DALLAS (AP) — American Airlines agreed to buy up to 20 Boom supersonic jets that could fly passengers from Miami to London in just under five hours.

The deal brings U.S. airlines another step closer to supersonic travel nearly 20 years after the last supersonic passenger flight by Concorde, a British-French plane that failed to catch on because of the high cost — both for passengers and airlines.

At one point, the Concorde had been ferrying passengers from Miami about three times per week, and crossed the Atlantic in three hours, according to a 1991 report from the New York Times.

But the Miami service ended in March 1991 after the demand for seats dropped, making the 1,350 mph jet hard to justify.

But Boom CEO Blake Scholl insists his company’s plane will be different when it debuts in 2029, with tickets costing about $4,000 to $5,000 to fly from New York to London in about three and one-half hours.

According to Bloomberg, travelers could fly from Los Angeles to Honolulu in three hours, or from Miami to London in just under five hours.

“There are tens of millions of passengers every year flying in business class on routes where Overture will give a big speed-up,” Scholl said in an interview, “and airlines will be able to do it profitably.”

Boom said its plane will have a top speed of 1.7 times the speed of sound, or about 1,300 mph, and carry between 65 and 80 passengers. The company said its plane will also fly entirely on sustainable aviation fuel, often made from plant material, which is currently in short supply and very expensive.

American Airlines said the supersonic plane will change travel.

“Looking to the future, supersonic travel will be an important part of our ability to deliver for our customers,” said Derek Kerr, the airline’s chief financial officer.

Boom, which is based in Denver and plans to build the Overture in North Carolina, says the program will cost between $6 billion and $8 billion. The plane carries a list price of $200 million, although other manufacturers routinely give airlines deep discounts.