The Concorde was supposed to usher in a new era of widespread supersonic commercial flight. Millions of travelers would zip around the world at faster than the speed of sound, or so it was hoped. Instead, due to both high costs and widespread public dismay over sonic booms, the Concorde subsisted only for a few transatlantic routes run by Air France and British Airways. Not long after a fateful Concorde crash outside of Paris in July of 2000 service was suspended, and supersonic transport aviation was dead.

In the face of rising fuel costs and razor thin margins, commercial aviation has responded with larger planes designed to carry boatloads of passengers, like the Airbus A380, or with models geared towards point to point efficiency, like Boeing’s 787. Pure speed has fallen by the wayside. Now it seems the world of private aviation may be picking up where the Concorde left off, and where, for now at least, the airlines refuse to go again.

In a previous article Halogen Guides declared supersonic business jets to be one of the four top private jet trends of the future. Here are the top reasons why billionaires could be flying them very soon, and a few reasons why maybe we shouldn’t get our hopes up just yet.

The Demand is there

While the private jet travel industry has shown itself to be not entirely impervious to the current economic slowdown, demand for new jets remains robust. Gulfstream’s forthcoming G-650 (due to arrive in 2012) has already lined up a host of buyers willing to shell out $58.5 million for the fastest business jet in the skies. For the world’s busiest business executives, cramming meetings far and wide from Jakarta to Seoul to London and back, the efficiencies offered by supersonic travel are enough to justify the expense. For the billionaire boys club, meanwhile, a supersonic private jet will likely be irresistible as the ultimate toy.

Projects are in the works

At least three major supersonic business jets are currently under development. Reno, Nevada-based Aerion Corporation has gathered some 40 down payments of $250,000 from customers looking to get a top place in line for its 8 passenger model which the company say will have a top speed of Mach 1.6 and a range of over 4,600 miles. With a target price of $80 million, those orders are worth over $3 billion, more than enough to cover the estimated $1.2 billion development costs

The Quiet Supersonic Transport (QSST), being developed by Lockheed’s legendary Skunkworks division— the guys who brought you the SR-71 Blackbird as well as stealth technology— under contract from Supersonic Aerospace International, is slated to have a top speed of Mach 1.8 and features an innovative gull-wing design.

An intriguing third player has emerged with the news that business jet stalwarts, Cessna, has entered the ring with plans for a design of its own. Little is known about Cessna’s plans at the moment, but the fact that such a reputable private aviation brand is developing a supersonic jet ought to lend some credence to the movement.

Technology to reduce sonic booms is advancing

The Concorde was relegated to transatlantic flights by the FAA because of the disturbing noise of sonic booms, severely limiting the prospects for commercial supersonic flight. In order for faster than sound business jets to take off, engineers will need to develop a work around.

The QSST is said to feature technology which can mitigate the effects of a sonic boom. The QSST design features an airframe whose subtle curves break up the wave of pressure which generates a sonic boom as a plane passes the speed of sound. The net effect is that instead of creating two echoing booms thundering across the land, the plane passes through a series of mini-booms imperceptible on the ground.

The Aerion SBJ features a less radical design. Still Aerion claims its jet’s wing and airframe design softens sonic booms enough so that they are inaudible on the ground when the plane flies below Mach 1.2. In the United States, where the law prevents planes from traveling faster than Mach 1 no matter how small a boom they make, the plane will be able to cruise comfortably just below the speed of sound.

But…

We’ve seen this before…

Back in the early nineties famed Russian jet manufacturer Sukhoi partnered with Gulfstream in an effort to develop a supersonic business jet. The fruit of that joint venture, the Sukhoi-Gulfstream 21 had tantalizing specs— including a top speed of Mach 2.1 and a service ceiling of 63,900 ft— but flagging demand and high R&D costs tabled the project before it ever left design boards.

While the current supersonic business jet projects appear well-capitalized, and have had no trouble lining up interested customers, cost over-runs are the expectation in the aviation business, particularly in developing such radical new planes.

Aerion, the most well publicized project, in spite of solid financial backing, has still not found a jet frame manufacturer willing to take on the project. Could manufacturers be leery?

High Fuel Costs, Environmental Concerns Linger

With fuel costs spiraling ever and ever upward, will supersonic jets with super-duper fuel burns to match, make much sense? The high operating cost of the Concorde meant the plane almost never was able to turn a profit for Air France or BA, and while the new designs promise to utilize lighter materials, those huge turbofans suck up huge amounts of jet-fuel. In addition to the impact of sonic booms, there is also the concern that supersonic aircraft will pollute more than their slower brethren. There is evidence to suggest that planes flying at the high altitude preferred for supersonic travel cause more direct damage to the ozone layer, and the higher burn rate naturally means more emissions in general. With increased public perception of global warming, one wonders if regulators might step in.

So will billionaire moguls really be cruising from New York to Tokyo in nine hours in the near future? We think so, but we’d be a little more sure when we see some of these planes off the drawing board.