by Bill Yenne
The only losses during those four nights were two that occurred on December 21. On both December 22 and 23, the bombers feinted toward one target before making a sudden turn toward another. The missions of December 22–24 were against unpredictable targets, so the enemy had lost the ability to lie in wait with their most potent defenses.
The mission of December 24, Christmas Eve, repeated the scenario of the previous two. Once again, thirty BUFFs, this time all from U-Tapao, went out, struck rail yards at Thai Nguyen and Kep, 40 miles north and northeast of Hanoi, and returned unharmed. Two of the cells were attacked unsuccessfully by MiGs, with one MiG-21 shot down by Airman First Class Albert Moore, the second B-52 tail gunner to get a confirmed MiG kill during the Vietnam War.
On Christmas Day, the entire B-52 force paused for a twenty-four-hour halt in what the world press was now calling “the Christmas bombings.” The Nixon administration also suggested that the stand-down would be an opportunity for the North Vietnamese to reconsider their intransigence at the Paris peace conference.
Sgt. Samuel Turner, a B-52D tail gunner, was awarded the Silver Star for shooting down a MiG-21 on December 18, 1972, near Hanoi. It was one of only two enemy aircraft ever downed by a BUFF gunner. USAF
Bombs are loaded aboard BUFFs during Operation Linebacker II. USAF
They didn’t.
Linebacker II resumed on December 26 with another maximum effort involving 120 BUFFs, 78 of which took off from Andersen. They attacked in ten waves, hitting Haiphong, and seven separate target complexes in Hanoi. Unlike the earlier hundred plane raids, which were spread out over several hours, the entire December 26 force hit their targets in the space of fifteen minutes, pushing enemy defenses to the limit. The strike package was preceded by tactical aircraft attacking SAM and antiaircraft artillery batteries.
Of 113 bombers who arrived over the target, only 2 were lost to SAMs. The absence of the SAM missile batteries that had been taken out by B-52s on the December 23 raids saved lives on December 26. Meanwhile, ECM had also been refined by teams working around the clock since the first missions. Indeed, no aircraft were lost from a three-plane cell using mutual ECM protection. The two that were lost had been from cells whose third member had been forced to turn back prior to arriving over the target.
For the next three nights, the maximum effort was stepped down to sixty BUFFs each night, half of which flew out of U-Tapao and half from Andersen. Mission planners called for all sixty of the bombers to release their bombs in a ten-minute time span.
The attack on the night of December 27 targeted supply dumps, rail yards, and SAM batteries on the north and south sides of Hanoi. Also struck was Lang Dang, the principal choke point on the main rail line leading in from China, which made it a key strategic objective. The two BUFFs lost that night to SAMs were the last B-52s lost to enemy fire during the war.
A B-52D Stratofortress is silhouetted against the sun, as it flies over the cloud-covered Pacific Ocean. USAF
By the following night, the B-52 operations were becoming routine, even as the damage on the ground mounted. In the beginning, the North Vietnamese were launching around two hundred SAMs nightly, usually in salvos. On December 29, they were able to launch just twenty-three.
The last bomb of Linebacker II fell at seventeen minutes before midnight on December 29, 1972, bringing to a close the most intensive strategic air offensive since World War II. In 729 missions, the B-52s had dropped 15,000 tons of bombs and had dodged more than 1,200 SAMs. There had been fifteen BUFFs shot down, eight crewmen killed, thirty-three captured and later repatriated, and twenty-five missing in action.
In their wake, the bombers left nearly all of North Vietnam’s electricity generating capacity in shambles and a quarter of its petroleum reserves destroyed. Rail lines had been cut in five hundred places, with several hundred locomotives and railcars put out of business. Though Hanoi and Haiphong felt the brunt of Linebacker II, perhaps the most telling effect was felt half a world away at the Paris peace talks, which resumed on January 8, 1973, with an agreement signed finally on January 27.
Although in the shadow of an operation like Linebacker II almost any other operation is anticlimactic, the Arc Light missions did continue. The last B-52 missions against both South Vietnam and North Vietnam (south of the 20th parallel) were flown on same day that the Paris peace accords were signed. The last B-52 missions over Laos were flown in mid-April. The BUFFs continued to fly missions over Cambodia against the rebel forces advancing on Phnom Penh until they were halted by the congressional ban on bombing. The last B-52 sortie in Southeast Asia was flown there on August 15.
