However, unlike an aircraft, the canards were an all-or-nothing proposition, slamming full up or full down with no intermediate position. Fliers and ordnancemen called it a “bang-bang” arrangement—rough but effective. And it happened quickly, multiple times per second. The flipping back and forth of the canards robbed the LGB bomb of kinetic energy in its downward flight—creating more drag than a slick bomb—so it required a fairly high release altitude and a lot of airspeed to give the weapon sufficient energy to reach the target. Too little energy imparted to the weapon when it was released meant that it would literally fall out of the cone—and miss the target. A release below ten thousand feet of altitude was almost pointless. During theater evaluation the Eighth Tactical Fighter Wing began releasing LGBs at twelve thousand feet after a 45-degree dive from twenty thousand.11
The Paveway system required a designator aircraft to lase the target. The original AVQ-9 laser designators were optical telescopes mounted in a Phantom’s rear cockpit, fixed to the left canopy frame and aimed by the backseater, the weapons system officer (WSO). Visually aiming the laser through the optic, he activated the laser beam with a trigger. The gadget, officially called Pave Light, was dubbed the “zot box” after Johnny Hart’s cartoon aardvark that liked to “zot” ants.
Although effective in clear air to ten or twelve miles, the box imposed onerous limits on the designating aircrew. Because the box was fixed to the airframe, the pilot had to fly a pylon turn around the target, presenting the AAA defenders with a predictable flight path. The WSO had to keep the target illuminated by the laser as the bombs fell, so his pilot had to fly a smooth, steady course with no evasive action that would jiggle the WSO’s aim off target. Furthermore, the backseater could not eject with the box in place, requiring precious seconds to remove it before pulling the yellow and black handle.12
Clearly, the in-cockpit box was only a stopgap—the replacement was already on the way: a twelve-hundred-pound Pave Knife designator pod that was carried on one of the designator aircraft’s weapons stations. The gimbaled designator was installed on the lead aircraft in the flight, allowing the Lead to bomb and his wingmen to drop simultaneously. As long as Lead’s WSO kept the designator painting the target with laser light as the pilot maneuvered, all the bombs would take the same airy route to their destination. One pass, four bombs, and it was time to return to base for a beer at the club.
Initially twelve Pave Knife pods were manufactured, with three kept stateside for the test program. Three went to the Navy for specially wired A-6A Intruders. The other six went to Thailand, yet two of those were lost on downed Phantoms. The remaining four were retained for use on high-priority targets only.
Although astoundingly accurate, Paveway had serious operational limitations. It was largely ineffective at night, and laser light could be scattered by smoke, rain, fog, and low clouds, diffusing the clarity of the target dot or causing a false image. Still, the pinpoint accuracy airmen had dreamed about for sixty years was finally achievable… on a clear day. And although clear days in Vietnam were few and far between, they did come around occasionally.
The Paveway project accelerated quickly. Initial flight testing began in April 1965 as a kit on a 750-pound M117 bomb. Field tests began in Vietnam in 1968, but opportunities were limited by Lyndon Johnson’s bombing halt that spring.
Nonetheless, that year an in-theater survey concluded that fighter-bombers armed with LGBs could destroy more than twenty times as many targets for the same number of jets dropping six M117s each. Despite the added laser-incurred expense, there was a huge difference in cost per target destroyed not only because fewer weapons were required but also because attacking aircraft suffered far fewer losses. Cost-benefit analysis… McNamara’s Whiz Kids must have loved that report.
