Dancing with Death

Development of SEAD Tactics and Technologies in the Air War Against North Vietnam, Part 1

By: G. Wolfe

By July 1965, Operation Rolling Thunder - the sustained aerial bombardment campaign against North Vietnam - had entered its fifth month. Devised by the Commander-in-Chief, Pacific (CINCPAC) Admiral Harry D. Felt in 1964, the operation was designed to stop the flow of men and material towards South Vietnam, persuade the Democratic Republic of Vietnam to cease its support for the communist insurgency in South Vietnam, and bolster the South’s morale. It was conducted by the combined force of USAF, US Navy and the Republic of Vietnam Air Force (RVNAF) until its cancellation on 2 November 1968

On 24 July, four McDonnell Douglas F-4C Phantoms of the 47th TFS, 15th TFW, led by Lt. Col. William A. Alden (Callsign Leopard) and a Douglas EB-66C electronic intelligence (ELINT) aircraft were cruising at 23.000 feet near Lang Chi, west of the North Vietnamese capital of Hanoi. The flight was providing air cover and electronic reconnaissance support for the F-105 strike packages that were hammering the ammunition storage facility at Dien Bien Phu. Earlier, the crew of the EB-66 had picked up a radar signal from a Soviet-made SNR-75 (NATO Reporting Name: Fan Song) Fire control radar - part of S-75 Dvina (NATO Reporting Name: SA-2 Guideline) surface-to-air missile system. At about 0805 local time they again radioed "the bluebells are ringing", a warning that the hostile radar was active and tracking the flight from within North Vietnam. Lt. Col. Alden, Flying on the far left of the Leopard flight, spotted two missile trails fast approaching the formation from their right and below.

But it was too late. Before the flight could react, the first missile exploded underneath Leopard 02 (63-7599) on the opposite side of the formation. Its pilot, Capt. Roscoe H. "Ross" Fobair was killed on impact while his WSO, a former World War II B-17 crewman Capt. Richard P. "Pop" Keirn ejected safely from the stricken aircraft. Capt. Keirn would spend eight years as a Vietnamese prisoner-of-war until he was released on 12 February 1973.

The warning issued by the EB-66C crews at least gave the rest of the Leopard flight precious seconds to evade the second missile, though the three remaining F-4s were peppered by shrapnel from the second missile and limped back to Ubon Royal Thai Air Force Base. The shoot down of Leopard 02 marked the first of many casualties inflicted by surface-to-air missiles (SAM) against USAF and US Navy aircrafts in the Vietnam war. In total, the United States confirmed 206 of their aircrafts lost as the result of North Vietnamese missile batteries, while North Vietnam claimed 1.046 aircrafts shot down by their missiles.

The Threats

The SA-2 Guideline surface-to-air missile system was by no means new at the time of the Vietnam war. It was the same missile that had shot down the U-2 spy plane piloted by Francis Gary Powers over Soviet airspace five years earlier. The system debuted in 1957 as the response to the development of nuclear-capable long-range jet bombers such as the Vickers Valiant, Boeing B-47 Stratojet, and its successor B-52 Stratofortress, it replaced the 130 mm KS-30 and 100 mm KS-19 anti-aircraft gun as primary high-altitude air defense of the Soviet heartland.

The primary element of the SA-2 missile system was the V-750 missile, measuring 10,6 meters in length and weighed around 2.270 kilograms. Boosted by a solid-propellant rocket motor and a liquid-fueled sustainer, it could achieve the terminal velocity of Mach 3 and a maximum engagement range of 29 kilometers. Three of such missiles could be simultaneously guided by an SNR-75 (NATO Reporting Name: Fan Song) Fire control and tracking radar into a single target, which have a tracking range of 60-120 kilometers.

Acting as the eyes and ears of the SA-2 missile battery was the P-12 Yenisei / P-18 Terek (NATO Reporting Name: Spoon Rest A-C / Spoon Rest D) 2D Surveillance and target acquisition radar, which searches the 200-250 kilometers radius around the battery for a target to be tracked by the Fan Song radar. A secondary NRZ-12 (NATO Reporting Name: Score Board) identification-friend-or-foe radar was often used in conjunction with the Spoon Rest radar and, together with PRV-11 (NATO Reporting Name: Side Net) height finder radar, completed the SA-2 missile system.