If Linebacker II had not ended the war, it had proved once again that strategic air power had the potential to be the decisive factor in the defeat of an enemy. The B-52, meanwhile, proved to be one of the war’s most important weapons. When used to project strategic air power, BUFFs drove the North Vietnamese to seek a ceasefire and sufficiently throttled their war-making capabilities so that they were unable to launch another major offensive for more than two years.
Linebacker II: Sorties Day By Day
A SAC crew runs toward a B-52H Stratofortress during a flight alert at Grand Forks AFB in April 1981. USAF photo, Master Sgt. Bob Wickley
THE 1970S WOULD BE a decade of consolidation, as most Stratofortress variants were retired and remaining variants upgraded. For eight years, the SAC B-52 fleet had operated with one foot in the world of conventional bombing operations, while still maintaining its nuclear deterrent mission. Ironically, those same years saw a dramatic decrease in the overall size of the fleet. In December 1965, even as the B-52Ds were being improved for the start of their role in the Southeast Asia conflict, Robert McNamara announced a long-term Stratofortress phaseout program.
His plan was that most Stratofortresses would be sent to join the entire B-58 fleet in long-term storage at the boneyard of the Military Aircraft Storage and Disposition Center (MASDC) at Davis-Monthan AFB in Arizona. Though the process was slowed during the war, it nevertheless continued.
SAC had maintained a fleet of around 600 Stratofortresses through the first half of the 1960s, but thereafter, a rapid rate of retirements brought the total to 505 in 1969, and 402 by the time of Linebacker II in 1972. With a few exceptions, the B-52Bs were out of service by 1966, followed by most B-52Cs and B-52Es by 1971. Some high-time war-veteran B-52Fs were retired by 1968, though the last few B-52Fs were not gone until the end of 1978.
Meanwhile, the two longer-range, second-generation aircraft, the B-52G and B-52H, would be retained. So too would the B-52D, in which so many improvements had been made to optimize it for conventional weapons delivery. As noted in the previous chapter, the upgrades made during Arc Light had actually made the B-52D more capable than the B-52G with regard to electronic countermeasures.
By 1978, thirty-seven high-time B-52Ds were retired and sent to MASDC, but eighty B-52Ds were earmarked for extensive modifications under the Pacer Plank program. Undertaken by Boeing, Pacer Plank included partial reskinning of the wings and fuselage, as well as wing pylon modification. As William Holder points out in the July-August 1978 issue of the Air University Review, “a surprising phenomenon resulted from the Pacer Plank modifications. The new wing skin is much cleaner aerodynamically than the skin it replaced, resulting in considerably less drag. Even though the modified plane weighs about 3,400 pounds more, its cruise range has been increased by three percent.”
The Pacer Plank B-52Ds remained active until being retired in 1982–1983.
Meanwhile, the B-52G and B-52H were also in need of improving. The Linebacker II experience, in which six B-52Gs were lost to North Vietnamese SAMs, pointed out serious shortcomings in the aircraft that was intended to penetrate Soviet air defenses if the Cold War turned hot. With this in mind, the B-52G and B-52H aircraft were the subject of numerous upgrades during the 1970s, including the Phase VI ECM Defensive Avionics Systems retrofit, better known as the Rivet Ace program.
B-52s
in the SAC Inventory: Draw-down and Early-Model Retirement Era
Numbers exclude aircraft not assigned to SAC
Undertaken between 1971 and 1976, the Phase VI Rivet Ace bore some similarity to the Phase V Rivet Rambler program of the late 1960s, as they both included the AN/ALT-32H high-band and AN/ALT-32L low-band jammers, and the AN/ALR-20A wideband countermeasures receiver. They both included the AN/ALT-16 barrage jamming transmitters, though the Rivet Ace AN/ALT-16A was driven by the AN/ALQ-122 false target generator system.
Both upgrades included retrofitting eight AN/ALE-24 chaff dispensers, with a total of 1,125 bundles of chaff, but while Rivet Rambler incorporated six AN/ALE-20 flare dispensers, the Linebacker II experienced dictated double that number under Rivet Ace. Other important components of Rivet Ace included the AN/ALQ-117 active countermeasures system, AN/ALQ-153 tail-warning radar, and the AN/ALT-28 jamming transmitter.