The Air Force already had another precision weapon, Rockwell’s Homing Bombing System, or HOBOS. Like the Walleye ineffectively used against the Thanh Hoa Bridge in 1967, it was an electro-optical weapon, yet it had far more punch because it was mated to a Mark 84 two-thousand-pound bomb. HOBOS had the advantage of also being a “fire and forget” weapon—once the TV seeker was locked onto the target, the firing aircraft was free to maneuver and escape the target area. Deployed to Vietnam in 1969, it proved generally effective, even though it needed a high-contrast target and required modifications to the carrying aircraft. There was also the cost. A HOBOS kit cost more than $20,000 in 1972 dollars versus a Paveway I guidance kit, which cost $2,700.13
Anticipating increased need if the war resumed Up North, in 1971 the Air Force authorized production of Paveway guidance pods at a rate of 920 per month, nearly half for Mark 84 bombs. Seeker kits were one thing, however, and the Pave Knife targeting pods were quite another. By April 1972, when North Vietnam launched the Easter Offensive, the large-scale invasion of the south, the new Pave Knife pods were still scarce.14
The laser-guided bomb systems were soon put to use. From February 1972 to February 1973 some 10,600 LGBs were dropped in Southeast Asia, more than 90 percent being Mark 84 one-ton bombs. In medium-packed soil a Mark 84 left an impressive calling card: a crater thirteen feet deep and forty feet in diameter. LGBs were credited with a combat CEP of less than twenty-five feet, with 48 percent direct hits, and an 85 percent reliability rate. On a clear day an LGB seemed like the finger of God flicking down to smite the enemy.15
“We used to say we were dropping a Cadillac,” Colonel Dean Failor recalled. “They were very accurate, and I guess compared to other munitions of the time [they were] cheap, but to us ‘crew dogs’ they were Cadillacs. They were worth a Cadillac, too, because they worked. We really didn’t like the electro-optical guided bombs because they didn’t always work.”
Failor described the Paveway/Pave Knife accuracy: “We took a bridge out with laser illumination. The first bomb hit the bridge, the second hit the abutment and blew that end off the bridge, the third bomb hit the middle and dropped that span in the river, and the fourth bomb hit the abutment on the other end and blew that up. When we left there was nothing but ripples in the water.”
Describing pilot-WSO coordination, Failor explained, “You had to be good at what you were doing. There had to be cooperation between the guy in back and the pilot and a general understanding of how the bomb worked. Once you got that down though, it went well. When you used it properly the laser-guided bomb was so much better than a regular iron bomb that there was just no comparison.”16
Paveways were truly precision weapons. Failor recalled pinwheeling a bulldozer along the Ho Chi Minh Trail in Laos. It had been stashed in a bomb crater, presenting a difficult angle to an attacker. One LGB destroyed it.17
Paveway I was a rousing success. Texas Instruments had designed, tested, and deployed the system in an astonishingly short time, and it was extremely accurate. Combat CEPs were as little as eight feet.
To put that number in proper perspective, most “iron bombs” had a built-in error of six mils, or twenty inches of dispersion from the aim point for every thousand feet of fall. Imperfect casings and nonuniform explosive content, plus dents and dings in the bomb fins, accounted for that. An unguided dumb bomb was not a rotating sniper bullet. So the most perfectly aimed dumb bomb released in a no-wind environment from a slant range of 9,000 feet could miss the target by 15 feet. With five hundred pounds of high explosive on a medium-hard target that was as good as a direct hit. Yet half the dumb bombs missed by more than 450 feet.
The bad news was that the Paveway had completed its combat evaluation in August 1968, well after Lyndon Johnson’s ban on bombing north of the 19th parallel that year. His subsequent prohibition on attacks anywhere in the North left Paveway all dressed up with nowhere to go. There simply were not enough worthwhile LGB targets in South Vietnam or Laos.
But that changed overnight when General Giap led his NVA army across the DMZ on March 29, 1972, the Easter Offensive.
In the years of the Johnson bombing halt, the Vietnamese, probably with the help of Chinese const
ruction crews, had worked continuously to keep the vital bridge across the Song Ma open while repairing bomb damage. Between 1968 and 1972 eight concrete piers reinforced the approaches for greater resistance to explosives. The span itself still featured a one-meter-gauge railway along the twelve-foot center, with twenty-two-foot concrete roadways supported by cantilever structures on both sides. By the spring of 1972 the Dragon’s Jaw was renewed, refreshed, and well defended. It was as if the innumerable attacks from 1965 to 1968 had not occurred.18
With the Easter Offensive going full blast, another round with the Dragon was inevitable. Some veteran fliers were reflective about the Dragon’s Jaw. One Constellation Phantom pilot recalled, “We thought of calling Hanoi and saying we’d push three A-4s overboard if they would just blow up that damn bridge.”19
CHAPTER 18
BACK TO NORTH VIETNAM
Washington’s immediate response to the North Vietnamese Easter Offensive invasion of South Vietnam was Operation Freedom Train, initially with heavy naval aviation support. Subsequently, when President Nixon approved wider air attacks in early May, Freedom Train morphed into Linebacker, which targeted all of North Vietnam.
