The Special Air  Service or SAS is a  special forces regiment of the British Army that has served as a model for the  special forces of many other countries all over the world. The Special Air  Service together with the Special Boat Service (SBS), Special Reconnaissance  Regiment (SRR), and the Special Forces Support Group (SFSG) form the United  Kingdom Special Forces under the command of the Director Special Forces.
       While the Special Air Service traces its origins to 1941  and the Second World War, they gained fame and recognition worldwide after  successfully assaulting the Iranian Embassy in London and rescuing hostages  during the 1980 Iranian Embassy Siege, lifting the regiment from obscurity  outside the military establishment. 
       The Special Air Service comprises 22 Special Air Service  Regiment of the Regular Army, 21 Special Air Service Regiment and 23 Special  Air Service Regiment provided by the Territorial Army. The three regiments'  tasks are special operations in wartime and primarily counter-terrorism in peacetime.
       The Special Air Service was a unit of the British Army  during the Second World War, formed in July 1941 by David Stirling and  originally called "L" Detachment, Special Air Service Brigade —  the "L"designation and Air Service name being a tie-in to a British  disinformation campaign, trying to deceive the Axis into thinking there was a  paratrooper regiment with numerous units operating in the area (the real SAS  would 'prove' to the Axis that the fake one existed). It was conceived as a  commando force to operate behind enemy lines in the North African Campaign[ and initially consisted of five officers  and 60 other ranks. Their first mission, in November 1941, was a parachute drop  in support of the Operation Crusader offensive. Unfortunately, because of enemy  resistance and adverse weather conditions, the mission was a disaster: 22 men,  a third of the unit, were killed or captured. Their second mission was a  success: transported by the Long Range Desert Group, they attacked three  airfields in Libya, destroying 60 aircraft without loss. In September 1942 they  were renamed 1st SAS, consisting at that time of four British squadrons, one  Free French, one Greek, and the Folboat Section. 
       In January 1943, Stirling was captured in Tunisia and  Paddy Mayne replaced him as commander. In April 1943, the 1st SAS was  reorganised into the Special Raiding Squadron under Mayne's command and the  Special Boat Squadron was placed under the command of George Jellico. The  Special Raiding Squadron fought in Sicily and Italy along with the 2nd SAS,  which had been formed in North Africa in 1943 in part by the re-naming of the  Small Scale Raiding Force. The Special Boat Squadron fought in the Aegean  Islands and Dodecanese until the end of the war. In 1944 the SAS Brigade was  formed from the British 1st and 2nd SAS, the French 3rd and 4th SAS and the  Belgian 5th SAS. They were tasked with parachute operations behind the German  lines in France and carried out operations supporting the Allied advance  through Belgium, the Netherlands, and eventually into Germany. 
       At the end of the war the  British Government saw no further need for the force and disbanded it on 8  October 1945. However, the following year it was decided there was a need for a  long term deep penetration commando unit, and a new SAS regiment was to be  raised as part of the Territorial Army. Ultimately, the Artists Rifles, raised in 1860 and  headquartered at Dukes Road, Euston, took on the SAS mantle as 21st SAS  Regiment (V) on 1 January 1947.
       In 1950, a 21 SAS squadron was raised to fight in the Korean War. After three months of training in England, they  were informed that the squadron would no longer be required in Korea and so  they instead volunteered to fight in the Malayan Emergency. Upon arrival in  Malaya, they came under the command of Mike Calvert who was forming a new unit  called the Malayan Scouts (SAS. Calvert had already formed one squadron from  100 volunteers in the Far East, which became A Squadron — the 21 SAS squadron  then became B Squadron; and after a recruitment visit to Rhodesia by Calvert, C  Squadron was formed from 1,000 Rhodesian volunteers. The Rhodesians returned home  after three years service and were replaced by a New Zealand squadron. By this  time, the need for a regular army SAS regiment had been recognised; 22 SAS  Regiment was formally added to the army list in 1952 and has been based at Hereford  since 1960. In 1959 the third regiment, 23 SAS Regiment, was formed by renaming  the Reserve Reconnaissance Unit, which had succeeded MI9 and were experts in escape  and evasion.
                22 SAS  Regiment
              Since serving in Malaya, men from the regular army 22 SAS Regiment have  taken part in covert reconnaissance and surveillance by patrols and some larger  scale raiding missions in Borneo. An operation against communist guerillas  included the Battle of Mirbat in the Oman. They have also taken part in  operations in the Aden Emergency,Northern Ireland, and Gambia. Their Special  projects team assisted the West German counter-terrorism group GSG 9 at Mogadishu.  During the Falklands War D and G squadrons were deployed and participated in  the raid on Pebble Island. Operation Flavius was an anti–terrorist operation in  Gibraltar against the Provisional Irish Republican Army (PIRA). The SAS counter  terrorist wing famously took part in a hostage rescue operation during the Iranian  Embassy Siege in London. They directed NATO aircraft onto Serb positions and hunted war criminals in Bosnia.
       The Gulf War, in which A, B and D squadrons deployed, was the largest  SAS mobilisation since the Second World War, also notable for the failure of  the Bravo Two Zero mission. In Sierra Leone they took part in Operation Barras,  a hostage rescue operation, to extract members of the Royal Irish Regiment. In  the Iraq War, they formed part of Task Force Black and Task Force Knight, with  A Squadron 22 SAS being singled out for exceptional service by General Stanley McChrystal, the American commander of NATO  forces: during a six month tour they carried out 175 combat missions. In 2006  members of the SAS were involved in the rescue of peace activists Norman Kember,  James Loney and Harmeet Singh Sooden. The three men had been held hostage in  Iraq for 118 days during the Christian Peacemaker hostage crisis. Operations  against the Taliban in Afghanistan involved soldiers from 21 and 23 SAS  Regiments. 
