Bristol. From powering the world’s only supersonic airliner to enter service to today’s most successful large aero engine family, we examine two of the highest-achieving aero engines of the past 100 years.

Jet power clearly defined the future for aviation in the post-war 1940s as ambitious plans and proposals for new designs of jet engines and aircraft began to emerge in industrialised nations worldwide, with the UK and US at the forefront.

But one major UK engine manufacturer lagged far behind its domestic and global competitors in this race for the future. By the end of 1946 the engine division of the Bristol Aeroplane Company, a powerhouse of production in wartime that supplied tens of thousands of military aero engines, had gained a total of just ten hours of jet engine running experience.

Arch rivals such as Rolls-Royce had already logged thousands.

But from this tiniest of beginnings arose a radical new design that would go on to become a world leader for decades to come – the Olympus.

Bristol lacked jet experience and its project office comprised just three staff, but this is where true innovation blossomed. Charles Marchant, Sam Robinson and Gordon Lewis, tasked by Bristol’s chief engineer to create a large jet engine for a proposed future long -range bomber, shaped a design that used two rotating spools on concentric shafts, each spool able to rotate independently at optimum speed.

After a slow start to development, the arrival at Bristol (from rival Rolls-Royce) of a mathematician whose name features frequently in the story of UK aero engines, Dr (later Sir) Stanley Hooker, soon energised progress. Appointed chief engineer in 1950, he quickly realised the potential of the world’s first two-spool engine and reshaped the company’s engineering effort to gain full advantage. Hooker himself controlled the test-cell for the first Olympus run, confidently and successfully slamming the throttle to full 10,000 lb power after just a few minutes running.

Once a back -marker in the high-stakes race for superior jet power, Bristol now became the leader, with the highest power turbojet on the market. Flight trials began in a converted English Electric Canberra, exploring the engine’s suitability for use in the UK’s high-altitude, high-speed “V-bombers”. These tests proved highly successful and gained worldwide publicity by setting a new world altitude record of 19,406 m (63,668 ft) in May 1953.

The Olympus entered service in the RAF’s Avro Vulcan in May 1956 but was already fighting to keep its place in the improved Mark 2 Vulcan which would be built in much greater numbers. Rolls-Royce was pushing its Conway turbofan which had already been chosen for the Victor Mk 2. But by bravely pledging to match Rolls’ promised price with the new 200- series Olympus, Bristol won the day and ensured the engine’s future.

The Vulcan Mk 2 served the UK in front -line duty until the early 1980s, even taking part in the Falkland’s conflict.

This platform allowed the launch of the successful naval and industrial versions of the Olympus, but it was the final aircraft power plant that would secure the engine’s fame. In 1959 a new, supersonic, Olympus variant had been selected for the RAF’s future tactical strike aircraft, the TSR2. Cost overruns caused cancellation of this very ambitious aircraft soon after it first flew in 1964, but by then its engine had been chosen as the basis of the new power plant for the Anglo -French SST project – the Concorde.

This survived several cancellation attempts and flew in March 1969, some three years after the merger between Bristol and Rolls- Royce. Despite controversy it entered service in January 1976 with Sir Stanley Hooker an enthralled passenger on British Airways’ inaugural flight.

In its ultimate form as the world’s most powerful turbojet, producing more than 38,000 lb of thrust with reheat, the Olympus 593 powered the world’s only successful supersonic transport until Concorde’s retirement in October 2003.

By now, however, the aviation world had changed. Powerful commercial and environmental pressures had forced aviation to clean-up its act. To survive, engine manufacturers had needed to develop far quieter and more fuel-efficient products. Rolls -Royce had pioneered the turbofan and by the 1970s was achieving commercial success with its RB211 family of engines, many of which remain profitably in service today.

But even by 1987, the Rolls -Royce percentage share of the large civil turbofan market remained stubbornly stuck in single-digit figures. Proposed new commercial transports included twin-engine types such as the Boeing 777 and the Airbus A330, requiring unprecedented levels of engine power well beyond the reach of the RB211 family.

It was time for another brave pledge. Rolls- Royce decided that to survive and prosper in this tough competitive arena it would offer engines for every large civil airliner – a family of engines, based on a common core. The three-shaft concept, proven by the RB211, enabled all three prime engine elements (high-, intermediate-and low-pressure systems) to be scaled individually, tuned and tailored to match specific aircraft requirements. One family, so one name: the Trent.

This new family’s first taste of success came in April 1989 when Cathay Pacific became the first airline to specify Rolls- Royce power on an Airbus aircraft, ordering ten Trent 700-powered A330s. Trans World Airlines soon followed, ordering 20 A330s, and more customers began to join the queue. A Trent 700 first ran in August 1990 and the Trent era dawned in March 1995, when Cathay Pacific launched Trent-powered A330 services.

The family soon began to grow. The more powerful Trent 800, for the Boeing 777, first ran in September 1993 and entered service (again with Cathay Pacific) less than three years later. By 1996 Airbus had progressed definition of its new super-jumbo enough for Rolls-Royce to be able to begin development of the next Trent version, the 900, which gained FAA certification on the A380 in December 2006.

Progress continued apace, with the Trent 500 winning sole place on the two long-range versions of the four-engine Airbus A340 transport in 1997, entering service in July 2002. Trent 1000 followed, chosen by Boeing as the launch engine for its advanced new 787 Dreamliner. It was Rolls-Royce and the Trent 1000 that powered it into service in September 2011.

And to bring history right up to date, today the latest family member – the Trent XWB – is about to enter service in another advanced and strong-selling twin, the Airbus A350 XWB. Next will come the Trent 7000, chosen as the sole power plant for future A330neo aircraft and due to run in 2015. It is the most successful large aero engine family in history.

Since its late-1980s inception the Trent has exceeded even the most optimistic contemporary commercial forecasts. Each member of the family has been either the market leader, aircraft launch engine, or both. Trent has become the engine of choice for most new widebody aircraft and today Rolls-Royce is a global driver in this sector.

Although from very different eras, the Olympus and Trent families have more than just aviation success as common factors. Both have also proved ideal for use in industrial and marine markets and have achieved considerable success on land and at sea worldwide, with many marine and industrial Olympus still at work today, nearly 70 years since those three Bristol engineers sat down to draft the engine’s pioneering layout. With that sort of heritage behind it, the Trent family is set to continue delivering engineering excellence at sea, on land and in the air for at least as many decades to come.