In the decades to follow, the speed of aviation stagnated—and even regressed. The SR-71 retired from service in 1999, and no commercial airliner in service today flies at Mach 1 (the speed of sound), much less the Mach 2 speeds reached by the Concorde. The time required to fly from Los Angeles to New York or across the Atlantic Ocean is no different than it was 40 years ago for the average airline passenger.

The initial progress and current stagnation of airplane speeds is plain to see by looking at manned, air-breathing flight airspeed records since the Wright brothers’ first flight on December 17, 1903, which is estimated to have flown at 6 mph. Airspeed record data have been gathered since 1905 by the Fédération Aéronautique Internationale (FAI), an international organization that sets standards for tracking, measuring, and verifying aviation records.

Shortly thereafter, the FAI recorded its first Mach 2 flight in 1958. That speed was matched in commercial flight less than two decades later, a testament to the high level of innovation in air travel during the mid-20th century.

What happened to this high level of innovation in air travel? Civil supersonic aviation was banned over the United States in 1973 because of fears that sonic booms would damage buildings and constitute an intolerable nuisance. The outright ban limited the market for the Concorde to transoceanic routes and destroyed incentives for research and development of new supersonic transports. Since 1973, airplane manufacturers have innovated on margins other than speed, and as a result, commercial flight is safer and cheaper than it was 40 years ago. But commercial flight isn’t any faster—in fact, today’s flights travel at less than half the Concorde’s speed.

If we want to restore mid-century levels of aviation innovation and break the sound barrier again, we must first break regulatory barriers. The FAA should lift its ban on civil supersonic flight. Legitimate concerns about supersonic flight can be handled by specific policies that address concerns directly, such as a clear standard from the FAA for acceptable noise levels. It would be a shame to suffer another four decades of aviation stagnation.

This first appeared at the Mercatus Center.

The blue trend line shows the rapid pace at which the airspeed record was bested in the first three-fourths of the 20th century. The fastest growth in achievable airspeeds occurred in the decades following the Second World War. The sound barrier was famously first broken by Chuck Yeager in 1947, but the FAI did not recognize Yeager’s flight for the record because the plane was rocket-powered and launched by a drop from a B-29 bomber. The first supersonic flight recorded by the FAI was made in 1955 by US Air Force Colonel Horace Hanes.