Aviation is being reimagined for a changing planet: Vertical take-off passenger cars for city centres. Hydrogen powered planes for zero carbon travel. Hyper-sonic flights to take the London to Sydney journey to under two hours.

Kelly Latimer, US Aerospace engineer, flight test pilot, and former Flight Test Director of Virgin Galactic; Rob Miller, Net-zero aviation pioneer and Director of the Whittle Lab at Cambridge University, UK and Daniel Moczydlower, president of the Brazilian future aircraft innovators, Embraer-X, join BBC presenter Caroline Steel on stage in London, to discuss their trailblazing work and answer questions from a live audience at the Royal Geographical Society, London.

Nine Yards, the designers behind the Paris 2024 Olympic skatepark, get to work on their next big challenge: the rebuild of Olympiaplein, one of Amsterdam's oldest and most cherished skating spots. Sean Allsop joins designers Jesper Kuipers and Jeroen Van Eggermond in the Netherlands, as they work through sketches and plans before presenting their vision to local skaters for crucial feedback. Then the team head out onto the building site, with concrete trucks, tight deadlines, and one shot to get the surface smooth for skaters of all levels, before the gates open and a community gets to skate again. We explore how skating has evolved from an underground sport into an established movement, the community within skateparks, and the intricate detail that goes into every park.

The extremist content quietly spreading on TikTok and Instagram, targeting unsuspecting young people. Through what is disguised as innocuous lifestyle content, supporters of jihadist groups like IS and al-Qaeda reach audiences outside their echo chamber. This is a recruitment drive that signals a move from direct operational instructions to “do-it-yourself jihad", with the aim of potentially inspiring lone wolf attacks. The Global Jigsaw explores the tactics used to obscure and evade detection, the challenges this poses for platforms, and how it has become a relentless game of whack-a-mole.

Find out more about BBC Monitoring on our website: monitoring.bbc.co.uk

Contributors: Mariam Soussi, Mina al-Lami Producer: Kriszta Satori, Elchin Suleymanov Presenter: Krassi Ivanova Twigg Music: Pete Cunningham

When Chinese policeman Dong Guangping wrote an article commemorating the 10th anniversary of the 1989 military crackdown on pro-democracy protesters in Beijing, it kicked off a chain of events that led to him serving jail time and losing his job. But it also sparked the beginning of a deep desire to live more freely. So Dong began planning how he might escape China. Just a few weeks ago, back in late May, he finally achieved his dream, having taken the huge risk of crossing China's Yellow Sea in a dinghy to reach South Korean waters. Phoebe Kong, based in the BBC's Hong Kong bureau, explained how rare Dong's achievement really is.

Yemen has faced decades of economic hardship and war, but the khat industry is thriving. Khat is a plant, and when chewed it acts as a stimulant. It is estimated to consume one-third of Yemen's groundwater and occupy much of the country's agricultural land. Dalia Haidar of BBC Arabic has been looking into Yemen's relationship to khat and the problem it can cause.

The Fifth Floor is at the heart of global storytelling on the BBC World Service, bringing you the best stories from journalists in the BBC's 43 language services. We're here to help you make sense of the stories making headlines around the world; to excite your curiosity and to get to grips with the facts. Recent episodes have investigated Russia’s youth armies and how they make soldiers of Ukrainian children; featured the BBC team who were the first journalists to the site of the Nigerian school kidnappings and reflected the effects of internet blackouts in Iran, Uganda and India. If you want to know more about Venezuela’s acting president, Delcy Rodriguez, and the legacy of Hugo Chavez; or how Vladimir Putin’s network of deep cover spies operates; or why Donald Trump signed an executive order granting white South Africans asylum in the US, we have all those stories and more.

This episode of The Documentary comes to you from The Fifth Floor, the show at the heart of global storytelling, with BBC journalists from all around the world.

Presented by Faranak Amidi.

Produced by Laura Thomas and Caroline Ferguson

(Photo: Faranak Amidi. Credit: Tricia Yourkevich.)