[FPSPACE] Iranian sounding rocket

[Allen Thomson]

--- robot at esper.com wrote:

> Years ago (Nov/Dec 1998), I had done a back o' the envelope
> calculation per request of ABC News, as to whether the Iraqis under
> Saddam could, with a Scud-B, lob half a tonne of sand with a small
> bursting charge high enough to pose a threat to the nascent Space
> Station. 

There is a "1/2 Rule" that I learned lamentably late in life that's
very handy when doing this sort of thing. One notes that it apparently
ignores drag losses during early flight, but for rule-of-thumbish,
generally-what-we're-talking-about purposes that's probably acceptable.


http://www.amacad.org/publications/rulesSpace.aspx
http://www.amacad.org/publications/Section_8.pdf Appendix B for details

The Physics of
Space Security
A reference manual
David Wright, Laura Grego, and Lisbeth Gronlund
ISBN: 0-87724-047-7

"A useful rule of thumb is that a ballistic missile that can launch a
given payload to a maximum range R on the Earth can launch that same
payload vertically to an altitude of roughly R/2. This relation is
exact in the case of a flat Earth and therefore holds for missiles with
ranges up to a couple thousand kilometers (the Earth appears
essentially flat over those distances, which are small compared to the
radius of the Earth). But the rule continues to hold approximately for
even intercontinental range missiles (see Appendix B to Section 8).

"Changing the payload of the missile changes both its maximum range and
its maximum altitude, but these two distances continue to be related by
the 1/2 Rule. For example, a Scud missile, which has a maximum range of
300 km with a one-ton payload, would be able to launch a one-ton
payload vertically to an altitude of 150 km. By reducing the payload,
the Scud missile could launch it to higher altitudes. Reducing the
payload of a Scud missile by one-half, to 500 kg, would give it a
maximum range of about 440 km or allow it to launch the payload to a
maximum altitude of about 220 km. Reducing the payload to 250 kg would
increase the maximum range to about 560 km, and the maximum altitude to
about 280 km."