Operation Mikado

Operation Mikado was the code name of a military plan by the United Kingdom to use Special Air Service troops to attack the home base of Argentina's five Etendard strike fighters at Río Grande, Tierra del Fuego during the 1982 Falklands War. The man in charge of the planning was Brigadier Peter de la Billière, then director of the SAS and SBS Group.

The aim of the operation was to destroy the three remaining Exocet missiles which Argentina still had in their possession and the aircraft that carried them, and to kill the pilots in their quarters. To achieve this, Brigadier Peter de la Billière proposed an operation similar to Operation Entebbe, which consisted of landing approximately 55 SAS in two Lockheed C-130 Hercules aircraft directly on the runway at Rio Grande.

According to the plan, the C-130 would be kept on the tarmac with the engines running while the 55 men of B Squadron SAS performed their mission. If the C-130 survived then they would head for the Chilean air base at Punta Arenas. If not, the surviving members of the SAS Squadron and aircrew would travel to the Chilean border, about 50 miles away.

Preliminary reconnaissance
A preliminary reconnaissance mission on Río Grande, code-named "Operation Plum Duff", was launched from HMS Invincible (R05) on the night of 17/18 May, as a prelude to the attack. The operation consisted of transporting a small SAS team to mainland Argentina on a stripped down Royal Navy Westland Sea King Mark IV, who would then march to the Rio Grande air base and proceed to set up an observation post to collect intelligence on the base's defenses.

The mission required that the Sea King helicopter travel a distance close to its operation range, so this would be a one-way mission. Therefore, the aircrew mission consisted of dropping the SAS team in Argentina, heading to Chile and disposing of the aircraft by sinking it in deep water.

The aircraft, with a three-man crew and nine-man SAS team, launched off the HMS Invincible at 0015 hrs on 18 May. Due to an unexpected encounter with a drilling rig in an offshore gas field it was forced to detour, adding twenty minutes to the transit. As it approached the Argentinian coast after four hours, fog reduced flying visibility to less than a mile. As they approached seven miles from their destination for SAS dropofff, visibility was reduced to such an extent that the pilot was forced to land. The pilot and the commander of the SAS force disagreed as to their exact position, so the SAS commander aborted the mission. The pilots were forced to fly on instruments through Instrument Meteorological Conditions over a nearby mountain range and into neutral Chile. The SAS team was dropped off on the south coast of Inutil Baie where they were to attempt to move to their Observation Post on foot. The helicopter crew flew to a beach closer to Punta Arenas where they landed. One of the two pilots and the aircrewman disembarked on the beach. They cut holes in the helicopter to allow it to sink once it was ditched. The other pilot then flew it out over the water but was unable to sink it. He flew back to the beach in order to cut more holes, but was blinded in his Night Vision Goggles by a blinking "Low Fuel" light and crashed on the beach. The crew set fire to the helicopter and detonated explosive charges before leaving the scene. They moved over the course of several nights to a point of observation near Punta Arenas, where they attempted to make contact with the British Embassy. They were discovered and picked up by the Chilean Military while moving through town, and were turned over to British officials.

According to Argentine sources, on the night of 17/18 May, the helicopter was tracked by the radar of the destroyer ARA Bouchard, which sent a message to her sister ship ARA Piedrabuena patrolling on the north, and then to the air base of Río Grande. Members of the Argentine 24th Regiment of Infantry claimed in 2007 that they hit the helicopter with small arms fire amid thick fog south of Rio Gallegos. Meanwhile, the SAS reconnaissance mission was eventually cancelled.

Abandonment
The lack of on-site intelligence meant that the British forces did not have a clear idea of how Rio Grande was defended, nor any guarantees that the Super Etendards or the Exocets would even be there when the operation took place. The British forces also had no information on how the base was organized, and did not know where the Exocets were stored or even where the pilot's mess was.

By this time, Operation Mikado, which was already seen by experienced SAS members to be a suicide mission, was considered to be impossible to pull off, due to the loss of the element of surprise and due to British intelligence discovering that the Argentines enjoyed far better radar coverage than initially expected. As a consequence, the airborne assault plan attracted considerable hostility from some members of the SAS, which ultimately led to one sergeant submitting his resignation shortly before the team was due to fly out to Ascension and to the squadron's commander being relieved and replaced by the regiment's second-in-command.

Ultimately, the Thatcher administration acknowledged that there was a strong likelihood that the operation would fail. As an alternative, a plan was devised to infiltrate the SAS into Argentina with the help of the Royal Navy submarine HMS Onyx (S21). The plan consisted of dropping the SAS operatives several miles offshore at night for them to make their way to the coast aboard rubber inflatables. The Argentine Navy claims that the Bouchard had shelled a submarine and a number of inflatable boats while on patrol two miles off Rio Grande, at the position -53.72723°N, -67.7°W, on the evening of 16 May 1982.

The Rio Grande area would be defended by four battalions of Marine Infantry of the Argentine Marine Corps of the Argentine Navy, some of whose officers had been trained in the UK by the SBS years earlier.

Assessment
After the war, Argentine marine commanders admitted that they were expecting some kind of landing by SAS forces, but never expected a Hercules to land directly on their runways, although they would have pursued British forces even into Chilean territory in case of attack. The operation's failure would have been a propaganda disaster for the British forces, and conversely a morale boost for Argentina.