Well the U.S. tested a groundbreaking new hypersonic jet on Tuesday that could revolutionize the way we fly.
The Air Force confirms the test took place, but so far it's not giving any clue whether it was a success or failure.
Chris Lawrence has more on the flight of the WaveRider.
Imagine the trip from Tokyo to Paris taking less than a couple hours.
It could happen way in the future if this hypersonic aircraft being tested takes flight.
The Air Force WaveRider has no pilot or room for cargo,
but as this classic scene from Star Wars shows, looks aren't everything.
What a piece of junk.
She'll make .5 past light speed. She may not look like much, but she's got it where it counts, kid.
The Air Force has been trying to push the WaveRider to mach 6, or 4,500 miles per hour.
That's about five times as fast as a commercial jet could get from JFK to Heathrow.
This would be a very specialized capability...
Analyst John Pike says the only thing in the Pentagon's arsenal that moves that fast now has hydrogen bombs on the front end.
They want a long-range strike capability that's not going to frighten the Chinese or the Russians into thinking that we've launched a thermonuclear attack.
One military report speculated that on the mission to kill Osama bin Laden three years before 9/11.
It took well over an hour for the cruise missiles to hit the al Qaeda training camps, by which time bin Laden was gone.
The report suggests hypersonic weapons could have cut the job to under 15 minutes.
The problem is you can't simulate hypersonic flight conditions in a wind tunnel.
So engineers can't test on the ground before they take to the air, or go slow before they go fast.
This is basically like trying to learn to drive a car that only goes 100 miles an hour.
Not easy, and neither is developing this technology. The Pentagon has spent about $2 billion over the past 10 years.
But the issue is the larger you make the vehicle, the worse the technology works.
So, a hypersonic 45-minute flight from Heathrow to JFK, still a long way off.