Commercial Supersonics

The Concorde supersonic passenger jet cost an estimated £1.3 billion (around $3.5 billion USD adjusted for inflation) to develop by the time it entered service in 1976.

This joint venture between British Aircraft Corporation (BAC) and Aérospatiale of France was initially budgeted at around £70 million, but costs ballooned due to extensive aerodynamic testing, exotic material use (like titanium and heat-resistant alloys), and developing the Rolls-Royce/Snecma Olympus 593 turbojet engines.

Much of the expense came from pushing the boundaries of supersonic commercial flight, including the complex delta wing design, retractable droop nose, and systems needed to manage high-speed thermal expansion, making Concorde one of the most ambitious and costly aviation projects of the 20th century.