The head of the UK's aviation regulator has warned against 'divergent regulation' of new types of aircraft, as he said the world is on the cusp of a "revolution" in air travel. Sir Stephen Hillier, chairman of the <a href="https://www.thenationalnews.com/world/uk-news/2023/08/21/travel-firms-call-for-stronger-powers-for-regulator-to-fine-airlines/" target="_blank">UK Civil Aviation Authority</a>, said the introduction of radical new designs, including drones and air taxis, could be "the potentially biggest, revolution since the invention of the jet engine." The UK is building infrastructure to host electric vertical take-off and landing (eVTOL) aircraft, which are designed to land and take off like helicopters, but are powered by electricity, and can sustainably travel between cities and airports. Speaking to the <i>Financial Times,</i> Sir Stephen warned against "divergence" when it comes to developing these aircraft types, adding that this would “restrict the opportunities for operators”. "What is not helpful to any company really is that you can only licence and fly your product in that country,” he said. Air taxi start-ups such as Germany’s <a href="https://www.thenationalnews.com/business/technology/2022/11/03/saudi-arabias-neom-invests-175m-in-volocopter/">Volocopter</a> and and Bristol-based Vertical Aerospace are already looking to make significant moves in the industry, which analysts say could be worth as much as $1tn by 2040. Global consultancy Deloitte also showed that in 2021 eVTOL aircraft companies recoded $5.8 billion in investments. Reports say that Volocopter wants to be the first to fly commercially in Europe as early as next summer, before the Paris Olympics. It also recently completed a series of <a href="https://www.thenationalnews.com/business/aviation/2023/06/21/air-taxi-maker-volocopter-successfully-completes-first-test-flight-in-saudi-arabias-neom/" target="_blank">flight tests in Neom</a>, the futuristic city being built in Saudi Arabia. The UK regulator has an important role in enabling innovation and fostering technological advances, while focusing 'primarily' on the safety of those who fly and those on the ground, Sir Stephen said. He added that the CAA would work with other states and regulators "to take on that enormous challenge of regulating for the future in a collaborative way.” The British authority has rejected claims that it is falling behind in the regulation of new aircraft types. It revealed that it has developed considerable regulatory guidance for the industry, including on how eVTOL can operate at aerodromes and vertiports. Last year, Vertical Aerospace became the first eVTOL company in the UK to fly after receiving a test permit from the regulator. Earlier this year, it also received a Design Organisational Approval, enabling it to advance work on a four-passenger eVTOL vehicle. The regulator says it is collaborating with industry and government on reducing emissions in aviation, exploring different fuel sources and supporting the government’s net zero ambitions.