Much had changed since the end of Rolling Thunder in later 1968. From 1969 through 1971 US troop strength in Southeast Asia had dropped from over a half a million men to 156,000. By then an additional 20,367 US servicemen had died in theater, although the 1971 toll of 2,414 was the lowest since 1966. The Nixon administration was pulling Americans out of Vietnam just as quickly as it could be safely done—or even faster.1
Many of the combat units still in country were advisers to the Army of the Republic of Vietnam (ARVN) and the Vietnamese Marine Corps. The North Vietnamese conventional invasion in the spring of 1972, with 150,000 men in three striking columns, spearheaded by tanks and backed by artillery, meant that American and South Vietnamese defenders were badly outnumbered at the points of contact.
Despite the NVA buildup in the DMZ and southern North Vietnam, the American military leadership in South Vietnam was caught with its pants down. For several days the US military command in Saigon refused to believe that a major attack was in progress. As usual during the monsoon, low ceilings prevented help from American tactical airpower.
James H. Webb Jr. summarized, “In five historic days combat bases were overrun and abandoned, South Vietnamese units ceased to exist, the largest bridge in the northern part of South Vietnam was destroyed against higher orders in order to stop a tank assault, and B-52s were diverted seconds before they erroneously bombed the besieged US advisers. And, most importantly, despite the chaos the South Vietnamese not only stopped the attack, but were able to counterattack a short time later.”2
It was a stunning military victory for the South Vietnamese and their American allies, yet political support for the war in the United States had eroded too badly for the American government to change its direction, even if it had had the will. The Johnson administration’s lies, obfuscation, irresolution, and incompetence had come home to roost. Nixon and Kissinger were working for some kind of political solution to protect the South Vietnamese from the Communists, but the writing was on the wall: the hard, cold, brutal fact was that with or without a political resolution, the United States was leaving.
The 432nd Tactical Reconnaissance Wing was one of those deployed with Paveways. Possibly the most junior flier at Udorn was First Lieutenant Ron Rowen, a distinguished pilot graduate of flight training the previous August, with a wife and twin boys back in Utah.
He related,
As I was returning from an early-morning mission, I was met by Major Ivy McCoy on the flight line. He asked if I had experience dropping LGBs at Nellis.
The answer was no, but before I could get it out he said, “Say yes.” Then he told me that there was an imaginary basket of delivery parameters that was wide at altitude but narrowed close to the ground. He told me that if I dived directly over the target straight down in afterburner from at least eighteen thousand feet that the “Zot” would designate the target and call ready, ready, pickle at the appropriate time in my dive. Ivy mentioned that I could expect asymmetric flight characteristics if I delivered one of the two bombs being loaded on the plane, then the other on another pass.
With that flight-line brief, my WSO and I manned up and launched. Unfortunately, when we got to what was supposed to be the rendezvous point and were in contact with the OV-10 “Nail FAC” configured with a laser designator, we couldn’t find the guy visually. Lead put me opposite him in a wheel pattern so we could both scan. After two or three trips around the circuit, I spotted a glint several miles north and low. I asked our FAC to reverse his turn and saw another glint, so I confirmed a tally-ho. Lead told me not to lose sight of the FAC. As I came around the turn to the north I was forced to roll out and proceed north to keep the Nail in sight. After two or three minutes I had joined with the FAC, but my lead was still circling “no joy” to the south.
The Nail pilot suggested that I go ahead and hit the target while Lead was trying to find us. Having never before delivered a bomb in a 90-degree dive going Mach 1 with afterburners cooking, the sight of Mother Earth straight ahead as I roared downward was unsettling. Several thousand feet went by very quickly, and the Nail FAC seemed like he had a slow southern drawl, “R-e-a-d-y… r-e-a-d-y… r-e-a-d-y… Pickle!”
On the pullout I pulled five or six Gs instead of the customary four as Vietnam rushed up at me, which seemed judicious, and I was surprised. No asymmetrical loading! On my way back upstairs I realized that I had pickled both bombs. The F-4E switchology was slightly different from the F-4D I was accustomed to flying. Select all stations and bombs singly in the E-model, and you get one bomb off all stations. Select bombs single and all stations on the D-model, and you got one bomb off one station, sequencing from station to station on subsequent pickles.
