Final Battle - The Mayaguez Rescue Operation
In the aftermath of the Vietnam War, US forces fought one last battle. This battle took place on May 15, 1975, and concerned the rescue attempt of 39 American sailors from the merchant vessel SS Mayaguez. The SS Mayaguez was on its way from Hong Kong to Sattahip in Thailand, when, on May 12, it was intercepted and seized by the Khmer Rouge Navy. The crew was brought to the mainland, while their ship was anchored off the Island of Koh Tang. The seizure of the SS Mayaguez was seen by the USA as an act of piracy, and the US President, Gerald Ford, demanded the immediate release of the 39 sailors and their vessel by the Khmer Rouge. When this demand appeared to fall on deaf ears, an ad hoc US military force, consisting of US Marines, US Navy and US Air Force units was rapidly assembled to try to rescue the crew.
The rescue attempt ended in disaster, when four helicopters were shot down or disabled by Khmer Rouge forces. The Marines had to withdraw from Koh Tang without finding any of the US sailors. In total, the US rescue force lost 41 killed, which ironically outnumbered the SS Mayaguez crew. The 39 sailors were released shortly afterwards, together with their vessel. Even though the rescue attempt was seen by some as being indicative of the US willingness to use military force before all other efforts, including diplomatic, had been exhausted, it also reestablished faith in the USA as a dependable ally. The rescue operation showed that the USA would go to great lengths to rescue its soldiers and citizens. In doing so, the USA were determined not to let the seizure of the SS Mayaguez turn into another USS Pueblo affair.
After the Khmer Rouge victory on April 17, 1975, a conflict between Cambodia and South Vietnam, and a few weeks later, Vietnam nearly erupted. A 1967 agreement between Cambodia and South Vietnam, concerning some disputed islands, became an issue after the Khmer Rouge victory. In 1939, the French had drawn the Brevie line, a maritime boundary between Cambodia and Vietnam. It is arguable whether the Brevie line could be considered a French colonial administrative boundary or an international border, but nevertheless, after April 17, the Khmer Rouge unilaterally extended their territorial waters, including the disputed Islands which were occupied by. Khmer Rouge forces. In addition, several cargo vessels, including a Panamanian and a Swedish vessel were either fired upon or boarded by the Khmer Rouge Navy. On May 12, a US merchant ship, the SS Mayaguez, on its way from Hong Kong to Sattahip in Thailand with a cargo of paint and other non-lethal materials, was seized by the Khmer Rouge Navy. The SS Mayaguez was boarded after it passed within two miles off the island of Poulo Wai. When the seizure became known in Washington, the US administration made two attempts, via the Chinese embassy, to contact the Cambodian Government. The reason for using Chinese mediators was due to the fact that the USA had no diplomatic relations with the Khmer Rouge. The Chinese returned the first message, saying they had no lines of communication with the Cambodian leaders in Phnom Penh. The second diplomatic attempt failed as well. Apparently, a Chinese diplomatic source claimed that China would not protest if the USA resorted to the use of force.
The US administration had little information about the new Cambodian Government. No diplomatic missions remained in Phnom Penh after the Khmer Rouge take over. In fact, the question of whether a Cambodian Government per se existed or not, and who its leadership were, could not be answered. Several different military options were considered, including massive B-52 strikes on the Cambodian mainland, or limited, pin-point raids performed by tactical carrier-based attack aircraft.
A few hours after the news of its capture, the SS Mayaguez was located by a US Navy P-3 Orion maritime reconnaissance aircraft. The Orion located and photographed the SS Mayaguez anchored off the island of Koh Tang, 40 miles from the Cambodian mainland. There was no sign of the crew. During the reconnaissance mission, the P-3 was hit by fire from Khmer Rouge patrol boats, being lightly damaged.
After the initial diplomatic efforts failed, orders were given to US Pacific Command to assemble a rescue force. This force consisted of 288 Marines from Battalion Landing Teams 2 and 9, as well as 51 USAF Security Police personnel from the 56th SPS. The Marines were brought in from Okinawa and the Philippines, while the USAF security Police unit was based at Nakhon Phanom. Both the Marines and the Security Police were to be transported to Koh Tang in 16 Sikorsky CH-53Cs from the 40th ARRS and 21st SOS, based at Nakhon Phanom in North-Eastern Thailand. The aircraft carrier USS Coral Sea (CVA-43) was also part of the rescue force, as well as several other ships from the US 7th Fleet, including the frigate (FF1074) USS Harold Holt. Aboard the USS Coral Sea were McDonnell Douglas F-4Ns of VF-51 and VF-111, Vought A-7E Corsair II's of VA-22 and VA-94, Grumman A-6A Intruders of VA-95, Vought RF-8G Crusaders of VFP-63 and Grumman E-1E Tracers of VAW-11.
No accurate and up-to-date information on Koh Tang was available. It was believed that between 30 and 40 poorly armed and trained Khmer Rouge soldiers were based on the island. In an effort to cut off Koh Tang from the Cambodian mainland, several Khmer Rouge patrol boats were sunk by US aircraft. The Kampuchean gunboats were first attacked by USAF AC-130 Spectre gunships from the 16th SOS, which attacked several gunboats in the vicinity of the SS Mayaguez. Five of the gunboats were later finished off by USAF A-7D Corsair II's of the 3rd TFS during the early morning of May 14. As a further retaliation, four diversionary air strikes against targets on the Cambodian mainland were ordered by President Ford. It appears though that only two strikes, the second and third, were actually carried out. The first wave of attack aircraft had to await permission to proceed by President Ford, but, due to the lateness in receiving such an order, the aircraft had to drop their ordnance into the sea, and return to the USS Coral Sea. The fourth wave was cancelled, but not by the President himself. The air strikes were directed against Cambodias sole oil refinery at Kompong Som (present day Sihanoukville) and the air base at nearby Ream. At Ream, 17 out of 20 T-28 Trojans were reportedly destroyed at around 0845 during the morning of May 15 by A-7Es and A-6As from the USS Coral Sea, thereby eliminating any risk of aerial opposition. Naval facilities were also attacked. However, post-strike reconnaissance photos showed that the number of T-28D's destroyed during the raid on Ream were in fact far lower than 17. Apparently, only 12 T-28s were based a Ream, with five of them being confirmed as destroyed.
On May 13, at 2030 local time, 16 Sikorsky CH-53Cs took off from RTAFB Nakhon Phanom. Shortly after take off, one of the helicopters, s/n 68-10933 from the 21st SOS, 56th SPS, fell out of formation, crashed and exploded on impact. All 23 aboard, including four crew, 18 USAF security police and one linguist, were killed in the crash. Other CH-53s landed nearby, but exploding ammunition and burning fuel hindered all rescue attempts. The CH-53 crashed in the Phannanikhom District, 35 miles west of Nakhon Phanom. Officially, the CH-53C was on a routine training mission, but all 23 killed in the crash were awarded the Bronze Star posthumously.
To this day, the cause of the crash has not been established with certainty. According to some sources, the crash was due to a technical malfunction. One source claims that one of the main rotorblades separated from the rotorhead, while others claim that the crash was due to enemy action. The whole truth about the crash may never be known. The crash caused a major rift between the Marines and the USAF Security Police. According to an article in the Bangkok Post, published a few days after the rescue attempt, the "Disagreements between Marines and Air Force security forces became heated almost to the point of violence." The remaining Security Police wanted to be the ones rescuing the crew of the SS Mayaguez taking a bloody revenge on the Khmer Rouge. The remaining CH-53s continued to U-Tapao, from where the various elements of the rescue operation were being co-ordinated.