              In recent years SAS officers have risen to the highest ranks in the  British Army. General Peter de la Billière was the Commander-in-Chief of the  British forces in the 1990 Gulf War. General Michael Rose became commander of  the United Nations Protection Force in Bosnia in 1994. In 1997 General Charles  Guthrie became Chief of the Defence Staff the head of the British Armed Forces.  Lieutenant-General Cedric Delves was appointed Commander of the Field Army and  Deputy Commander in Chief NATO Regional Headquarters Allied Forces North in  2002–2003.
              Influence on other special forces
              Following the post-war  reconstitution of the Special Air Service, other countries in the Commonwealth recognised their needs for  Special Forces-type units. Australia formed the 1st SAS Company in July 1957,  which became a full regiment the Australian Special Air Service  Regiment (SASR) in August 1964.The New Zealand Special Air Service squadron was formed in 1954 to serve with the British SAS in Malaya.On their return from Malaya, the C (Rhodesian) Squadron formed the basis for  creation of the Rhodesian Special Air Service in  1961.
       Non-commonwealth countries  have also formed units based on the SAS. Impressed by the Australian SASR  methods in Vietnam,  American General William Westmoreland ordered the formation of  a Long Range Reconnaissance Patrol (LRRP) unit in each infantry brigade, modelled on the SASR.Another American unit, Delta Force, was formed by Charles Alvin Beckwith, who served with 22  SAS as an exchange officer, and recognized the need for a  similar type of unit in the United States Army. It is claimed the Israeli Sayeret Matkal was also modelled on the SAS and even  shares the same "who dares wins" motto.The French 1st Marine Infantry Parachute  Regiment can trace its origins to the Second World War 3rd and 4th SAS,  also adopting their "who dares wins" motto.The  portuguese police special forces Grupo de Operações Especiais was also  formed by the SAS. Still today they train together.
      Special Projects Team 
      The special projects team is the official name for the  Special Air Service anti–hijacking counter–terrorism team. They are trained in Close Quarter Battle (CQB) and sniper techniques  and specialize in hostage rescue in buildings or on public transport. The team were formed in 1975 when then Prime Minister Edward  Heath asked the Ministry of Defence to prepare  for any possible terrorist attack similar to the massacre at the 1972 Summer Olympics and ordered that the SAS  Counter Revolutionary Warfare (CRW) wing be raised.
       Once the wing had been established, each squadron rotated  on a continual basis through counter–terrorist training including hostage  rescue, siege breaking, and live firing exercises — it has been reported  that during CRW training each soldier expends as many as 100,000 pistol rounds.  Squadrons refresh their training every 16 months, on average. The CRW wing's  first deployment was during the Balcombe Street Siege. The Metropolitan Police had trapped a PIRA unit; they surrendered when  they heard on the BBC that the SAS were being sent in.
       The first documented action abroad by the CRW wing was  assisting the West German counter-terrorism group GSG 9 at Mogadishu. In 1980 the SAS were involved in a hostage rescue during the Iranian Embassy Siege.
      United Kingdom Special Forces
      The Special Air Service are under the operational command  of the Director Special Forces (DSF), a major-general grade post. Previously ranked as a brigadier, the DSF was promoted from  brigadier to major-general in recognition of the significant expansion of the United Kingdom Special Forces (UKSF). The UKSF originally consisted of the regular and the reserve units of the SAS  and the Special Boat Service, then joined by two new  units: the Special Forces Support Group and the Special Reconnaissance Regiment. They are supported by the 18 (UKSF) Signal Regiment and the Joint Special Forces Aviation Wing,  part of which (8 Flight Army Air Corps) is based in  Hereford with the SAS.
      Recruitment Selection and Training
       All members of the United Kingdom armed forces can be  considered for special forces selection, but historically the majority of candidates have an airborne forces background. All instructors are full members of the Special Air Service Regiment.  Selections are held twice yearly, in summer and winter, in Sennybridge, Powys in the Brecon  Beacons. Selection lasts for five weeks and normally starts with about 200  potential candidates. On arrival candidates first complete a Personal Fitness Test (PFT) and a Combat Fitness Test (CFT). They then march cross country against the clock, increasing the distances  covered each day, culminating in what is known as the Fan dance: a 14 miles (23 km) march with  full equipment scaling and descending Pen y Fan in four hours. By the end of the hill phase candidates must be able to run 4 miles in 30  minutes and swim two miles in 90 minutes.
        Following the hill phase is the jungle phase, taking  place in Belize, Brunei, or Malaysia. Candidates are taught navigation, patrol formation and movement, and jungle  survival skills. Candidates returning to Hereford finish training in battle plans and foreign  weapons and take part in combat survival exercises, the final one being the week-long escape and evasion. Candidates are formed into  patrols and, carrying nothing more than a tin can filled with survival  equipment, are dressed in old Second World War uniforms and told to head for a  point by first light. The final selection test is arguably the most gruelling: resistance to interrogation (RTI),  lasting for 36 hours.
       Typically, 15–20% of candidates make it through the hill  phase selection process. From the approximately 200 candidates, most will drop  out within the first few days, and by the end about 30 will remain. Those who  complete all phases of selection are rewarded with a transfer to an operational  squadron.
        
        Source
      wikipedia.org/
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