Led by Korean War ace Colonel Robinson Risner, it comprised 79 aircraft, including 46 F-105 Thunderchiefs as the main strike force.

Other types were 21 F-100 Super Sabres as AAA suppressors to attack ground-based guns, fourteen F-100s acting as MiG CAP (combat air patrol) and two RF-101C Voodoos to do damage assessment, plus ten KC-135 tanker aircraft.

Armed with three 23mm cannons but no missiles, it was a faster upgraded MiG-15 fitted with an afterburning engine, and a radar-ranging gunsight reverse-engineered from the F-86A (as well as a new, more sharply swept wing to increase its critical Mach number, therefore top speed).

[citation needed] The VPAF had nevertheless demonstrated the ability to engage modern US fighters, and afterwards recognized April 3 as Air Force Day.

This time, eighty planes were engaged, including 48 F-105s, carrying only 750 lb (340 kg) bombs, as the inadequacy of the Bullpup had been fully demonstrated.

During the 4 April 1965 engagement, a force of eight MiG-17s (half flying as decoys) from the 921st "Sao Do" (Red Star) Fighter Regiment (FR) were again given the task of confronting a large group of modern American supersonic fighter-bombers.

These included "Steel", "Iron", "Copper", "Moon", "Carbon", "Zinc", "Argon", "Graphite", "Esso", "Mobil", "Shell", and "Petrol".

The VPAF made ground-based AAA sites the first line of defence, with fighters attacking after ground gunners ceased fire.

Although, on paper, the F-105 was capable of Mach 2+, when loaded with ordnance under its small wings, it was subsonic and unready to tangle with any fighters that might get past the escorts.

Vietnamese flight leader Trần Hanh spotted four F-105Ds at 10:30 starting to drop their bombs, ordering his wingman, Pham Giay, to cover his attack.

[8] He fired at 400 meters, observing one F-105, piloted by Major Frank E. Bennett (355th TFW, KIA) fall in flames into the Gulf of Tonkin.

Magnusson finally bailed out twenty miles away over the Gulf of Tonkin near the island of Hon Me, and was eventually listed as missing and then killed after a 48-hour search.

The fortunate pilot was briefed the day before about this maneuver by Captain John Boyd from Nellis Air Force Base, who would later become a significant voice in the design of America's fighter aircraft.

[11] After the quick success of downing two American fighters, the outnumbered North Vietnamese defenders faced the remaining F-100s and F-105s now fully alerted to their presence and turning their attention to the MiGs.

He and wingman Pham Giay stayed south of the bridge, while Le Minh Huan and Tran Nguyen Nam flew to the north.

The lead F-100 got a locking tone as he fired an IR guided Sidewinder air-to-air missile once he had a clear shot, but it passed above its target, while Connolly and Kilgus engaged with 20mm cannon.

[15] While worrying about the rapidly falling altitude, he opened fire at 7,100 feet, observing puffs and sparks coming off Giay's vertical tail fin before losing visual contact as he pulled up, just barely clearing the water.

Aviation writer Larry Davis also records that Kilgus' wing man also reported a kill, but it was denied by higher headquarters at 7th Air Force.

Low on fuel, he opted to land at the nearby Ke Tam valley, but was detained by the locals until he produced his VPAF badge.

After losing all of their defending fighters and three pilots, in retrospect the action might seem to be a tactical draw, but it was nonetheless celebrated as a "glorious victory over US aircraft to ensure the flow of war supplies to the south".

While the F-105 would finish off its service with a slightly better than even kill-to-loss ratio over MiGs, the large plane had been designed primarily to deliver bombs at low level rather than shoot down other fighters.

This experience would re-introduce the requirement that future fighters would need to be able to mix with MiGs on more equal terms and not just shoot missiles from a distance.

Between 1965 and 1968, until US President Lyndon B. Johnson temporarily called off air raids against North Vietnam, the bridge was a regular objective for navy Alpha strikes.

The plan was to float the mines down the river, till they reached the bridge, where the magnetic sensors would set off the charges, hopefully wrecking it permanently.

The only aircraft with a large enough hold to carry these weapons was the slow-flying C-130 Hercules transport, so the operation was due to take place at night, to reduce its vulnerability.

On 27 April, twelve Phantoms of the 8th Tactical Fighter Wing, based at Ubon, Thailand attacked the Thanh Hóa Bridge.

The raid was carried out without a hitch, and when the dust of the explosions had cleared it became apparent that the bridge had been dislodged from its western abutment, dropping one half into the river.

To complete its destruction, a second attack was scheduled for the thirteenth of May when fourteen Phantoms were engaged, with LGBs of up to 2,000 lb (910 kg) aimed at the central pillar supporting the bridge.

However, the concentration of air defense assets also took its toll on passing aircraft and in total an estimated 104 American pilots were shot down over a 75-square-mile (190 km2) area around the bridge during the war.

[22] In his 1976 essay collection, Mauve Gloves & Madmen, Clutter and Vine, Tom Wolfe recounted a rueful story that circulated among Navy pilots who flew sorties against the Thanh Hóa Bridge.