The SA-2 missile batteries were typically organized into a regimental structure with three subordinate battalions. The regimental headquarters controlled the Spoon Rest surveillance radar and coordinated battalion actions, While each battalion employed a single Fan Song fire control radar and six single-rail launchers positioned 60-100 meters apart in a distinguishable hexagonal 'flower' pattern. While the Fan Song radar could only guide three missiles at a time, it had the track-while-scan capability and therefore three missiles could be launched immediately after the previous three had completed their run.

The downside of the SA-2 missile system was its inability to engage low-flying targets; it has a minimum engagement altitude of 3.000 meters and a minimum engagement range of 7 kilometers. To fill the gap left by SA-2's limitation, North Vietnam fielded a wide variety of anti-aircraft artillery (AAA) ranging from the 12,7 mm DShK machine guns to radar-guided 100 mm KS-19 heavy anti-aircraft guns. The lighter guns of 37 mm caliber and below generally relied on optical sighting and ranging, while heavier guns of 57 mm to 100 mm caliber were guided by SON-9 (NATO Reporting Name: Fire Can) Fire director radar in combination with the PUAZO-6 Fire director. The Fire Can radar was based on the earlier SON-4 design which in turn was based on the American SCR-584 system and was capable of guiding up to eight guns against a single target simultaneously.

Combined with ground-controlled MiG-17 and, later, MiG-21 interceptors, the North Vietnamese air defense network posed a credible threat toward US strike packages that took part in operation Rolling Thunder, even without being entirely composed of state-of-the-art equipment.

The United States was well aware of the buildup of North Vietnamese SAM sites as early as 5 April 1965, when a US Navy RF-8A Crusader reconnaissance plane from aircraft carrier USS Coral Sea photographed five new sites being constructed within the 30 miles restricted zone around Hanoi. The Joint Chief of Staff (JCS) in the Pentagon insisted that the sites must be destroyed before it could be completed, but the Secretary of Defense Robert McNamara, anxious not to provoke Chinese and Soviet involvement, was able to convince president Johnson to keep the SAM sites off limits - which also included missile depots in Hanoi and Soviet ships off-loading cargo at Haiphong harbor.

To counter the threat posed by North Vietnamese SAM sites, USAF deployed six Douglas EB-66C electronic warfare aircrafts to Takhli Royal Thai Air Force Base starting from May 1965. Based on the airframe of the B-66 Destroyer light bomber, The EB-66C was the first aircraft designed from the onset for electronic intelligence (ELINT) missions. It was primarily employed to gather intelligence on enemy radars and provide warning against Fan Song transmissions and operated by an expanded crew of seven, which included the additional electronics warfare specialists.

A dedicated variant fitted with stand-off jamming equipment, the EB-66B, started arriving in theater from October 1965 to replace the aging and less capable EA-1B Skyraider and EF-10B Skyknight in high-threat electronic warfare missions. It offered stronger and broader jamming barrage that covered most frequencies employed by North Vietnamese air defense. Furthermore, the Air force EB-66 were able to refuel from drogue-equipped KC-135 tankers, in contrast to the aforementioned aircrafts which didn't have refueling capability, extending its time on station.

The EB-66B were not without vices though, it was found out that its powerful jamming interferes with its own radar warning equipment, requiring EB-66B to work in tandem with EB-66C to provide SAM warning. Due to the positioning of its ECM antennas, the jamming signal of the EB-66B also did not form a perfectly circular pattern, rather resembling the wing of a butterfly with the strongest signal radiating perpendicular to the flight path. For these reasons, EB-66B were deployed in pairs arranged in such a way that at least one of them is always broadside to enemy radar. These pairs orbited within 24 kilometers range from the target to lay down jamming barrage, while another flight of EB-66C orbited safely beyond the missile engagement range to provide SAM detection and ensured that the jamming barrage covered all the frequencies used by the enemy.

