speed record set by scramjet - fair?

"gatt" wrote in message ...
"Don French" wrote in message

Regardless, it seems to me that the rocket's speed has to be
subtracted from the jet's speed to arrive at the actual jet speed when
you talk about the world's record for speed of a jet plane.

Hmm. Would you say the same for Yeager and the X-1, it having been dropped
from the belly of another aircraft, or is your particular question related
just to the rocket?

In the same vein, many early airplanes needed a catapult to get up to
flying speed, including the Wrights' planes away from Kitty Hawk's
winds. Doesn't make them any less amazing.

Wikipedia makes an interesting point as well... that high-speed jets
taking off from an aircraft carrier need a catapult launcher to get
them up to flying speed. (Obviously the jets can also take off with a
long enough runway, but the similarity is that an assist to get to
speed shouldn't negate the accomplishment, in many people's opinions.)

Best, Kev

Peter Duniho wrote:
Robert Briggs wrote:

I simply think that your wording about "the scramjet [being] the
*entire* source of the speed", rather than its being "sufficiently
powerful to complete the acceleration to Mach 10" (or something to
that effect) is a tad loose.

It is the entire source of the speed.

I'm not convinced, but we seem to be disagreeing about semantics,
rather than about aeronautics.

An engine sufficiently powerful to accelerate the test vehicle from
Mach 9 to Mach 10 is sufficiently powerful to accelerate the test
vehicle from 0 mph to Mach 10.

Sufficiently powerful to accelerate the test vehicle from 0 mph to
Mach 10, yes; actually capable of doing it, no because of the nature
of the beast.

The rocket used to launch the scramjet has nothing to do with how
powerful the scramjet is, or its final speed. Only the scramjet
itself does.

The scramjet (with the aerodynamics and structural integrity of the
test vehicle) sets the *possible* final speed, but the bomber and
the rocket make an essential contribution to getting there.

Kevin Darling wrote:

Wikipedia makes an interesting point as well... that high-speed jets
taking off from an aircraft carrier need a catapult launcher to get
them up to flying speed. (Obviously the jets can also take off with a
long enough runway, but the similarity is that an assist to get to
speed shouldn't negate the accomplishment, in many people's opinions.)

The assistance doesn't *negate* the accomplishment.

However, if the assistance is *necessary* then the accomplishment
is of something slightly different.

Recently, Robert Briggs posted:

Kevin Darling wrote:

Wikipedia makes an interesting point as well... that high-speed jets
taking off from an aircraft carrier need a catapult launcher to get
them up to flying speed. (Obviously the jets can also take off with
a long enough runway, but the similarity is that an assist to get to
speed shouldn't negate the accomplishment, in many people's
opinions.)

The assistance doesn't *negate* the accomplishment.

However, if the assistance is *necessary* then the accomplishment
is of something slightly different.

Perhaps the question at hand is the nature of the accomplishment; as I see
it, the accomplishment is getting a scramjet to work in the real world.
That is pretty amazing, IMO. Another accomplishment is that the _jet_ was
operating at Mach 10; equally amazing, as no other jet can do so, AFAIK.
The launch method would seem to be pretty much irrelevant to those
accomplishments.

Regards,

Neil

"Todd Pattist" wrote in message ...
(Don French) wrote:

snip
The temperature of the leading edge of the tail was 2600
degrees F on the Mach 7 flight. They rebuilt flight
surfaces to get to 10.


"It is possible to fly without motors, but not without knowledge and skill."
Wilbur Wright



Rebuilt what flight surfaces?

"Todd Pattist" wrote in message ...
"Blueskies" wrote:

Rebuilt what flight surfaces?

They partially rebuilt the fins and added a carbon-carbon
composite material to the leading edges of the fins, nose
and wings to handle the higher temperatures. Heating was
expected to double over the Mach 7 flight.

"It is possible to fly without motors, but not without knowledge and skill."
Wilbur Wright

I thought you were saying that they rebuilt the mach 7 plane, which of course was lost in the ocean. I guess you are
saying that they rebuilt the mach 10 airframe before the flight to better handle the temps...