B-58 Final Construction
While testing was going on, the B-58's fate once again appeared uncertain. A Rand Corporation study, requested by the Air Staff, proved disappointing. Rand thought that the B-52 was superior to the B-58 because the Boeing aircraft could carry heavier payloads and had a longer range than the B-58. Of course, the corporation agreed that air refueling was a means to extend range, but pointed out that such recourse could be unreliable and expensive. Instead, the cheapest way to solve the dilemma would be to equip the B-47s with improved engines. Penetration was another factor to be considered in assessing the bombers. However, in Rand's opinion, the aircraft's penetrative ability was unimportant since enemy defenses of the near future would be so sophisticated that bomber losses would be high, regardless of speed. While these observations appeared valid, the Air Force did not want to alleviate its financial difficulties through retention of an improved but still obsolescing B-47 fleet. The Air Staff, therefore, asked Rand to review its original conclusions. This second round of deliberations served no purpose. Rand returned its study unaltered and without any further solution.
Meanwhile, dissatisfaction with the B-58 program grew. The correction of obvious combat deficiencies was slow, and it seemed almost certain that early inventory aircraft would be short of components and would have no high frequency radio or identification equipment. Some SAC officials were beginning to think that 2 wings of B-58s would be plenty since the aircraft would require greater tanker support than the B-52s. Also, the B-58s would not be able to fly at low level without extensive and costly modifications. Others at SAC wanted more B-58s, having faith in the follow-on B-58B that could be expected to materialize after production of the first 105 B-58As (test-aircraft included).
In May 1959, after reendorsing continued production of the B-52s, as well as support of the B-70 and of the nuclear aircraft program, Genera! White refused to discuss the B-58's future. Just the same, the Air Force on 11 June 1959 began to plan the production and delivery schedules of 185 B-58Bs which, counting the B-58As, would increase the total to 290 aircraft, or enough to equip 5 wings. While at SAC, General LeMay had not liked the B-58A, and as Vice Chief of Staff, he did not change his opinion. The new model would be too expensive, its automatic equipment for low-level flight too complex. The B-58B was also due to provide increased range, speed, altitude, and external stores such as multiple free fall bomb pods, fuel tanks, and air-to-surface missiles.
On 7 July, the Air Staff eliminated the B-58B from the program and the B-58A itself again appeared to be in serious jeopardy. The 60 B-58As, under Letter Contract AF33(600)-38975 and due to be funded in fiscal year 1960, were first reduced to 32, then to 20. General Power tried to justify retaining the 290-aircraft program, but the Air Staff retorted that budgetary considerations were sometimes overriding and Secretary of the Air Force James H. Douglas confirmed that the B-58B was a dead issue. The B-58A came very close to following the B-58B's path. A saving factor again proved to be the money already invested in its development. Also, as noted by Secretary of Defense Thomas S. Gates, a redeeming virtue of the B-58A was its availability in the near term. Yet, even the latter justification was weakening. Time had been catching up with the B-58 weapon system, originally designed to perform against enemy targets of the 1958-1965 period. It was now obvious that the B-58A would not be available in quantity before 1962. Once at the top of the Air Force's priority list, the B-58A program had lost its urgency. In July 1960 (FY 61), Letter Contract AF33(600)-41891 was initiated, but the 30 aircraft and % BLU-2/B pods covered by the document were subject to cancellation. The Air Force reached a final decision in December 1960. The fiscal year 1961 purchase was retained, but the fiscal year 1962 procurement was deleted. SAC would receive 2 wings of B-58As and no more.
