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A New Engine Could Bring Back Supersonic Air-Travel (economist.com)
An anonymous reader shares a report (may be paywalled): Every morning, time once was, a giant roar from Heathrow Airport would announce the departure of flight BA001 to New York. The roar was caused by the injection into the aircraft's four afterburners of the fuel which provided the extra thrust that it needed to take off. Soon afterwards, the pilot lit the afterburners again -- this time to accelerate his charge beyond the speed of sound for the three-and-a-half hour trip to JFK. The plane was Concorde.
Supersonic passenger travel came to an end in 2003. The crash three years earlier of a French Concorde had not helped, but the main reasons were wider. One was the aircraft's Rolls-Royce/Snecma Olympus engines, afterburners and all, which gobbled up too much fuel for its flights to be paying propositions. The second was the boom-causing shock wave it generated when travelling supersonically. That meant the overland sections of its route had to be flown below Mach 1. For the Olympus, an engine optimised for travel far beyond the sound barrier, this was commercial death.
That, however, was then. And this is now. Materials are lighter and stronger. Aerodynamics and the physics of sonic booms are better understood. There is also a more realistic appreciation of the market. As a result, several groups of aircraft engineers are dipping their toes back into the supersonic pool. Some see potential for planes with about half Concorde's 100-seat capacity. Others plan to start even smaller, with business jets that carry around a dozen passengers. The chances of such aircraft getting airborne have recently increased substantially.
Supersonic passenger travel came to an end in 2003. The crash three years earlier of a French Concorde had not helped, but the main reasons were wider. One was the aircraft's Rolls-Royce/Snecma Olympus engines, afterburners and all, which gobbled up too much fuel for its flights to be paying propositions. The second was the boom-causing shock wave it generated when travelling supersonically. That meant the overland sections of its route had to be flown below Mach 1. For the Olympus, an engine optimised for travel far beyond the sound barrier, this was commercial death.
That, however, was then. And this is now. Materials are lighter and stronger. Aerodynamics and the physics of sonic booms are better understood. There is also a more realistic appreciation of the market. As a result, several groups of aircraft engineers are dipping their toes back into the supersonic pool. Some see potential for planes with about half Concorde's 100-seat capacity. Others plan to start even smaller, with business jets that carry around a dozen passengers. The chances of such aircraft getting airborne have recently increased substantially.
Travel of any kind follows the same rules of economics as everything else, in that the least expensive thing that meets the wants and needs of the buyer generally wins out. Travel has the added component of wanting to reduce duration as much as practical, but even then, cost wins.
Extremely fast suborbital sounds cool, but the vast majority of people can't justify the cost. Even the ultra-rich can't justify it, even if they can afford it.
By contrast, at one time Concorde had promo-packages available, my wife as a child got to fly Concorde back from the UK as part of a vacation package her parents found. It wasn't cheap, in the eighties it was probably a thousand dollars a person for them, but it was still far cheaper than anything suborbital would cost at this point.
Do not look into laser with remaining eye.
It really isn't that far of stretch...
Imagine Just Read the Instructions being manufactured and deployed en masse. You have landing zones essentially anywhere there is water - Lake Erie for Buffalo, Back Bay for Boston (ha! jk, I mean near Logan), Upper Bay for NYC, Biscayne Bay for Miami, etc etc all over the world.
That's anywhere, with sea access, in the world in 30 minutes.
Flight, from launch to landing, is already 100% automated / controlled from ground.
"And this is now. Materials are lighter and stronger. Aerodynamics and the physics of sonic booms are better understood."
And the new materials and better understanding of aerodynamics can be traced back to the R&D responsible for creating the F-22 and F-35. Most of the advanced technology in use today was the result of the well funded military R&D. Cell phones, satellites, GPS, and the very foundation of the freaking Internet started life looking for possible military applications. Hell even TOR started of as a Naval Research initiative and when they determined the end result was not what they wanted they turned the entire project over to a civilian institution for public use.
Drag is really bad from just about Mach 0.8 to about 1.8 or so. That doesn't have anything to do with the engines or anything else you can control. It's a constant known as cD that isn't largely independent of aircraft design.
Meaning you need to cruise at about Mach 2 to have reasonable efficiency in terms of drag.
Supersonic flight isn't just "subsonic flight, but faster". The design of a high speed aircraft is all about how the air flows around the aircraft and through the engines. At Mach 1, which is kinda like "the maximum speed of air", that totally changes. Things work completely differently.
So you have to design your engine for Mach 2, your airframe, etc. All of these will be designed very differently than they would be for subsonic flight. Especially if you intend to fly over land, you're going to need to fly subsonic a significant portion of the time (plus you need to take off and land, and you're not landing at supersonic speeds).
So you have a problem. You need a plane designed to work very well at Mach 2, and it has to be designed to work well subsonic. These are two very different designs. It's hard to have the same plane do well with both. It's kinda like designing an ocean-going ship that's also a bicycle.