speed record set by scramjet - fair?

Peter,

You apparently never took high school physics. Look up Newton's first
law of motion, the law of inertia. The scramjet only had to provide
enough power to overcome the friction of air to continue at Mach 9.5
forever or until it hit something, like the earth. To accererate the
jet from Mach 9.5 to Mach 10 takes exactly the same amount of power as
accerating from 0 mph to Mach 0.5, not very much. And that is all that
the scramjet did.

Yes, if you towed a Yugo behind a Porsche, and released it at 150 mph,
it would continue at 150 mph if there were no friction of air and
road. But it could not accelerate to 180 because the means of
propulsion depend on that same friction, unlike a jet plane, which
does not use the friction, but only has to overcome it.

This is elementary physics, a subject that it seems fewer and fewer
people have a grasp of these days.

As to the media, yes I know the media gets almost everything wrong.
But the speed record claim was the topic of my post, not whether there
was a significant accomplishment in running a scramjet in an aircraft
going Mach 10.

-- Don French

I never said it wasn't a successful test, but the only thing touted in
the media was the speed it achieved and the world record it set for
speed

Who cares what the media says? If you know anything about aviation, you
know as well as the rest of us that the media does a pretty poor job of
getting facts straight, especially for technical issues like this one.

and attributed that speed to the scramjet, not the rocket.
That was just wrong. The speed was almost entirely a result of the
rocket's velocity and had nothing to do with the scramjet.

Todd already pointed out the fallacy of that statement. The fact that the
scramjet *accelerated* to the maximum speed clearly shows that the scramjet
is, in fact, the *entire* source of the speed. It produced enough thrust to
maintain Mach 10.

Your statement is like saying that if you towed a Y*go behind a Porsche and
got it up to 150 mph, that you'd be able to then simply disconnect from the
Porsche and still maintain 150 mph in the Y*go. That's simply not true. A
vehicle that can accelerate to Mach 10 from *any* speed and maintain that
speed is capable, all by itself, of that speed. It's just plain incorrect
to claim that "only the last Mach was due to the scramjet" (or however you'd
like to word it).

Seriously,
they could have dropped a Piper cub off that rocket and it could have
maintained Mach 9 for hundreds of miles.

Hundreds? I doubt it. But more importantly, it would NOT have accelerated
to Mach 10.

Should it get the world's
speed record for prop-driven planes?

In your example, the Piper Cub at no point *maintained* a record-breaking
speed.

I think not. And I think that
giving the X-43A a worlds speed record is just as fraudulent.

Well, I'm sorry your incomplete grasp of the facts makes you think that.
Fortunately, those who have a say in the matter have a better understanding
of the situation.

Pete