Category II test results and several accidents postponed Category III testing to August 1960, a 6-month slippage. SAC did not want to start the Category III tests before correction of certain B-58 deficiencies. Electrical malfunctions, tire failures, difficulties with the flight control system, and possible structural weaknesses appeared responsible for a rash of recent crashes. Accident findings did not indicate any consistency in the causes, but the B-58 remained under flight restrictions and SAC would not accept the aircraft pending further investigation. Supersonic speed restrictions were raised to Mach 1.5 in March 1960, but only for the aircraft equipped with modified flight controls. Also, modifications required by SAC had to be made to improve safety. By mid-1960, some structural improvements were completed. The aircraft tail had been strengthened, critical side panels had been reinforced, and an ARDC ad hoc committee report was given to SAC. The report emphasized that there were no design deficiencies in either the aircraft or the flight control system, and that when all functioned, the systems met the specifications. The report also noted that SAC pilots had verified the B-58's good handling characteristics, but pilot training and high proficiency were necessary. In addition, maintenance and control personnel should be highly skilled since those areas could greatly affect B-58 operations.
Obviously satisfied with the committee's report, SAC on 1 August 1960 assumed executive management of the B-58, a function previously vested in ARDC. This marked the beginning of Category III testing, which was accompanied by a number of changes. For example, ARDC's 6592d Test Squadron was inactivated, and the squadron's aircraft and personnel were transferred to the 65th Bombardment Squadron (Medium) of SAC's 43d Bomb Wing. The B-58 Test Force was formally dissolved, although a small nucleus of ARDC people stayed at Carswell AFB to assist the 43d Wing through completion of the Category III tests.
SAC's 3958th Operational Employment 'li=sting and Evaluation Squadron had been a most important member of the now extinct test force. The 3958th was responsible for the proper development of a combat crew training program. It had to select and educate B-58 maintenance personnel and to create a cadre of flight crews that would serve as instructors in forthcoming combat crew training classes. In addition, the 3958th put together standard operating procedures for the future B-58 wings. When it took over, SAC's 65th Bombardment Squadron (Medium) found no fault in the 3958th's performance. Formal 3-month classes for combat air crews, started in mid-1960, encountered no personnel difficulties. Selected students, former B-47 pilots and regular officers for the most part, were highly qualified, with a minimum 1,000 hours of jet flying experience. Student navigators, with 500 hours of flying time on multi-jet aircraft, and defense system operators, with a minimum of 200 hours, were also excellent candidates. The 65th Combat Crew Training Squadron used Convair 2-place TF-102As to start training B-58 pilots and welcomed the August 1960 delivery of the first TB-58A trainer. As a rule, 3 TB-58 flights were made before a pilot could solo in a B-58A.
Even though nearly 1,879 combat crew training hours were flown as part of the Category III tests, the program had little to do with the 43d Bomb Wing's combat crew training. The Category III task was to evaluate the overall operational performance of the B-58A. Since the aircraft was a highly integrated, complex weapon system, the scope of the Category III tests was unusually broad. The tests covered all aircraft systems, passive defense, electronics, communications and the like, but also aerospace ground equipment and supply, for all these factors played a part. Still, because of its critical importance, a great portion of the Category III tests was devoted to the ASQ-42V Bombing-Navigation Electronic System. Ended on 31 July 1961, after the loss of 1 more B-58, Category III testing was credited with some 5,265 hours of flying time, of which about 945 hours were used strictly for testing. The rest was accumulated in various ways. A subtotal of 1,878 hours was flown to meet various Category III combat crew training objectives. The remaining hours, approximately 2,439 of them, encompassed maintenance test flights, the acceptance and delivery flights of new and retrofitted B-58As, airshows and record-breaking flights, and the hours flown for ferry missions.
B-58As, a first lot of 12, began reaching the 43d Bomb Wing at Carswell AFB in August 1960, but the 43d did not gain an initial operational capability until 1961, and waited until May of that year to get its full complement of 36 B-58s. In later years, this number was increased to 45, a total which included 4 of SAC's 8 TB-58As. The other 4 trainers went to SAC's second wing of B-58s. An unreliable bombing and navigation system, maintenance difficulties, shortages of ground equipment, and continuous involvement in the Category III tests combined to delay the 43d Bomb Wing's combat readiness. A second SAC wing, the 305th at Bunker Hill AFB, Indiana's received its first new bombers in May 1961 to start converting from subsonic B-47s to supersonic B-58s. SAC had earmarked the 305th as the first B-58 recipient. Initially, this was changed as a result of the new testing arrangement. Later, the 43d Bomb Wing's proximity to Fort Worth remained an important factor in view of the B-58's early operational problems. SAC expected that the 305th would have its full allocation of B-58s by May 1962. 'Iiventy KC-135 tankers were already in place at Bunker Hill. Aerial tests, completed in October 1959, showed that Boeing KC-135 tankers could refuel the B-58s. However, air refueling training and operations were limited at first because the B-58 search radar was not compatible with the refueling rendezvous equipment installed in the KC-135.
