I went on board two Concordes, including the first prototype, at Paris's air and space museum. Concorde, retired in 2003 due to costs and a crash, flew at more than twice the speed of sound. Boom ...

Planes are slow, and apart from the Concorde, they reached peak speed around 40 years ago, flying under the speed of sound. This means that no matter what you pay, there is a cap to how fast you can ...