Drawing Blood

As it had been demonstrated by the shoot down of Leopard 02, even the EB-66 escorts were insufficient to completely eliminate the threat posed by the North Vietnamese SAM sites. After the news of the incident had reached Washington, the JCS again urged the Johnson administration to authorize an immediate strike against North Vietnamese SAM sites, which had now been discovered outside the restricted zone. At last, president Johnson gave Operation Spring High the green light. On 27 July, two days after the shoot down, a force of 48 F-105 Thunderchiefs, escorted by 13 F-4C Phantoms, 8 F-104 Starfighters, 3 EB-66Cs and 6 EF-10Bs were mustered to attack the SAM sites located 25 kilometers west of Hanoi.

The Secretary of Defense McNamara, on the other hand, still kept a tight rein on the air war against North Vietnam and insisted that the attack be limited to the two SAM sites that were involved in the shoot down of Leopard 02, on the ground that Soviet ‘advisors’ might be manning the sites and targeting them might incur retaliation from the Soviet Union, possibly escalating the war. Moreover, the scope of the attack was limited to only the missile launchers, radars, and their supporting equipment; none of the Thunderchiefs were assigned to attack the AAA protecting the sites.

Despite having to fight with one hand tied behind their backs, the attackers pressed on. The F-105s of 12th and 357th TFS, flying from Korat Royal Thai Air Force Base, would attack SAM site 6 from the south, while those of 80th and 563rd TFS were flying from Takhli and approached SAM site 7 from the northwest down the Red River Valley. Both flights would refuel from KC-135 tankers before crossing through Laos and drop down to just 100 feet above the North Vietnamese countryside to hide themselves in the ground clutter.

As soon as they entered North Vietnamese airspace, the attack force was greeted by a relentless barrage of anti-aircraft fire of every caliber employed by the communist force. The thick web of fire forced them to descend further down to 50 feet, churning rooster tails of mud and water as their bomb-laden F-105s sped down the rice paddies at Mach 0,65. The Korat force arrived on site first, unleashing a deadly hail of CBU-2 cluster bomblets over site 6 while the BLU-27 napalm canisters rose hell upon men, vehicles, and equipment. As the Korat force egressed out of site 6, the Takhli force zipped past them as they moved in for the attack against site 7. Flying at an extremely low altitude, both formations were forced to pull hard right to avoid colliding with each other at combined speed of over 1.000 knots.

Four F-105s would fall victim to lethal close-range fire from North Vietnamese 23 mm and 37 mm guns. Capt. Kile D. Berg of the 563rd TFS was the first to fall when his F-105 was hit by AAA, turning his aircraft into a ball of fire as he made his attack pass just feet above site 7. Thankfully, his quick reaction saved him and he was able to eject from the burning inferno. His squadron mate, Capt. Walter B. Kosko, was not as fortunate. His aircraft was hit by AAA near site 7 and was able to eject from his burning aircraft. However, neither the US search and rescue team nor the North Vietnamese troop ever found Capt. Kosko or his remains. He was declared killed in action.

Capt. Robert B. "Percy" Purcell and Capt. Frank J. Tullo of the 12th TFS would also fall victim to hostile AAA as they cleaned up leftover targets over site 6. Both pilots were able to eject from their aircraft, though only Cap. Tullo was able to be recovered by the search and rescue team after the mission. In the end, Capt. Berg and Capt. Purcell would spend more than seven years as POW and were awarded the silver star for the day's action.

The tragedy didn't end with the mission. Capt. William J. "Black Bart" Barthelmas of the 357th TFS managed to reach Thailand after his F-105 was severely damaged by AAA over Site 6. However, when his flight lead Major Jack G. Farr was pulling alongside to inspect the damages, Capt. Barthelmas lost control of his F-105 and it pitched up against Major Farr's. Both pilots were killed when the aircraft collided with each other.

What the pilots didn't know at the time was that within two days of planning and going back-and-forth with Washington, the North Vietnamese had removed all of their SAM launchers and equipment from site 6 and 7. In their place, they had set up a painted bundle of bamboo as a decoy and moved in over 130 AA guns in anticipation of a retaliatory strike - The surviving pilots were shocked to learn that Operation Spring High had destroyed two worthless targets at the cost of six Thunderchiefs and five of their comrades killed or captured.