The first 47 B-58As did not have tactical air navigation (TACAN) electronics. The system, developed by the Hoffman Laboratories, was provided as government-furnished equipment and due to be retrofitted in most of these early planes. Also, the B-58As could not fly at low levels. Design changes to give the aircraft this added performance were being worked out. Prompt results could not be expected since the changes had only been authorized in mid-1959, when Convair's subsequent model series, the improved, low-level flying B-58B, was canceled. There were many other deficiencies of varying importance. The aircraft's ejection seats were still unsatisfactory. Development of a capsule-type of escape system for a single crewman, now handled by the Stanley Aviation Corporation, was progressing well. However, the capsule's stability remained marginal after ejection, thereby preventing Convair from incorporating the capsule during production. This meant that all B-58s would have to be retrofitted, a task started in late 1962. The B-58 was the first aircraft with individual escape capsules for emergency use at any speeds. This escape system could rocket the crew to safety from anywhere between ground level at 120 knots and 70,000 feet at Mach 2.2. The capsule, fitted with clam-shell doors, was pressurized. Once sealed and ejected, it stabilized itself and descended by parachute. It was equipped with a flotation system that deployed automatically in the event of a landing on water. The capsule was not large, restricting the size of the crew. Even so, the capsule consumed space and made the B-58'5 small crew compartments more cramped. Meanwhile, another retrofit project was taking place. B-58As were re-equipped with sturdier wheels and new tires, marking the end of at least one long-standing problem. The loss of a B-58A on 16 September 1959 (totally destroyed by fire after an aborted take-off from Carswell) was directly attributed to tire failure, followed by disintegration of the wheel. But this was just a beginning. In mid-1961, following completion of a 6-month study, the Air Staff decided that much more would have to be done to enhance the B-58A's performance. It also approved modification of existing B-585 (about 70 of them) to allow the aircraft to carry a greater variety of weapons, 4 of which would be transported externally. Subsequent B-58As would be so equipped on the production line.
Significant modifications were initiated in November 1962, under the code name of Hustle Up, a 2-phase project accomplished in Fort Worth by the prime contractor, and in San Antonio, Texas, by technicians of one of the Air Force Logistics Command's air materiel areas. The first phase of Hustle Up covered 59 B-58As; the second phase, only 36. However, Phase II also modified 76 pods of various configurations. Modification kits, including aircraft kits, pod kits, training kits and kit spares, were acquired through special contract at a cost of $6.1 million and used by both the Convair people and personnel of the San Antonio Air Materiel Area. Retrofitting the escape capsules and installing multiple weapons proved to be the most extensive modifications covered by Hustle Up, which was completed in May 1964. Meanwhile, contrary to SAC's hope that the development program would yield a trouble-free aircraft, the B-58A weapon system was again encountering more than its share of difficulties. TWo fatal accidents and 30 in-flight "incidents" between March and September 1962 imposed new flight restrictions and generated another major modification program. This program, centering essentially on the aircraft's flight control system, was also conducted in several phases. Phase I put a gang bar on yaw damper switches, but provided minimal improvements. Phase II (redesignated Phase I, following the May 1963 completion of the program's initial phase) modified the mach altitude repeater and improved the unreliable amplifier computer assembly circuitry, thereby allowing the B-58As to fly again at speeds up to Mach 1.65. Started in April 1964, the new Phase I closed before year's end, as scheduled, with 13 B-58s of the 305th Bomb Wing being so improved while undergoing the last part of the Hustle Up modification program. The next phase (Phase III, now known as Phase II) did not fare as well. It was due to further improve the flight control system, which in turn would allow the B-58A to use its desired Mach 2 speed. Many costly changes were involved, totaling $30 million. Furthermore, this phase was not intended to take place before the fall of 1966.