Needless to say, smoke and dust from those two-thousand-pounders went several thousand feet high, and the hapless bridge target was vaporized. My flight lead had no problem finding where we were and soon joined the party.
The two of us RTB’d [returned to base]. The debrief with bomb damage assessment was curt and abrupt. “Rowen, I should court-martial you for leaving the flight! However, Sierra Hotel BDA! Nothing further needs to be said about this!”
So there you go. No formal training, no formal briefing, just a verbal description of what needed to take place and that was it.
Ron Rowen’s tenure in Thailand was hectic: he flew ninety-one missions, mostly nocturnal, in 181 days.3
The Navy was deeply involved in the wide renewal of air attacks north of the 20th parallel. At the time of the Easter Offensive USS Hancock and USS Coral Sea manned Yankee Station off North Vietnam; USS Constellation and USS Kitty Hawk soon joined them. The four carrier air wings brought some 250 aircraft to the fight.
Meanwhile Air Force reinforcements were inbound from the States. Beginning in early April Operation Constant Guard launched two squadrons totaling thirty-six F-4s from Seymour Johnson AFB, North Carolina, to Ubon, Thailand. They were accompanied by four EB-66 Destroyers from Shaw Air Force Base in South Carolina. A dozen F-105G Wild Weasels accompanied the group and landed at Korat. The planes were in Thailand by April 15.
The next day two more squadrons of Phantoms from Eglin and Homestead Air Force Bases in Florida launched to fly the Pacific to Udorn, Thailand.
Constant Guard III was the largest movement of tactical air command aircraft: 72 F-4Ds from Holloman Air Force Base in New Mexico, with three thousand men and sixteen hundred tons of equipment and supplies.4
The ensuing campaign lasted nearly six months. By whatever name, the renewed air campaign demonstrated America’s global strength. She was a creature of the sea and sky, bringing firepower to bear in numbers and capability unmatched anywhere on the planet.
Among the major players in the renewed air campaign was an old-timer: the Eighth Tactical Fighter Wing at Ubon, Thailand. Inheriting the mantle from the legend
ary Robin Olds was Colonel Carl Miller, a forty-two-year-old professional fighter pilot with fifty-seven F-84 missions to his credit in Korea. He had flown a previous Southeast Asia tour with 278 sorties in F-100s during 1966–1967. He became vice commander of the Eighth Wing in September 1971, then assumed command in February 1972. He flew 189 Phantom combat missions, for a total of 467 in Southeast Asia.5
Miller earned his troops’ loyalty. One of his squadron commanders said, “Colonel Miller was a great leader.… He would fall on his sword for his men and women, and we all knew it. If he said Go, we would go, period.”6
The 1972 campaign involved a curious role reversal for the Eighth Wing. Previously the Wolfpack was lauded as the champion MiG killer wing, with 45 percent of Air Force victories through 1968. During Linebacker the Ubon Phantoms prided themselves as the Bridge Busters and were credited with destroying or seriously damaging more than one hundred spans throughout North Vietnam.7
Commanding the wing’s 433rd Tactical Fighter Squadron was Lieutenant Colonel Rick Hilton, an “old head.” A thirty-eight-year-old Oklahoman, he led “Satan’s Angels,” whose squadron history went back to World War II as a top-scoring P-38 squadron. He had already flown one combat tour by the spring of 1972. Hilton said, “I was privileged to command the 433rd and flew with great warriors like J. D. Franks. J. D. was the expert in laser designators… and I believe he would be hard pressed to recall all of the targets he destroyed.
“The squadron employed both the ‘Zot’ [Pave Light] and Pave Knife laser designators in North Vietnam, but the limitations of the Zot made it less desirable in high-threat environments. The Pave Knife pod was more useful but had two shortcomings: the tracking was accomplished by the GIB [Guy in Back] but the rate-aided feature of the pod design was not robust enough to keep up with the need to pull up to avoid the ground and get out of Dodge. The second problem was that we only had six pods and one of them was in Eglin for continued testing. We had the other five units.”8
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