For years, Lockheed Martin has been working on hypersonic (Mach 5 and above) aircraft like the SR-72, which could reach virtually any part of the world within a couple of hours. These vehicles have long been seen as distant prospects (the SR-72 might not reach service until 2030 at the earliest), but they now appear to be coming together. Lockheed tells the press that it expects to fly a demonstrator hypersonic aircraft "the size of an F-22" at a cost of less than $1 billion. That's no mean feat when some conventional programs cost more, and it's a hint that hypersonic technology is becoming a practical reality.
This vehicle won't be crude, either. While the existing Hypersonic Air-breathing Weapon Concept project will rely on a booster to reach the altitude where its ramjet kicks in, the new concept embraces the SR-72's "turbine-based combined cycle," where conventional jet tech meets a ramjet. That would let it transition from takeoff to hypersonic speeds without needing a booster engine or helper aircraft in the early stages.
Lockheed's work will still take a while to come to fruition. It's readying a demonstrator aircraft for 2018, and the first hypersonic vehicles in the 2020s (such as HAWC) will likely be weapons. Still, these are positive signs. Although the military is the target customer right now, the developments could lead to hypersonic passenger aircraft that get you across continents in the same time that a short-hop flight takes today.