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Scramjet Test Flight Less Than Successful
Sunthorn writes: "After much hype NASA was forced to destroy the X-43 prototype seconds into the flight after the launch rocket went out of control." The BBC has another story with some pre-flight pictures. Anybody have actual flight photos? Update: 06/02 8:28 PM by michael : Emperor writes "The official NASA take on the X-43
destruction." Update: 06/03 10:18 AM by michael : And someone else sent in this photo gallery, with some really nice close-ups.
From everyone's posts so far, it seems like there are some misconceptions about scramjets.
;-) tells me it's something in excess of Mach 3.
People keep asking why they didn't separate the booster from the scramjet so they can gather as much information from the scramjet as possible. Others are asking why they didn't separate, then let the scramjet operate to gather information.
Well, folks, a scramjet has to get to sufficient speed before it will even work. I am no supersonic aeronautical engineer, but my failing memory (too much LDS in college
Well, in that case, if there's a failure with the booster rocket, there's absolutely nothing you can gather from the experiment. You can't fire the bloody scramjet engine. Separating the booster from the scramjet wouldn't do any good.
Furthermore, we've all seen the damage caused when a 747 hits the water at ~250mph. It breaks apart in a spectacular fashion. It takes years for experts to piece together the reckage to determine what happens. Now, imagine what happens when an object hits the water at 700+mph. It would be pretty damn difficult to get any valuable information from it. Furthermore, the risks to public safety would be incredibly high if NASA let this thing go.
In the end, that's the reason they blew it up. No information can be gathered about the scramjet, and it poses a risk to public safety.
--Be human.
my bugs don't explode in a giant supersonic fireball and rain shrapnel on the test site.
Clearly you're using the wrong programming language. I understand that this is perfectly normal in, say, Perl. :-)
You cannot apply a technological solution to a sociological problem. (Edwards' Law)
scramjet's are very simple mechanically. No moving parts, just hydrogen injectors which combust supersonic oxygen to allow sustained hypersonic speeds.
To get to supersonic speed you need to operate a scramjet, you need a booster rocket of some sort. The booster rocket is what failed in this experiment, careening the entire assembly off course. Rockets are tempermental beasts, unfortunately.
Thankfully, this probably wouldnt set research back much. The mechanical simplicity of the test plane makes it pretty easy to build another. The 30 years of research went into the design of the airbox (and it really is just a box w/ injectors) to make it aerodynamically stable enough for use.
What amuses me is the news stations assertions of "30 minute trip between los angeles and new york!".. well not really. You'd have to speed up to the hypersonic speed safely and then slow down safely. All in all you'd be in hypersonic mode for a couple of minutes, if that. Hardly worth it for the trip. Better for far away destinations.
http://www.aviation-history.com/engines/ramjet.h tm has a comparison of scramjets vs. ramjets.
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Sure the thing tanked before it could complete its mission and NASA didn't get nearly as much data from it as they wanted. They did get some data though. If nothing else, they learned to make damn sure their reasonably reliable Pegasus boosters are thoroughly extra checked over before ignition.
Additionally, they intended to slam this thing into the ocean at the end of the run anyways. The test hardware that was destroyed wasn't all that expensive to begin with (compared to most other things at NASA). Most of the X-43 budget was spent on designing the space plane, not actually building the functioning single use model (not prototype; the eventual space plane is going to be MUCH bigger) that was destroyed today. Given my experience with NASA, I suspect the largest lost cost in today's failure was the Pegasus missile and all the red tape involved in scheduling the launch itself.
NASA still has two or three more X-43's to try again with. And they will try again, and next time it will probably work. Despite what some people here might say, they're not complete fools over at NASA.
I have to wonder just how many people out there were even aware this test was going on today before they saw this news article? How many people would have noticed or cared if it hadn't failed?