Comments on: SpaceShipOne: A giant leap for high-tech vets?

Paul Allen's galactic baby flies briefly toward outer space as it begins the first phase of a historic endeavor.

SpaceShipOne Appears to Be Not So Special as the X-15 of 45 Years Ago

I guess that a lot of young people do not realize that the NASA and the US Air Force accomplished starting in 1959 all of the feats that SpaceShipOne has so far.

The X Plane project from 1959 to 1968 flew X-15s to 108 kilometers, using piggyback methods exactly the same as SpaceShipOne.

Isn't it the case that these people are collecting a lot of credit for originality that is deserved by the really original people who risked their lives and were truly inventive over 40 years ago?

Maybe someone can enlightenmen me on this?

Re: X-15 vs SpaceShipOne

Dear Louis,

To put my comments in context: I'm a registered mechanical engineer with extensive graduate work, over 25 yr's experience, and a pilot.

I would submit that this flight differs substanually from the X-flights conducted by the USAF, NASA and NACA during the '50's & 60's.

First, it is a strong understatement to say that this was done with a small fraction of the funding (and none of it governmental).

Second, notice that the test pilot was not a formally trained pilot. He hadn't even a taste of the formal training that I recieved while a naval aviation cadet. Also notice that he probably wouldn't even have qualified on the physical to get into flight training -- even if they waived the maximum age requirement. There was no ejection seat, no high performance flight suit, and only a thin skin of plastic separating the pilot from vacuum and intense heat/cold. It had to be much simpler than the X-15 for this human/machine combination to work.

Third, the materials used were not aluminum, stainless steel, berylium, titanium or other exotic materials, they were fiber-plastics -- very similar to those used in hobby planes and boats that you or I might obtain and use.

Fourth, the fuel was not the traditional high-energy propellants that the "pros" customarily use in order to lift their heavy-weight machines; it was nitrous oxide (what dentists used to use as anesthesia and known as "laughing gas") and rubber (with a specific impulse rating that commands but snickers and giggles from those with the big budgets.)

Fifth, the aerodynamics of re-entry was completely out-of-the-box, not previously tried nor even previously considered (to the best of my knowledge)... but completely and uniquely appropriate for this technique: they turned the craft into a high-drag, supersonic shuttle-**** and back again DURING UNPOWERED reentry. Not even the first first in-flight, configurable winged plane, the multi-million dollar F-117, could match that.

Sixth, instead of using an existant B-52 modified only to carry the space vehicle as an external bomb, this small team had to design their own lift vehicle on limited funds and in months compared to years.

Technically, the X-15 flights were not nearly the excursions into the unknown as the X-2?? or X-1?? flight that successfully broke the sound barrier was. Of all of the flights, governmental or private, that one was the most dangerous, least predicatble, most technically challenging and had by any measure, the largest impact upon flight.

Granted, that the X-15 achieved about 30% higher altitude over the course of its multi-year program, but this is a small extension of altitude in airless, frictionless space. The challenge to this craft would be to lose the potential energy represented by that altitude or to beef the "feather" up to dissipate the extra converted kinetic energy on the way down. To me that seems to be a smaller challenge than those met in the first five items that I listed.

I would be interested in any additional thoughts that you might add to this discussion, as well as any exceptions to the above points. Thank you for an interesting talking point.

Very Truly Yours, Al

Stiil an achievement

Considering that "private Entreprise" was able to put this vehicle into "near orbit" in a very limited time and with most certainly lesser funds than the Federally Planned flights, is an achievement in itself. I am sure that American taxpayers are rejoicing. Regards from Canada and Bravo to the public sector.