Stratoflight is launching peaceful ascents to the edge of space inside a balloon capsule that is powered by hydrogen. Jenny Southan

Joining the likes of Space Perspective in the race for “slow space tourism” is Stratoflight, a French company that has designed a “sustainable” mode of space transport that will allow up to six people (including two pilots) to float up to the stratosphere inside a capsule.

Forget high-octane rockets as seen at Virgin Galactic and Blue Origin, the Stratoflight capsule will ascend 35km above ground level using hydrogen-powered balloon technology, for a gentle cruise into space.

The ogive-shaped capsule (that’s the same shape as a Gothic arch – think both straight and curved lines) measures 8m x 4m x 3m, and comes complete with an “external” viewing platform to allow passengers to step out into space and drink in views of the earth, wearing specially-made pressurised suits.

At this altitude, the planet’s curvature will be visible, along with a horizon spanning from Barcelona to Amsterdam, approximately 1,239km.

The Stratoflight capsule will be able to fly at speeds of up to 140km/h for the return to land, thanks to its aerodynamic shape, while the descent to land is made under a piloted paraglider.

Arnaud Longobardi, airline pilot and co-founder of Stratoflight, says: “Stratoflight provides passengers with multiple exceptional experiences: the ascent to space that feels like a hot-air balloon flight, stepping out on to the viewing balcony, moving into space like an astronaut, and the landing, similar to free flight in a paraglider; all this in a capsule similar to a spacecraft.

“For me, this mission is not only the realisation of my dreams as a pilot but also a technological innovation respectful of the planet.”

To ensure a zero-carbon footprint, the hydrogen needed for take-off will be produced locally at each take-off site via renewable energy, including solar power and wind. Further nods to sustainability are evident in the cockpit design, which is crafted from bio-sourced, recycled or recyclable materials.

French company Stratoflight has partnered with engineering, technology and consulting outfit Expleo to get the project off the ground.

Frédérique Rebout, head of space at Expleo, says: “Making space accessible to all, while respecting the environment, is at the heart of what we believe in at Expleo. Our teams of space engineers have designed this capsule with this dual objective in mind. And we intend to go further.

“We are currently investigating the possibility of making the capsule out of new green composite materials based on bamboo, which would further reduce its carbon footprint. We are proud of our work with Stratoflight and of our contribution to this innovation.”

Reservations for passengers will open in early 2023, with the first flight scheduled for 2025. Stratoflight will also offer several flights each year to people involved in eco-friendly and environmental causes.