The package also included the Litton AN/ALR-46 digital radar warning receiver, AN/ALQ-117 active countermeasures, and the AN/ALQ-153 tail warning radar.
Among the most noticeable upgrades was the installation of the AN/ASQ-151 Electro-optical Viewing System (EVS) to give crews improved visibility at low level during nocturnal operations. The EVS included a Westinghouse AN/AVQ-22 Low-Light-level Television (LLTV) camera, and a Hughes AN/AAQ-6 Forward-Looking Infrared (FLIR) sensor, both located in conspicuous fairings on the underside of the forward fuselage.
Meanwhile, the parallel Quick Start program of 1974 retrofitted the B-52Gs and B-52Hs with cartridge starters, which permitted a simultaneous ignition of all eight engines.
By 1976, the B-52Gs and B-52Hs had been upgraded with the Phase VI ECM Defensive Avionics Systems package, as well as the AN/ASQ-151 Electro-optical Viewing System. Beginning in 1980, the Stratofortress’s offensive avionics were replaced by newer equipment. The ancient analog AN/ASQ-38 bombing-navigation system was superseded by the AN/ASQ-176 Offensive Avionics System (OAS), which had solid-state digital electronics. This package included the AN/ASN-134 attitude heading reference system, the AN/ASN-136 inertial navigation system, AN/APN-218 Doppler radar, and the AN/APN-224 radar altimeter.
A Phase VI–Plus ECM upgrade followed in 1988, which involved the AN/ALQ-117 Pave Mint active countermeasures system being replaced by the improved AN/ALQ-172(V)1 in the B-52G and the AN/ALQ-172(V)2 in the B-52H.
The Postwar Role of the Stratofortress
By the late 1960s, the Stratofortress was an established component of a three-part nuclear deterrent force that was known as the Strategic Triad. The other prongs of the Triad were both solid-fueled missiles with intercontinental range: Intercontinental Ballistic Missiles (ICBMs), also under the command and control of the Strategic Air Command; and Submarine-Launched Ballistic Missiles (SLBMs), controlled by the U.S. Navy. The two missile types were deployed throughout the decade, superseding an earlier generation of inefficient liquid-fueled ICBMs. By the early 1970s, SAC was deploying its multiple-warhead LGM-30G Minuteman III, and the U.S. Navy, its long-lived UGM-73 Poseidon.
The Triad, despite involving strike forces of two separate branches of the armed services, operated under a Single Integrated Operational Plan (SIOP). This frequently updated document assigned priorities to target lists and specified detailed mission plans for each leg of the Triad. Revised annually, the SIOP originated in 1962, superseding the National Strategic Target List (NSTL), which had originated at the White House level in 1960. The SIOP continued to be updated past the end of the Cold War, being replaced by the Operational Plan (OPLAN) in 2003, which has since reportedly been superseded by the multiple Contingency Plans (CONPLAN).
A SAC B-52D Stratofortress overflies the Soviet aircraft carrier Kiev while on a routine maritime reconnaissance mission over international waters. USAF
Stratofortresses undergoing routine maintenance in November 1977 at the Oklahoma Air Logistics Center at Tinker AFB. USAF photo, Sgt. Deal Toney
The BUFF pilot “paints” a picture of California’s Mount Shasta (visible in the distance) using his aircraft’s AN/ASQ-151 Electro-optical Viewing System. Unnecessary in broad daylight, the capability was very useful during low-level operations at night. This system was state of the art in 1980. Bill Yenne
The view from the right seat of a 328th Bombardment Squadron B-52H as photographed by the author during a low-level training mission over the First Combat Evaluation Group Detachment 5 range near Wilder, Idaho, on June 25, 1980. Bill Yenne
Each successive SIOP was drafted against the backdrop of increasing Soviet nuclear capability. In the mid-1960s, the United States had a four-to-one lead over the Soviet Union in ICBMs, but the ratio inverted to favor the Soviets three-to-two in both ICBMs and SLBMs during the 1970s, with new weapons being developed and produced at a rapid rate. The United States still had a three-to-one lead over the Soviets in strategic bombers, but that was primarily the dwindling B-52 fleet. The mainstay of the Soviet fleet was still the Tupolev Tu-95, codenamed Bear by NATO, which is seen by many as having originated as a knockoff of the turboprop Boeing Model 464-35.
