On June 4, 1968, Jack Weeks left Kadena in Article 129, with the intention of conducting an FCF; he completed a 34,000lb fuel on-load from the tanker, accelerated, and climbed away, and that was the last anyone ever saw of both pilot and aircraft. Forty-two minutes into the flight, the Birdwatcher-sensor system on the A-12 transmitted a signal to Kadena AB, indicating that the starboard engine EGT was in excess of 860 degrees C. Twenty-two seconds later, Birdwatcher indicated that fuel flow to the same engine was less than 7,500lb per hour. Just eight seconds on and a third and final transmission from Article 129’s Birdwatcher repeated the earlier information; this time, however, it ominously included data indicating that the aircraft was now at or below 68,500ft. From this limited evidence, it is reasonable to conclude that some kind of malfunction involving an over-temperature and low fuel flow on the right engine had somehow contributed to what appears to have been a catastrophic failure and subsequent aircraft break-up. Not a trace of wreckage was ever found and it was particularly ironic and an especially cruel twist of fate to lose such a highly competent and professional pilot on one of the very last flights of the Oxcart program.
During early June 1968, the two remaining Black Shield A-12s at Kadeana AB (Articles 127 and 131) were ferried back to Area 51 before being positioned to Palmdale. On reaching the Lockheed plant, company maintenance technicians drained all fuel and hydraulic lines, and Mel Rushing skillfully “interwove” all nine remaining Oxcart aircraft into a tightly regimented, sardine-like parking array in a corner of one of the large hangars, where they remained for more than 20 years before being dispersed to museums.
On June 26, 1968, Deputy Director of the CIA, Vice Adm Rufus Taylor, presided over a ceremony at Area 51 where he presented the CIA Intelligence Star for Valor to Ken Collins, Jack Layton, Frank Murray, Denny Sullivan, and Mele Vojvodich for their participation in Black Shield; the posthumous award to Jack Weeks was accepted by his widow. The Legion of Merit was presented to Col Slip Slater and to his deputy, Col Amundson. In addition, the Air Force Outstanding Unit Award was presented to members of the Oxcart Detachment, the 1129th Special Activities Squadron, also known as “The Road Runners.”
The long-standing debate as to whether Oxcart, or a program known as Senior Crown, should carry forward the manned strategic reconnaissance baton, had been resolved: the single-seat A-12 was vanquished; the new kid on the block was to be the Air Force two-seat SR-71A. In early March 1968, SR-71As began arriving at Kadena AB to take over the Black Shield commitment.
NASA operations
In 1967, a deal was struck between NASA and the Air Force whereby the former was given access to early A-12 wind tunnel data in exchange for NASA providing a small team of skilled engineers to work on the SR-71 flight-test program. NASA signed a memorandum of understanding with the Air Force on June 5, 1969, which permitted them access to the two remaining YF-12As then in storage. Phase one of the program was controlled throughout by the Air Force and got underway at Edwards AFB on December 11, 1969, utilizing YF-12A 60-6936. Essentially this phase consisted of developing possible bomber penetration tactics against an interceptor with the YF-12’s capabilities. It terminated on June 24, 1971, after the aircraft caught fire during the closing stages of the 63rd flight, whilst on base-leg at Edwards AFB. Fortunately both crewmembers safely ejected, but the aircraft crashed and was totally destroyed.
Whilst the YF-12As were being readied for flight two, NASA crews were checked-out by senior Air Force SR-71 crewmembers. Utilization of the high-speed platform proved to be high, since NASA engineers at Langley were interested in aerodynamic experiments and testing advanced structures; Lewis Research Establishment wanted to study propulsion, whilst Ames Research Center concentrated on inlet aerodynamics and the correlation of wind-tunnel and flight-test data. In addition, the aircraft was used to support various specialized experimentation packages.
Ultimately, 60-6935 continued operating until the program ceased after its 145th NASA flight on October 31, 1979. A week later an Air Force crew ferried the aircraft to the Air Force Museum (now the National Museum of the US Air Force) at Dayton, Ohio, where it is displayed as the sole surviving example of the YF-12A.
CONCLUSION
The failure to produce wide-band suppression of the U-2’s RCS during phase one of Project Rainbow — as required by President Eisenhower — generated the need to design and build a totally new replacement aircraft. It would be interesting to speculate what an eventual U-2 replacement aircraft would have looked like if the RCS conundrum had been solved back in the late 1950s!
Project Oxcart’s contribution should therefore be evaluated from two perspectives, namely execution of the strategic reconnaissance-gathering mission whilst operated by the CIA and as an aviation accomplishment.
As a strategic reconnaissance-gathering platform, Oxcart’s overall contribution to the CIA’s intelligence database was probably negligible compared to that made by other assets, such as the U-2 and satellites. However, this is not a fault of the aircraft per se, since it was US policymakers that decided not to employ the aircraft in the role for which it had originally been designed. The simple fact of the matter is that manned overflight of the Soviet Union following the May 1, 1960 U-2 shoot-down became politically unacceptable, so to a degree Oxcart became “an advanced anachronism.”
Some commentators have made operational cost comparisons between Oxcart and the U-2, but this is disingenuous. Yes, the U-2 was much cheaper to operate; however, as demonstrated over both the USSR and Cuba, the U-2 was vulnerable to interception by SA-2s and was therefore incapable of executing its mission in such an environment. This was not the case with Oxcart, as proven during Black Shield — it was able to complete its mission despite the presence of SA-2s.
During Black Shield, Oxcart provided US decision-makers with high-resolution, area PHOTINT coverage, proving there were no surface-to-surface missiles in North Vietnam. Its coverage of North Korea demonstrated that they were not planning some form of follow-up military action after seizing USS Pueblo. Black Shield also acquired timely invaluable PHOTINT of North Vietnam’s air defense network, and other war-related targets, enabling US military commanders to plan more effective bombing routes, which inevitably resulted in US lives being saved. But in so doing it could be argued that Oxcart was in effect being used as a tactical collection platform in a conventional military conflict — an activity that fell completely outside the CIA’s modus operandi.
However, when it comes to evaluating the A-12 or for that matter the YF-12 or latterly, the SR-71 in terms of aerospace design and performance accomplishments, the “Blackbird” family are without equal. More than 50 years after the first A-12 flight, they remain the fastest, highest-flying jet-powered aircraft ever built. Clarence “Kelly” Johnson and his team of Skunk Works aerodynamicists, thermodynamicists, electrical engineers, and physicists produced unrivaled innovations in aerodynamic design and metallurgy; and when it came to RCS suppression, they helped define the very foundations upon which future stealth research was based. Pratt & Whitney produced the unique, bleed bypass engine, whilst the Perkin-Elmer’s Type I camera produced image resolution of previously unheard of clarity.