Besides its obvious shortcomings, the B-58A was plagued from the start by a very serious problem. Its bombing and navigation system (the AN/ASQ-42) was far less reliable than that of the B-52 and the B-47. The problem, confirmed during Category III testing, did not lend itself to easy solutions. The AN/ASQ-42 was extremely complex. Its electronic signal loops were generated and circulated within several interconnected electronic "black boxes." Thus, malfunctions were hard to track down, since it was difficult to identify which black box was primarily responsible for the failure. By 1965, the AN/ASQ-42 had become an old problem, with no remedy in sight. Occasionally, malfunction causes were identified, but more often, they were merely suspected or totally undetermined. That the AN/ASQ-42 system had to be made to work well was obvious. Tb begin with, it was SAC's most sophisticated bombing system. Also, once fully operational, the AN/ASQ-42 would allow the B-58A to find and bomb any target, be it at high-altitude/supersonic or low-altitude/subsonic speeds. Yet, improvement proposals, submitted by various contractors in September 1965, were found unacceptable. They did not meet requirements, carried no guarantees, and fluctuated around $70 million, twice the anticipated cost. In any case, circumstances beyond SAC's control raised doubts about the AN/ASQ-42's potential performance.
In December 1965, Secretary of Defense Robert S. McNamara directed phaseout of the entire B-58 force by the end of June 1970. The decision followed completion of a study of the comparative costs and performance of a proposed bomber (the FB-111A) and existing B-52 and B-58 strategic aircraft. Secretary McNamara also publicly announced that the FB-11 IA would be built. The FB-111A medium-range strategic bomber, like the B-58, was built in Fort Worth by the Convair Aerospace Division of the General Dynamics Corporation. The FB-111A, a modified version of the F-111A tactical fighter, was part of an interrelated and highly controversial program. The new bombers, along with improvement of the Minuteman and Polaris missiles and modernization of the B-52, would enhance strategic deterrence and make longer retention of the B-58s superfluous. In addition, Defense officials deemed necessary budget cuts another valid factor. Appalled by the decision, SAC pointed out that the B-58A, after coming off production with many weaknesses, was well on its way to becoming a sound, effective weapon system. Stressing the declining number of manned bombers, SAC in the ensuing 2 years kept pressing for retention of the B-58s, at least until June 1974. But the decision of 1965 was to prove unshakable. On 21 February 1968, General McConnell, Air Force Chief of Staff since I February 1965, reaffirmed before the Senate Armed Services Committee that the entire B-58 fleet would be phased out before June 1970. And while it did not spell the end of the modifications programmed at the time, the overall B-58 improvement program was immediately affected.
Modifying the B-58A for low-level flying would be a meager improvement if the aircraft were not properly equipped. SAC insisted from the start that the B-58A, to be truly effective at low levels, needed a terrain-following radar to penetrate increasingly fierce enemy defenses. Prototype development of the radar, approved with misgiving in view of the entire venture's cost and technical hazards, was the first casualty of the B-58's early phaseout. It was canceled in late 1965, when SAC settled for a reliable radio altimeter and a forward-looking visual sensor (day/night television) system. This much less expensive project, installation and modification included, was completed in early 1969. Another modernization project had an even more disappointing fate. The B-58A's electronics countermeasures systems, never updated since the aircraft's production, were nearly obsolete. Should the high-altitude B-58A be committed to combat, it would be extremely vulnerable to surface-to-air missiles, such as the SA-2s. Several contemplated modifications had been held in abeyance pending the development of better techniques. One of them, modification 1180, had been approved in mid-1966 and would give the B-58A a new version of the ALQ-16 trackbreaker. However, when flight tested in 1968, this component did not work. As to other penetration aid improvements, they had not even reached the testing stage. Ongoing talks that the B-58s might, after all, be retained through 1974 kept the electronic countermeasures improvement projects alive until the end of 1969. When the B-58's longer retention did not materialize, all penetration aid modifications were canceled.
