Long-haul flights on verge of space age

Keep your seat tilted back during launch, do not unfasten your seatbelt while in space, and try to clench your buttocks as you leave and re-enter the Earth’s atmosphere.

Virgin Galactic introduced its second piloted suborbital space plane, VSS Imagine, in 2021. It has yet to fly.

Keep your seat tilted back during launch, do not unfasten your seatbelt while in space, and try to clench your buttocks as you leave and re-enter the Earth’s ­atmosphere.

The safety briefings before long-haul flights could be very different in future, judging from research funded by the UK’s Civil Aviation Authority.

The regulator said it had begun funding studies into the health impact of suborbital space flights to lay the groundwork for passenger-carrying spacecraft to take off from British soil.

Such flights could blast tourists to their destinations in a fraction of the time, turning holidaymakers into astronauts within as little as a decade.

Studies funded by the CAA, facilitated by the RAF and conducted with King’s College London, have found those taking such flights will not need to be super-fit or young, with older people potentially better able to cope with the rigours of space travel.

A study placed 24 healthy ­people aged from 32 to 80 in an RAF centrifuge at Cranwell to recreate the G-forces felt during the launch and descent of suborbital rocket and spaceplane flights.

It found that G-forces can reach four times the usual force of the Earth’s gravity for 20 to 30 seconds during ascent and peak at six times, or 6G, during descent for 10 to 15 seconds. These forces can create a heavy sensation on the chest, making it more difficult to breathe, and can reduce the intake of oxygen, affect the rhythm of the heart and lead blood to pool away from the brain.

The study noted a rise in heart rate and blood pressure, a dip in blood oxygen and some “greying out” of peripheral vision during periods of high G-force, but found these “quickly return to normal”.

One participant briefly lost consciousness, but with no lasting ill effects. The effects were reduced when the chair was tilted back slightly.

Ryan Anderton, the CAA’s medical lead for space flight, said of suborbital flights: “Physiological responses are likely to be benign for most passengers.”

Dr Anderton said older people tend to have slightly “stiffer arteries”, reducing the pooling of blood away from the brain.

Astronauts need to be extremely fit and undergo years of intensive training.

This will not be necessary for spacebound holiday­makers, but certain medical problems could make it dangerous to experience high G-forces. “For the vast ­majority of people, even older people, that’s not necessarily going to present a problem and there isn’t a detrimental effect long-term,” Dr Anderton said.

“What we’re trying to do in research is determine which individuals might be more susceptible and what we might have to screen them for.”

A separate study, to be presented this week, looked at steps passengers could take to minimise these effects.

“Simple measures such as tensing or squeezing your lower legs or buttocks while the onset of (high G forces) came on were sufficient to reduce (the impact),” Dr Anderton said, explaining that this helped to maintain a strong blood flow to the brain.

“We’re trying to make this ­accessible to anybody.”

The Times