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alisoncc
6th May 2013, 05:12
The sleek, missile-shaped WaveRider was released from a B-52 bomber 50,000 feet above the Pacific and was initially accelerated by a rocket before the scramjet kicked in.

It reached Mach 4.8 in less than half a minute powered by a solid rocket booster. After separating from the booster, the scramjet engine was ignited, accelerating the aircraft to Mach 5.1 at 60,000 feet.

The flight ended with a planned plunge into the ocean. The WaveRider traveled more than 370 kilometres in six minutes, making it the longest hypersonic flight of its kind. Engineers gathered data before it splashed down.

Experimental hypersonic aircraft hits 4828 km/h (http://www.smh.com.au/technology/sci-tech/experimental-hypersonic-aircraft-hits-4828-kmh-20130506-2j2e6.html)

http://images.smh.com.au/2012/08/15/3555489/bg_hypersonic_plane_X_51A_1-20120815080825831449-620x349.jpg
US Air Force illustration shows the X-51A Waverider set to demonstrate hypersonic flight. Photo: AFP Photo/US Air Force

Slasher
6th May 2013, 05:21
50,000ft? I didn't know B52s could reach that high.

alisoncc
6th May 2013, 05:23
They don't. They lowered the Pacific just to make it look good. :ok:

Loose rivets
6th May 2013, 05:34
The Rivetess explains why a B52 can go as high as it bloodywell wants.


http://img.photobucket.com/albums/v703/walnaze/Florida1026.jpg (http://smg.photobucket.com/user/walnaze/media/Florida1026.jpg.html)

UniFoxOs
6th May 2013, 06:49
Exciting ride for a pilot or pax - 5g according to my rough calcs. Can't imagine what it would be like, I've only experienced 3g for the duration of a loop and 2g for a few minutes.

blue up
6th May 2013, 07:51
So, who was the naughty fellow who loosed off a missile near the western seaboard of France, yesterday? Someone asking ATC if they had anything on radar since a contrail was seen to go vertically up to "about 40,000 feet" and then down again.

A few tense moments in the flightdeck, methinks.

500N
6th May 2013, 07:55
The French did.

It's on line, search for French missile test Western France.

It was a sub launched ICBM that failed.

ExXB
6th May 2013, 09:23
Wonder what the purpose of all this is. Could anyone live through an acceleration to Mach 5 in less than a minute?

No, my vote is for the Solar Impulse - 0 to Mach 0.01 in a couple of hours, but who's counting.

alisoncc
6th May 2013, 10:18
Wonder what the purpose of all this is. Could anyone live through an acceleration to Mach 5 in less than a minute?We can get you from LHR to JFK in 90 minutes, but you will look like a pile of raspberry jelly when you get there. :ok:

arcniz
6th May 2013, 13:13
NEW NICHE FOR FEDEX, EH?

rmcb
6th May 2013, 17:25
We can get you from LHR to JFK in 90 minutes

Shame about the 120 min. hold at JFK!

Mach 4.8 in less than half a minute

Permanent rictus grin - this was the sole passenger at the post launch ball...

http://i.telegraph.co.uk/multimedia/archive/01005/Cherie-Blair_1005101c.jpg

PTT
6th May 2013, 17:45
Wonder what the purpose of all this is. Could anyone live through an acceleration to Mach 5 in less than a minute?The quote states less than half a minute, but:
Mach 5 = 1701.45 m/s
Acceleration from 0 to that speed in, say, 30 secs
a = (vi - vf)/t
a = 1701.45/30
a = 56.715 m/s^2

1g = 9.80665 m/s^2
acceleration = 5.78g

So a constant ~6g acceleration for about 30 secs. Survivable? Maybe, given the correct suit etc.

All that assumes a constant acceleration rather than staged.

lomapaseo
6th May 2013, 20:30
So a constant ~6g acceleration for about 30 secs. Survivable?

What would this be like on the average 40 Yo fat passenger with a touch of diarrhea ?

500N
6th May 2013, 20:32
Messy :O


Don't be a cleaner afterwards !

dead_pan
6th May 2013, 20:36
He or she would be fine, but the people sat behind them would be a little worse for wear.

racedo
6th May 2013, 21:06
We can get you from LHR to JFK in 90 minutes,

However Homeland Security will still take 12 hours to process you and check your luggage.

Ascend Charlie
6th May 2013, 23:25
Not accelerating from zero - you are already being carted around in a B52 at Mach .82

And the acceleration is into the back of your seat, quite tolerable. Like the astronauts lying prone as they go vertical, you will be sitting vertical and accelerating laterally.

IFMU
7th May 2013, 03:28
They finally got one to fly without a failure, good on them. They were contenders for the Collier Trophy in 2010 but lost to the Sikorsky X2.

The acceleration of the waverider under rocket power has little to do with the final application. It was an easy way to get it going fast enough for the scramjet to work. Some years down the road if they fly people the aircraft will be big enough to hold lots of fuel, probably conventional engines too, for the purpose of getting fast enough for the scramjet to work as well as providing the necessary range and endurance.

The solid booster did most of the work and the scramjet took it from Mach 4.8 to Mach 5.1, though they hoped for Mach 6. The magic is that an air breathing engine achieved Mach 5.1. That is speedy.

Bryan

500N
7th May 2013, 03:54
IFMU

I agree, it was good to see them get one going at last.

Isn't the first application of this technology high speed missiles
so they can lob anywhere in the world before people have a chance
to escape ?

IFMU
7th May 2013, 15:43
500N,

Yes and no according to the media:


The Air Force said the four X-51As were built to demonstrate the new technology, not as a prototype for a new weapon system. The program is aimed at paving the way to future hypersonic weapons, hypersonic intelligence, surveillance and reconnaissance, and future access to space, it said.

Bryan

Lonewolf_50
7th May 2013, 17:31
We can get you from LHR to JFK in 90 minutes

However Homeland Security will still take 12 hours to process you and check your luggage

Best post. :D:}

AtomKraft
7th May 2013, 17:59
Well at least this proves (finally) that they haven't had a scramjet powered replacement for the SR-71 flying around for years. ;)

PingDit
7th May 2013, 22:58
Of course it does Atom :suspect: