Air travel sucks. It's too long, it's uncomfortable, everything's covered in germs, and why are those windows round anyway? How long have I been sitting here? Why does my seat smell like gin and tonic?

If there's one thing flight experts around the world are interested in, it's making our jaunts around the world faster, with this concept jet aiming to get you from London to New York in 30 minutes, and this one in a cool 11 minutes flat. But a concept is just a concept, and there's no guarantee that it will ever get made.

That's why a joint US-Australian military research project called Hypersonic International Flight Research Experimentation (HIFiRE) is so exciting - its technology is well and truly out of the concept stage, and is now being trialled at the world's largest land-based testing range in Woomera, South Australia. 

With the help of aerospace giant Boeing and German space agency DLR, the HIFiRE team plans to complete 10 separate tests with their new engine between 2009 and 2018, in the hopes that it might one day power a hypersonic jet.

Right now, they're testing a scramjet engine attached to a rocket booster - which isn't something any of us are going to be flying to get to our next holiday destination - but with each successful trial, the technology will be whittled down to something that can actually be but into a passenger plane. 

Tests will also be carried out at Norway's Andoya Rocket Range.

According to the Australian defence department, the most recent test was successfully completed yesterday, when the engine was able to reach an altitude of 278 km (172 miles) at a target speed of Mach 7.5 - that's seven times the speed of sound.

"That's far faster than the 'supersonic' Concorde aircraft ever achieved, and passes the threshold for 'hypersonic travel' instead - defined as travel at more than five times the speed of sound," Duncan Geere reports for Tech Radar. "At that speed, you could reach anywhere on the planet in a couple of hours."

Geere adds that the current speed record for a manned, powered aircraft is Mach 6.72, and was set way back in the 1960s by the US X-15 experimental aircraft, so it's about time we made some progress in the field. But the record remains intact for now, seeing as this HIFiRE test was unmanned. 

As well as making sure the engine could get the rocket that high that fast, the HIFiRE team also checked to make sure heat on the outside of the vehicle didn't cause a meltdown during hypersonic flight. 

With everything going smoothly, the next test has been scheduled for 2017, when the team will try to separate the scramjet engine from the rocket booster and get it to fly on its own, one of the team, hypersonics expert Michael Smart from the University of Queensland, told the AFP.

"It's an exciting time… we want to be able to fly with a hypersonic engine at Mach 7," said Smart. "The practical application of that is you could fly long distances over the Earth very, very quickly but also that it's very useful as an alternative to a rocket for putting satellites into space." 

The team estimates that its engine could get you from London to New York in 35 minutes, and London to Sydney in 2 hours.

"It is a game-changing technology… and could revolutionise global air travel, providing cost-effective access to space," Australia's chief scientist Alex Zelinsky said in a statement yesterday. 

So what's a scramjet engine anyway? In the simplest terms, a scramjet engine is supersonic combustion engine that combusts a liquid fuel made with oxygen sucked in from the atmosphere. This makes it way lighter and hence faster than regular aircraft that carry a ready-made supply of liquid oxygen for fuel.

"But in order to work properly and compress the incoming oxygen without the need for moving parts, scramjets need to be travelling faster than the speed of sound, at around Mach 4," Fiona MacDonald explained for us last year.

And, as that 1960s speed record for manned flight says loud and clear - we're not so good at getting passenger planes to hypersonic, or even supersonic, speeds.

That's what makes HIFiRE project so exciting, though - the combined might of the US and Australian military, plus commercial giants Boeing and DLR aren't so interested in unachievable moonshots, so if anyone's going to get us flying at unimaginable speeds around the world, it's these guys. 

We can't wait to see the results of next year's tests.