The Ongoing Quest For a Successor
During the early days of the SIOP, Secretary of Defense McNamara had made no secret of his fondness for a reliance on missiles, rather than manned bombers, and so he put a low priority on this point of the triad.
The Achilles heel of the manned bomber, as McNamara pointed out, was the growing capability of Soviet air defenses. Designed as a high-altitude bomber, the B-52 had to compromise and be adapted to fly at low level to penetrate these defenses. As for air defenses, the specter of the six BUFFs lost during a single night during Linebacker II still haunted strategic planners despite post-Vietnam Rivet Ace upgrades in B-52 ECM capabilities.
By the 1970s, the sprawling Soviet air defense network was far more sophisticated than that which SAC crews had faced in Linebacker II. It included 6,000 radar installations from Murmansk to Vladivostok and 12,000 SAMs in around a thousand locations. Meanwhile, the Soviet interceptor force was estimated to include 5,000 aircraft, including the Mach 3 MiG-25 Foxbat, which entered service in 1970, and which had “look-down/shoot-down” radar to permit attacks on low-flying B-52s.
The copilot’s station in a retired B-52D. Note that the “hood ornament” in the center of the yoke, highly valued by collectors, has been removed. Bill Yenne
The North American Aviation XB-70 Valkyrie was intended by the SAC to be the prototype for the successor to the Stratofortress in the 1960s, but was canceled by President John F. Kennedy as “unnecessary and economically unjustifiable.” USAF
Harold Brown, called “the Father of the B-1” for his advocacy of the Advanced Manned Strategic Aircraft program while chief of research and engineering at the Pentagon in the Johnson administration, was instrumental in killing the B-1 program while Secretary of Defense in the Carter administration. DoD
The SAC insignia was prominent on the nose of the first Rockwell B-1 when it rolled out from Air Force Plant 42 at Palmdale, California, on October 26, 1974.
The second B-1A aircraft was reconfigured to serve as the testbed for the B-1B Test Program at the Air Force Flight Test Center at Edwards AFB in 1983. USAF photo, Samuel Hotton
In September 1987, during the author’s visit to Palmdale, the B-1B Spirit of Abilene was being finished up for its final delivery flight to SAC’s 7th Bombardment Wing at Dyess AFB near Abilene, Texas. Bill Yenne
As for a new generation of bombers, it had been assumed when the YB-52 first flew that the entire Stratofortress fleet would have been superseded by another aircraft type well before the 1970s. The B-52 had began replacing the B-36 in SAC service by 1956, only eight years after the B-36 had first entered service, but McNamara consistently rejected serious discussion of a new intercontinental-range jet bomber. By the middle of the 1960s, the supersonic B-58 was phased out, and the XB-70 program was cancelled without going beyond the two prototypes.
The issue of a successor to the B-52 had been a persistent topic of conversati
on from the industry design rooms to the Pentagon throughout the 1960s as the B-58 and XB-70 came and went—and as McNamara limited the Advanced Manned Strategic Aircraft (AMSA) program to a series of lengthy studies. In 1969, SAC began receiving the first of more than sixty General Dynamics FB-111 aircraft, a longer-winged variant of the F-111 fighter, but these aircraft were seen as an “interim” bomber and never as a successor to the B-52.
Dozens of Stratofortresses, including many B-52Cs, in long-term storage at the Military Aircraft Storage and Disposition Center (MASDC) at Davis-Monthan AFB in Arizona, May 1971. USAF
In 1969, the incoming Nixon administration revived the AMSA program with the goal of evolving it into a real strategic bomber. A design by North American Rockwell was chosen over those submitted by Boeing and General Dynamics, and the designation B-1A was assigned. The design of this supersonic bomber included a variable geometry “swing” wing, such as had been used on the F-111 family of fighters and the Grumman F-14 Tomcat fighter, to provide high lift during takeoff and landing, and low drag during the high speeds necessary in combat.
A total of 244 B-1As, including 4 flight-test aircraft, were planned, with the first to enter SAC service by 1979, but the former number was revised downward, as the date was pushed out. The first B-1A flight occurred in December 1974, and an extensive flight test program got underway against the backdrop of growing debate over whether a manned strategic bomber could ever successfully get through Soviet air defenses.