Eugene Leitl wrote:
>
> http://slashdot.org/articles/01/08/28/1551229.shtml
>
> "The Sacramento Bee is running this story about the first powered device
> to achieve "hypersonic" speeds in the Earth's atmosphere. In a series of
> DARPA-sponsored tests, at Arnold Air Force Base in Tennessee, a scramjet
> engine, encased in a titanium projectile, was fired from a 130-foot
> cannon, at an initial velocity of Mach 7.1. The scramjet's engines then
> ignited, and the object moved another 260 feet, in just 30 milliseconds,
> before it came to rest in a series of steel plates designed to halt the
> flight. Peak acceleration: about 10,000 G's. Elapsed time, including
> cigarettes & pillowtalk: less than a second. PS: According to this nifty
> page at NASA, Mach 7.1 is about 5406 MPH, whereas 260 ft, per 0.03
> seconds, is about 5909 MPH."
Yes, rounding downward from 0.033 to 0.03 will tend to do that to a
velocity.
This archive was generated by hypermail 2b30 : Fri Oct 12 2001 - 14:40:21 MDT