Concorde was a beautiful plane and a technological marvel. It was a joy to fly, cutting hours off transatlantic trips. Unfortunately it was never a commercial venture. Its development was paid by UK & French taxpayers, and only 13 were sold. Furthermore, the development of subsequent models, through which development costs are often recovered, never took place.

Its successors will be different. Manufacturers are concentrating at the start on the business jet market, developing supersonic craft to whisk CEOs in luxury to their meeting. They are developing innovative ways to solve the problem of sonic booms, and looking to speeds of Mach 1.8.

Analyst Richard Aboulafia estimates a market for 400 business supersonic jets costing $70-80m each. John Rosanvallon of Dassault, whose company is engaged on a supersonic version of its Falcon, thinks that 200 will be the minimum order needed to make a supersonic jet profitable. Several companies are competing, as if in pursuit of a giant X-Prize, but in this case the prize is commercial success. The winner will then have the prospect of a stretched version, a long-range version, an ultra-quiet version, all making use of what they learned on the first model.

The same may be true for private space travel. When the X-Prize is won, the technological advances it took to do so could lead to stretched versions to carry more passengers, and ultimately much more powerful versions to achieve orbit.

The days are gone when governments would spend huge sums to produce prestigious national flag carriers. But the days are upon us when private firms explore innovative ways to tap new and potential markets with privately-financed developments. I welcome this, both as a taxpayer and a future customer.