of Defense Robert McNamara in December of 1965, since it was felt that the high-altitude performance of the B-58 could no longer guarantee success against increasingly-sophisticated Soviet air defenses. At that time, Secretary McNamara also announced that the FB-111A would be built. McNamara proposed that the new FB-111A, along with improvements in the Minuteman and Polaris missiles and modernization of the subsonic B-52 would enhance strategic deterrence and make the B-58 superfluous to the needs of the USAF. Although SAC had never been happy with the relatively limited range of the B-58 and felt that the Air Force through congressional pressure had forced the B-58 on them, the aircraft had gone through a long gestation period during which lots of bugs had been wrung out of the system, and it was now thought to be a valuable and effective weapons system. Consequently, SAC pressed the Defense Department for the retention of the B-58, at least until 1974. However, the decision of 1965 was to stand.

Another factor was the B-58's relatively high cost as compared to the B-52 and B-47. The unit cost of the B-58 was 33.5 million dollars as compared to 9 million for the B-52 and 3 million for the B-47. The cost of maintaining and operating two B-58 wings equaled the cost of maintining six B-52 wings. In addition, the B-58 was quite costly to maintain.

The B-58's high accident rate was probably its most serious failing. Out of the 116 aircraft built, some 26 were destroyed in accidents, and several additional aircraft were damaged seriously enough to prevent them from being returned to flight status. Most of the accidents took place during the B-58's flight test and operational evaluation period, with a lower attrition rate actually being attained late in its operational career. Many of the accidents were due to plain carelessness and were not the aircraft's fault, but others were a result of mechanical or systems failures that were basically a consequence of the B-58's rapid leap forward in technology. Nevertheless, there was more than a slight residual dislike for the aircraft among the SAC and USAF hierarchy.

On October 27, 1969, Secretary of Devense Melvin Laird announced a round of base closings. Included on the list were Little Rock AFB and Bunker Hill AFB (now named Grissom AFB, in honor of the astronaut Virgil Grissom who had been killed along with fellow astronauts Edward White and Roger Chaffee in the Apollo 1 capsule fire on January 27, 1967). Although these two bases would remain intact as military bases, they would lose their B-58 wings. The aircraft would be removed from the inventory and scrapped.

The first B-58 to go to the boneyards was 59-2446, which flew to Davis Monthan AFB on November 5, 1969. Once underway, the B-58 retirement program moved relatively rapidly. The retirement was completed on January 16, 1970, when the 305th Bomb Wing's last two B-58s (55-0662 and 61-0278) were flown to Davis Monthan AFB in Arizona for storage. Once their B-58s were in storage, the 43rd BW was temporarily inactivated, but was immediately reactivated with the assets of the 3960th Strategic Wing at Anderson AFB on Guam. The 305th BW was converted to an inflight-refuelling wing using KC-135As.

By the end of January 1970, all surviving B-58As and TB-58As were in storage at Davis Monthan AFB. Others had been placed in museums. After all salvageable equipment was removed, the 80-odd B-58s were apraylatted and stored at MASDC. Following over a half-decade sitting out in the Arizona desert, all of the MASDC Hustlers were sold at auction for scrap.

Only two USAF Bomb Wings operated the B-58:

305th Bomb Wing, Bunker Hill AFB (renamed Grissom AFB in May 1968)

364th Bomb Squadron (Medium)

365th Bomb Squadron (Medium)

366th Bomb Squadron (Medium)


43rd Bomb Wing, Carswell AFB

63rd Bomb Squadron (Medium)

64th Bomb Squadron (Medium)

65th Bomb Squadron (Medium)

(Text from here - https://www.crouze.com/baugher/ )

Below the first three Convair YB-58A-1-CF Hustlers

Below production







Below J-79 engine

Below Vulcan Gun of a Convair B-58 airplane.

Below view of the nose probe and gear of a Convair

Below Val Prahl sits in the cockpit of a Convair B-58 airplane with a notepad and pen. He had over 40 hours of flight experience on the plane.

Below Two men do assembly work on the right engine of a Convair B-58 airplane.

Below This Convair B-58, the Cowtown Hustler, arrives at Los Angeles at the end of its Bendix Trophy winning flight on 3-5-1962.