Retirement of the B-58 by mid-1970 meant that modifications, even if approved, would be deleted if not funded by mid-1968. Aware that several B-58 problems would take a long time to solve, SAC asked for a waiver of the so-called 2-year utilization rule, but the request was denied. Nevertheless, many of the modifications, pursued all along by SAC, came to fruition. After numerous setbacks, a solution was found for the B-58A's erratic flight control by adding a redundant yaw damper to the system. Retrofit kits were purchased in 1967, and the installation undertaken in May 1968 progressed smoothly. During the same period, an improved version of the AN/ASQ-42, flight tested in mid-1967, proved successful. Production of the improved system, approved on 27 September 1967 and funded within prescribed time limits, foretold no problem. Technical data and the delivery of spare parts had been included in the necessary contract. Moreover, installation of the system, as started in May 1968, was not expected to disrupt significantly SAC's operational plans. Another modification had also been sought by SAC, almost since the aircraft had become operational. The command wanted the B-58A crew to be capable of starting their engines without having to depend on pneumatic ground starting carts. Equipping the aircraft with a cartridge self-starter would allow it in an emergency to take off from dispersal, post-strike, and other remote bases. Yet the project had been handicapped from the start. It was approved, canceled, reapproved, modified, and constantly hampered by technical difficulties. SAC, nonetheless, won its case and the B-58 was equipped with a cartridge self-starter. The installation began on 7 May 1968, approximately 6 months after all B-58s had exchanged their J79-5B engines for improved J79-5Cs.
In mid-1965, the San Antonio Air Materiel Area recommended a program of inspect and repair as necessary (IRAN) for a scheduled, comprehensive depot-level inspection of the B-58. So far, San Antonio and SAC had taken care of the aircraft's difficulties as they arose. However, increasingly serious problems were being uncovered. The plumbing and wiring of the B-58As and TB-58As were deteriorating, and the aircraft were also showing signs of structural fatigue and corrosion. SAC had no objections to the IRAN program proposed for the B-58, a routine procedure for most aircraft. Nor did it object to the 36-month cycle favored by the materiel area. However, the command qualified its approval. Since fuel leaks indicated that corrosion was further along than estimated, corrective action could not await the January 1966 implementation of the IRAN program. Also, B-58s of the 43d Bomb Wing should be treated first, which they were. Initially conducted from Convair's Fort Worth facilities, the IRAN program was moved in mid-1967 to James Connally AFB, near Waco, Texas. There were no other changes. The B-58 modification/IRAN program was thorough. Major tasks included removal of all releasable panels; inspection and repair of the aircraft's primary and secondary structures; and inspection and repair of all wire bundles and cables, hydraulic lines and fittings, and air conditioning and pressurization duct components. The program also included bench testing and calibration of all electronic units, removal and overhaul of landing gear assemblies, and repair and treatment of corroded areas. This work consumed 16,000 manhours. In 1967, the cost per aircraft totaled $181,000; $201,000in 1968.
Production ended in the fall of 1962, with the last 3 B-58s being delivered on 26 October, 1 month ahead of schedule. All B-58s were built at the contractor's Fort Worth plant. The Air Force accepted 3 B-58s in FY 57; 8 in FY 58; 16 in FY 59; 11 in FY 60; 30 in FY 61; 33 in FY 62; 15 in FY 63 (the last 3 in October 1962). Research, development, evaluation, and testing cost, $1.4 billion. Cost per aircarft was: $12.44 million: Airframe, $6,447,702; engines (installed), $1,117,120; electronics, $1,294,791; ordnance, $26,674; armament (and others), $3,555,573.63
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