Early flight pioneersThe Jet EngineFuture aviation Cars - a failure?Automobiles - The future? Air Travel The Future of Aviation Demand for air travel is expected to triple over the next 20 years. The skies over major cities are already crowded. One solution is to make bigger planes. Nasa's Orbital X-34 reusable rocketplane Airbus Industrie, the pan European aircraft manufacturers who are now second only to Boeing are developing the A3 XX Jumbo Airbus at a cost of £5 billion - though it will probably end up costing European taxpayers double that. Powered by four engines it is the air equivalent of a double decker bus, capable of transporting 1,000 passengers, in four aisles, on two levels. The first A3 XXs are expected to be in service by 2003 but will only have capacity for 555 passengers. Bigger planes will solve a short term problem but not a long term one. Crowded airports will become even more crowded when aircraft start disgorging a thousand tired, grumpy passengers at a time. Romantics dream of using airships for short haul travel but the century’s psyche was so marked by the Hindenburg disaster that Zeppelins have too much bad PR to make up. Between 20-40,000 feet the skies are getting rather full but above that only Concorde, military aircraft and Space Shuttles venture. The cost is getting the machine up high, once there it covers distances in no time at all. Concorde’s problem is that it doesn't fly high enough - as well as being noisy with high fuel consumption. HTOL (Horizontal Take Off and Landing) aircraft are like the Space Shuttle in that they shoot straight up into the atmosphere but are completely reusable. They land like a conventional jet. The future of transcontinental long haul flight has to be in the upper regions of the atmosphere. Skimming the stratosphere will cut travel times to Australia to some two hours. Around 150 years ago the only means of circumnavigating the globe was by a wooden sailing ship. Such speeds will have an even more profound effect on the way we live, on where we live. Since the opening of the Channel Tunnel it has become practical to live in France and work in London - the commuting time less than it would be if one lived in Bournemouth. Global commuting will become even more viable - though the jet lag implications are horrendous - for the rich. The VentureStar is the planned replacement for the Space Shuttle. It is a single stage to orbit (SSTO) vehicle which does not drop fuel tanks and rocket boosters along the way. Between flights it simply requires inspection, refuelling and reloading. Its manufacturers claim it will offer space transportation services at one tenth of today’s cost. The prototype X-33 half the size, is expected to start sub-orbital test flights next summer. The VentureStar is planning to make its maiden flight in 2004 and start commercial operations soon afterwards. The first spaceport sites should be announced later this year. It is not, the designers Lockheed stress, a space ship capable of reaching the moon or other planets It is built for low orbit work transportation of satellites and materials - perhaps to a space station where larger interplanetary craft could be constructed free of the restraints of gravity. So what of man’s final frontier - space. Thirty years have passed since the moon landing and it sometime feels as if we have lost interest in boldly going where no man has gone before. The technology available for space exploration is currently better designed for machine probes than human beings. The distances are too vast and our current vehicles too slow There are fanciful plans drawn up for lunar hotels but long weekends relaxing on the Sea of Tranquillity are a long way away. The human race is one major leap away from practical space travel.