Below The flight crew of one of the Convair B-58 airplanes walks from their plane after a flight. Pilots Left to Right Grover Ted Tate; A. S. Doc A.S Witchell, and C.T. Jones.

Below The flight crew of one of the Convair B-58 airplanes walks away after disembarking. Pilots Left to Right A.S Witchell, G.C. Tate, and C.T. Jones


Below The crew of the Convair B-58 #64 Hoosier Hustler stand next to the airplane.

Below The crew of the Convair B-58 #64 Hoosier Hustler airplane stand together in the plane's cockpit.

Below The crew of Convair airplane B-58 #38 stand next to their plane on the day of the last B-58 test flight.

Below The crew of a Convair B-58 inspect the plane's landing gear prior to take-off for Edwards Air Force Base.

Below The Convair B-58 Hustler touches down at Le Bourget Airport in Paris, France. At the time it was the Trans-Atlantic Record-Breaker.

Below Rear view of a Convair B-58 airplane undergoing maintenance in a run station.

Below Pilots E.E. Guthrie, G.C. Tate and Norm Stanberg perform an escape test from a Convair B-58 airplane.

Below Night shot of three pilots sitting in the crew stations of a Convair B-58 airplane with the hatches open.

Below Maintenance crews load the underbelly pod of a Convair B-58 airplane.

Below Jim Wright, wearing full face-mask and gear, waves from the cockpit in a Convair B-58 airplane

Below J.W. McGaughy displays a gatling gun on a Convair B-58 airplane.

Below Gloria Tipton stands on a platform touching the image of Reddy Kilowatt emblazoned on surface of Convair airplane B-58 #25.

Below Flight line of Convair B-58 airplanes at Carswell Air Force Base.

Below Flight crews pose together next to a Convair B-58 airplane.

Below Crewmen make notes before flying the Convair B-58 airplane to Bunker Hill Air Force Base. Standing left to right Colonel F.L. O'Brien, Major G.V. Cohlmia and Major W.W. Wilson

Below Convair XB-36 airplane(left) and Convair B-58 (right) are taxied side by side on a runway.

Below Dick Johnson sits in the cockpit of a Convair B-58 airplane.

Below Convair B-58 airplane undergoes maintenance in Run Station #2



Below Convair B-58 airplane during take-off.

Below Convair B-58 #61 that won the Bendix Trophy on March 5, 1962 for record flights from New York to Los Angeles

Below Convair airplanes 880, B-58 and 106 flying together.

Below Convair airplane B-58 #64 sits outside a run station. It was the first airplane taken to Bunker Hill AFB.

Below Convair airplane B-58 #8 sits in a run station.

Below Convair airplane B-58 #8 in a run station.

Below Colonel F.L. O'Brien shakes hands with B.G. Reed upon receiving the Convair airplane B-58 #64 Hoosier Hustler. It is the first airplane taken to Bunker Hill Air Force Base.

Below Captain F.L. Fulton disembarks a Convair B-58 airplane after a flight.

Below Bottom view of a Convair B-58 airplane while flying.

Below Boeing KC-135 airplane refuels a Convair B-58

Below Bleriot Trophy Winners next to their plane, the Firefly, a Convair B-58 Major Elmer E. “Gene” Murphy, Major Eugene F. Moses, Lieutenant David F. Dickerson with Colonel James K. Johnson.

Below An Air Force flight crew wearing pressure suits stands on a ladder next to a Convair airplane B-58 #2.

Below A worker helps Convair airplane B-58 #38 tax into position after the last B-58 test flight.

Below A pilot runs towards another pilot who is climbing a ladder to the top of a Convair B-58 airplane at night.

Below A Convair B-58 airplane sits on display at the 30th Air Show at Carswell Air Force Base.

Below A Convair B-58 airplane sits next to an Atlas Missle laying on a ramp on the back of a truck.

Below 3/4 front view of a Convair B-58 airplane.

Below A group stands in front of the last Convair B-58 #116 airplane upon its last delivery.

Below Convair B-58A Hustler in colour













Below Convair TB-58A Hustler in colour