FEELING SUPERSONIC

IT'S 20 YEARS SINCE THE PUBLIC COULD BUY A TICKET TO FLY ON A PLANE CAPABLE OF BREAKING THE SOUND BARRIER. BUT THERE'S A BAND OF ENGINEERS AND PILOTS WHO THINK COMMERCIAL AIRLINE PASSENGERS ARE ONCE AGAIN FEELING THE NEED... THE NEED FOR SUPERSONIC SPEED

- STEPHEN DOBIE

November will mark the 20th anniversary of Concorde's retirement. And with it, a lengthy pause on regular, paying airline passengers (albeit those with healthy bank accounts) travelling faster than the speed of sound - 343 metres per second, or 761mph (1,224km/h).

Many still mourn the distinctive, dart-shaped aircraft's loss, deeming its costly tickets, urgent fuel use and thunderous sonic booms when it breached the sound barrier as acceptable prices to pay for being propelled across the Atlantic at Mach 2 (over 1,500mph or 2,400km/h).

Supersonic travel looks to be on its way back, though, and in a cheaper, cleaner and quieter form. "Concorde was a technical marvel and well ahead of its time," says Ben Murphy, vice president of Sustainability at Boom. "But it was a nationalistic project that hadn't been built around a viable economical model." Boom is an American company aiming to fly passengers supersonically by the end of the decade on its new Overture aircraft.

"We can build on Concorde's legacy with nearly 60 years of advancement in aerodynamics, materials and propulsion systems," Murphy says, "with the use of sustainable aviation fuel (SAF) enabling the return of supersonic travel in an economical and environmentally sustainable manner."

SAF is seen as the most viable route to reduce the carbon footprint of aviation and can cut a plane's lifetime carbon dioxide emissions by 80 per cent. It can be made by recycling waste materials from landfill and food production, or produced synthetically by carbon capture from the air. SAF can also be mixed in a 50/50 ratio with regular aviation fuel to partially decarbonise the airline fleets operating right now.

TRAVEL THE VIABILITY OF SUPERSONIC 

Overture's propulsion is based entirely around SAF, with Murphy and his team all too aware that the aircraft's green credentials are vital to the project winning favour.