Aviation colleagues of Sir Adam Thomson will remember the joke he picked up in America and made his own. ''When there's a recession, you tighten your belt. When there's a depression, you have no belt to tighten. When you lose your pants, you're in the airline business.''

Although competitors on both sides of the Atlantic did lose their financial trousers, Adam Thomson kept his business fully dressed, as it were, over three decades. The story was his way of illustrating how tough the international air transport industry was during the precarious economic climates of the 1960s, 1970s and 1980s.

Adam Thomson achieved international recognition as founder and Chairman of the former British Caledonian Airways, the UK's private enterprise flag carrier which brought new standards of style and innovation to air travellers.

He was born on July 7, 1926, in Clarkston Road, Cathcart, into the family of Frank Thomson, an engine driver with the old London, Midland and Scottish Railway; his wife, Jemima, a shopkeeper; and their two-year old daughter, Evelyn.

After primary education at McDonald's School, he went to Rutherglen Academy and there his interest in aviation was kindled, through membership of the war-time Air Training Corps. In 1943, he went to Coatbridge Technical College to pursue engineering qualifications; and was awarded a Carnegie Bursary at Glasgow Royal Technical College. Eager to serve the war effort as a pilot, he was accepted for training by the Fleet Air Arm of the Royal Navy and joined the Glasgow University Naval Division. Thomson's training as a pilot took place in Canada during 1944. To his regret, qualification came too late for active service. Return from North America saw a number of UK postings, including one spell at Royal Naval Air Station Abbotsinch, later Glasgow Airport. During the Victory day celebrations in London in 1946, he met Dawn Burt, a nurse. They married on July 17, 1948.

Demobilised in March, 1947, with a ''#35 and a pork pie hat'', Thomson sought work as a civilian pilot. For a while he entertained holiday-makers with joy rides and stunt flying on the Isle of Wight.

He went on to fly for a number of airlines, including British European Airways, West African Airways, and Britavia but the idea of creating his own company never left his mind. The opportunity came when Britavia rejected his idea to operate charter flights across the Atlantic. The result was the creation of Caledonian Airways (Prestwick) Limited, with colleagues from Britavia and Jerseyman John de la Haye. Initial working capital was just #54,000. Thomson was chairman and chief pilot; de la Haye was managing director. Caledonian Airways was presented as a distinctly Scottish airline. Its first - and for a while, only - aircraft was a Douglas DC-7C, leased from the Belgian airline, Sabena. With the Scottish Lion rampant on the tail and its cabin crew dressed in the Ancient Black Watch tartan, the aircraft was named Star O' Robbie Burns. It was a tricky time; six UK independent airlines went

out of business in 1961.

The airline's first commercial flight was a charter between Bridgetown and Gatwick, bringing immigrant workers to the UK on behalf of London Transport. Its next trans-Atlantic flight carried a group from the St Margaret's Guild of Scotland to New York. The round-trip charter seat rate was #40.

Caledonian developed as an all-round charter airline, operating intercontinental services and European holiday flights. The fleet developed and by 1970, the airline was carrying 750,000 passengers a year, with a turnover of almost #17m. Above all, it was profitable.

By this time. Thomson had stepped on to a far bigger stage and into national prominence. In the late 1960s, the Labour Government set up a committee of inquiry into civil aviation, under the late professor Sir Ronald Edwards. Its task was to produce a policy for the economic regulation of the industry. The Edwards report made two key recommendations; that the two state corporations, BOAC and BEA be merged; and that a ''second force'' scheduled service airline be created in the independent sector to act as a competitive spur to the nationalised airline. It proposed that this ''second force'' could be formed by the amalgamation of Caledonian Airways and British United Airways (BUA). Thomson and his team seized the moment. There was, however, a major hurdle - BUA had already agreed to a takeover proposal from BOAC. If the dream of owning and running a major international scheduled airline was

to become reality, this deal had to be undone. An unprecedented period of Ministerial and parliamentary lobbying took place. Thomson's tenacity won through and in early 1970, the President of the Board of Trade, Roy Mason, told the House of Commons that the BOAC plan was to be put on ice for negotiations between Thomson and the owners of BUA to proceed. They were successfully concluded in October, 1970, with a #7m takeover deal. The merged company would have a staff of almost 5,000 people and be bigger, in terms of passenger numbers, than some national carriers.

Inheriting Caledonian's Scottish identity, the new airline, to be based at Gatwick Airport, was named British Caledonian Airways (BCAL) and went on to become a major force in national and international air transport. As Chairman and Managing Director and later, Chairman, Thomson steered the airline through the recessionary periods of the early 1970s and the early 1980s to develop the BCAL network and aircraft fleet. He travelled constantly to Africa, South America, North America and Asia in the interests of building the airline. He won great loyalty and commitment from staff around the world who responded to the Thomson spirit of enterprise and endeavour. He was at ease with Heads of State and other leading figures, but his great joy was to get together over a drink, or two, with airline people in every part of the network.

BCAL was, however, to become a victim of the politics which created it. The independent ''second force'', constrained as to where and how it could compete, was fine in a closely-regulated environment. With the advent in 1979 of free-market policies from the new Conservative Government, notably the privatisation of British Airways, many times bigger than BCAL, things would be different. Thomson saw clearly what was coming and mounted a second great political campaign. This resulted in a revised airline competition policy proposal from the Civil Aviation Authority in 1984. It proposed a significant transfer of routes from BA to BCAL in an attempt to redress the competitive imbalance, before the state airline was privatised. BA, by now preparing to go the stock

market under its Government-appointed chairman, Lord King, was furious. Another political battle ensued, this one more ferocious than before. In the end, a small route transfer compromise was agreed and BA was successfully privatised in 1987. During the heat of the debate, Thomson had told the politicians that the Government had three options: to accept the CAA proposals for restructure; to allow BCAL to move from Gatwick to Heathrow to benefit from the far bigger market there; or if those two were not possible, to merge BA and BCAL and form one major airline for Britain. In the end, the third option occurred. Despite a spirited attempt by Thomson to achieve a deal with Scandinavian Airlines System to keep BCAL intact, BA acquired the airline December, 1987 for #250m.

Over three decades, Adam Thomson became a leading figure in international aviation and played a significant part in creating the shape and scope of Britain's contemporary air transport industry. He was knighted in 1983.

Sir Adam Thomson died on May 25 and is survived by his wife, Dawn, and their two sons.

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