Fifty years ago, the first Concorde prototype roared over the 28th International Paris Air Show, initiating a supersonic era that enabled flight from New York to London in just over three hours. Four years later, in 1973 — only 70 years after the Wright brothers first took to the skies — the Concorde made its debut transatlantic journey.
This exciting era of civil supersonic flight, however, would last only 30 years. Supersonic flight has largely remained dormant since the Concorde’s final flight in 2003. Today, that same New York-to-London flight takes about seven hours. While technology flourished since 1973, we’re still travelling by air at about the same speeds that we were before landing men on the moon.
Fortunately, we are now seeing a change in course. US president Donald Trump’s push to remove regulatory barriers to innovation means a return to supersonic flight for civilians is just over the horizon. Last fall, the president signed into law the Federal Aviation Administration Reauthorisation Act of 2018. This groundbreaking, bipartisan legislation directed the FAA to demonstrate global leadership in the domain of “safe and efficient operation of civil supersonic aircraft.”
We envision a world where safe, quiet and efficient aircraft take to the skies at the speed of sound and revolutionise global air travel.
Recently, during the 53rd International Paris Air Show, acting FAA administrator Daniel Elwell announced that his agency is following through with this direction by publishing the first in a series of proposed rulemakings, marking the start of the first redesign of supersonic regulations in decades. The proposed rule making represents a long-overdue reorganisation and clarification of the supersonic testing process. This is also the start of a comprehensive set of proposed changes, some of which may be released later this year, that will allow the United States’ research and development ecosystem to revisit the three-hour flight across the Atlantic.
In parallel with FAA efforts to enable testing of supersonic aircraft, Nasa is conducting cutting-edge research to produce a supersonic aircraft that reduces the sonic boom to a “gentle thump”. Manufacturing has begun on Nasa’s X-59 Quiet Supersonic Technology flight demonstrator, and by 2021 this new aircraft will conduct its maiden voyage, flying faster than the speed of sound while producing a perceived sound similar to that of a car door closing instead of a traditional loud sonic boom. The X-59 programme aims to demonstrate that the shaping of the aircraft can significantly reduce the perceived noise of sonic booms, and the technology developed in this programme could be directly adapted to future commercial aircraft designs.
Some of the most promising opportunities to see the return of supersonic air travel in the near term are on long, oceanic routes that will bring the world closer together. However, efforts by innovators in the private sector and Nasa to deliver quieter supersonic aircraft — some even barely noticeable at altitude — may soon enable a reconsideration of the almost 50-year-old prohibition of supersonic flight over land.
The FAA Reauthorisation Act also sets a bold timeline to address one of the most significant barriers to civil supersonic flight: landing-and-take-off noise. While aviation enthusiasts could appreciate the roar of the Concorde taking off with all four engines in afterburner, airport noise is a concern in many communities. Aircraft engines and components optimised for supersonic aircraft have different properties than those built for subsonic flight, and regulations may need to appropriately recognise these differences.
In crafting a specific supersonic noise standard, any proposed regulatory changes must consider potential community and economic impacts as well as technological practicalities for this new, updated category of civil aircraft. The FAA Reauthorisation Act calls for the FAA to propose new standards on landing-and-take-off noise for supersonic aircraft no later than March 2020. We call on the international community to work with our regulators toward a noise standard that will enable civil supersonic flight globally.
Subsonic aircraft engines have benefited from decades of fuel and noise optimisations, while supersonic aircraft engines have seen little research and development outside of military channels. The FAA’s work on supersonics testing and potential noise standards will promote innovation, allow industry to close this technology gap and ensure the highest levels of safety.
Today’s buzz surrounding civil supersonics — both small business jets and Concorde-size airliners — is palpable. Low-sonic-boom research and potential regulatory changes are keys to success in this emerging market. Beyond supersonic flight, Transportation Secretary Elaine Chao has pursued an innovation and safety agenda on many fronts in aerospace, including unmanned aircraft, electric aircraft with vertical take-off and landing, and even commercial space travel.
Since 1903, the United States has led the world in flight. By removing innovation-killing regulations, the president will continue that legacy for years to come. We envision a world where safe, quiet and efficient aircraft take to the skies at the speed of sound and revolutionise global air travel. It’s time to fly supersonic again.
— Washington Post
Michael Kratsios is deputy assistant to the US president for technology policy at the White House. He is Donald Trump’s nominee for chief technology officer of the US.