On the night of 11-12 August 1965, just 2 weeks after the fruitless effort by USAF to silence North Vietnamese SAM sites, two US Navy Douglas A-4E Skyhawks from Navy Attack Squadron 23 (VA 23) were again struck by SAM as they were performing nighttime armed reconnaissance mission about 80 kilometers south of Hanoi. The flight leader, LCDR. Francis D. Roberge, and his wingman, LTJG. Donald H. Brown, Jr., observed what appeared to be two flares glowing beneath the clouds 15 miles north of their position. They watched the two spots of light come out of the clouds and move closer and closer. In sudden recognition of danger, both pilots pushed over and added full power. It was too late. Seconds later the SAMs exploded, destroying LTJG. Brown’s A-4 and damaging LCDR. Roberge’s. Although his plane was on fire, the latter managed to limp back and land aboard the Midway,

The Navy responded to the shoot down by launching Operation Iron Hand, adopting the same low-altitude tactics that the USAF had recently used to search and destroy the enemy SAM sites, with equally disastrous results. Between 12 and 13 August, 76 Iron Hand missions searched at low levels for the sites. Five planes and two pilots were lost to AAA, and seven other planes were damaged, but no SAMs were found.

The Failure of Operation Spring High and early Iron Hand missions brought to the United States’ attention the high mobility of North Vietnamese SAM batteries. Even after maintaining an alert force of fighter-bombers, fueled and armed ready to attack newly discovered SAM sites, USAF still relied upon photo reconnaissance to pinpoint the positions of SAM launchers, which took up to 8 hours to process and interpret. By which time, the launchers would have been packed up and moved by truck and van to a new location. Whenever overflown, the SAM batteries always moved immediately, leaving behind several AAA to greet the oncoming strike force.

In an effort to reduce the reaction time needed between detection and the dispatch of a strike force, USAF planners tried to use radio-controlled drones, such as Teledyne-Ryan Lightning Bug, to lure enemy radar into transmitting so that the EB-66Cs and EKA-3Bs could locate its sources. On 31 August 1965, two Lightning Bug drones launched from a specially modified DC-130 control aircraft were able to trigger enemy radar as they approached Hanoi from the Gulf of Tonkin and an EB-66C flight pinpointed the source to an area near the town of Piu Tho, about 65 kilometers northwest of Hanoi, within a 3,2 kilometers accuracy. Four F-105s were dispatched but failed to find any trace of a SAM site, one of the planes was lost to AAA, though the pilot was rescued.

The use of drones did decrease the reaction time. However, it was less precise than aerial photography and the attackers needed to search an area 6,4 kilometers in diameter to pinpoint the exact site, often well camouflaged and heavily defended by AAA. Even if the attack force managed to find the site, the three hours time the F-105s needed to reach the suspected sites is still more than enough for the SAM batteries to pack up and move to a new location. What was needed was an airplane that could lead the fighter-bombers into North Vietnam, detect and locate hostile Fan Song radar, then direct attacks against the SAM batteries before they could relocate.

Back in the Pentagon, the air staff formed the Anti-SAM task force to address the threat posed by North Vietnamese SAM batteries. Headed by Brig. Gen. Kenneth "KC" Dempster, a 48 years old former World War II B-26 pilot, the task force would involve members of USAF, US Navy, and prominent members of US defense contractors to develop countermeasures and tactics against the deadly missiles. In all, 46 recommendations made by the task force were accepted by the Air Force and put into production, ranging from the adoption of ATI Vector RHAW system, QRC-160 self-protection pod, to the much-needed AGM-45 Shrike anti-radiation missile, laying the groundwork for the famous “Wild Weasel” SAM killers projects. The "Iron Hand" missions, named so for the steady hand and nerves of steel it took for pilots to fly directly against the SAM sites, would become synonymous with joint USAF and US Navy SEAD efforts throughout the war.

To be continued on Part 2