Monday, August 13, 2012

What Does It Take To 
Break The Speed Of Sound
Without Leaving The Ground?

On October 15th of 1997 - fifty years and one day after Chuck Yeager broke the sound barrier in an experimental Bell aircraft - another extraordinary event occurred.

And this time, breaking the speed of sound didn't happen in the air.

Well, what does it actually take to break the sound barrier without flying? That's a very good question. Glad you asked. But strap in, 'cause this is some crazy shit.

First you need a car. And not just any old car. You need a car that would make Batman green with envy. 

You need something very much like the Thrust SSC. The Thrust is very powerful, sporting two Spey turbojets. 

Rolls-Royce Spey

What was that? You just bought a Bugatti Veyron with a 1,000 horsepower engine? How nice for you. 

The Thrust SSC has 110,000 horsepower....and yes, you read that right.

Pitiful piston-engined cars. I laugh at you

You see those big nacelles on each side of the SSC? Those aren't there for looks. Those are the air inlets for engines that came from a decommissioned fighter aircraft - the British version of the F-4 Phantom. Yep, this is one car that was aptly named.

Secondly, you need a team of engineers that are dedicated to keeping your car on the ground. 

I'm going to let you in on a secret...jet aircraft fly. 

Yep, real groundbreaking stuff. But you put the engines that once powered a fighter aircraft weighing in at 60,000 lbs. at around 1,400 miles per hour into a car - that car may just want to take off if not dialed in properly. 

Or worse, dig into the ground like it was interested in getting some Chinese food...from the source.

Thirdly, you gotta have a driver. It would be nice if he looked like a GQ model, had an impeccable record with the Royal Air Force and was well-spoken and likable. It helps even more if your driver has balls so big they have their own gravity well.

Enter Andy Green. This is a guy that - when things got off center - went to full opposite lock with the steering wheel in the Thrust SSC - at 650 miles per hour. 


Yeah, this guy

I'd still be shitting myself....months later. Green talks about it like he was negotiating a parking space at Walmart. 

Let's get a few things straight about the Thrust while it's at speed. There is no grip. One degree of deflection upwards on the nose, and 10 tons of air pressure will try to to flip the vehicle onto its back. One degree downwards and the nose plows the front wheels into the ground. These factors have to adjusted while going over 600 milers per hour.

Furthermore, the wheels are aluminum, the steering ratio is half that of a normal car....and worst of all - the rear wheels do the steering.

Uh-huh. Take everything that makes a car handle horribly at high speed - and more paint on one side than the other can certainly do that - and make the damn thing incredibly hard to steer.

The facts are simple. The faster you go, the less lateral grip you have. At extreme speeds, the car is literally sliding sideways - the entire time.

Green became very adept at controlling an uncontrollable car, and he did it at speeds that are hard to imagine for the rest of us mortals.

The Thrust SSC set a world land speed record at Black Rock, Nevada at 763.035 mph. With the new project car, Bloodhound, Andy Green and the team are attempting to break 1,000 miles per hour. 

Shit just got real.

You see, interceptor aircraft have regularly been flying at 1,500 miles per hour for decades now. But to add 500 mph to that speed is extremely difficult. The Blackbird had to be made of special materials, and the Foxbat routinely ruined its jet engines trying to fly at 2,000 mph.

The same is true for the Bloodhound, but different problems have arisen trying to reach the elusive 1,000 miles per hour while still on the ground.

Instead of two antique Rolls-Royce engines like the ones used in the Thrust, the Bloodhound will use one modern jet turbine from the Eurofighter....good for 20,000 lbs. of thrust and 700mph. A hybrid rocket motor - equal to 70,000 horsepower - will take the vehicle the rest of the way to its target speed of 1,000 mph. 

And more importantly, the Bloodhound's shape has to generate zero lift or down-force throughout its entire speed range...all the way up to Mach 1.4.

As Andy Green puts it: "That's really the only requirement for the land speed record, keeping the shiny side up and the wheels on the ground."

Guy has a gift for understatement.

Subscribe to the SPEED Channel on YouTube, and see an interview with Andy Green. Not only does the man have balls that require their own postal code, but he's incredibly modest as well.

1 comment:


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