feasability of handheld energy weapons?
John Schilling
linc...@sable.ox.ac.uk (rupert smith) writes:
>there is some data that i need cleared up, and if anyone can supply it I'll
>be grateful..
>firstly what is the efficiency of the best laser/maser in production today?
Production semiconductor diode laser arrays can achieve efficiencies of
40% or so, and experimental demonstrations of 80% efficiency have ocurred.
This type of laser is capable of generating high energy beams, but the
beam quality may not be adequate for weapons use. Either some clever
tricks currently in the laboratory stage have to work out, or you have
to fall back to CO2 or diode-pumped YAG lasers which get maybe 10-15%
efficiency.
>secondly what is the energy density (mass and volume) of a modern capacator
>or the best battery? and also for chemical propellants, as a comparison...
The best available batteries are good for about 500 kilojoules per kilogram,
or 1000 kJ per liter. However, the *power* density is less impressive; it
is usually not possible to get the energy out in less than a minute or two.
Again, clever tricks at the laboratory stage of development may change this;
I've seen reports of a 400 kJ/kg battery that can discharge in less than
five seconds - but not nearly ready for production, and with the bothersome
limitation that it only works at temperatures above 400 degrees centigrade.
Chemical propellants are typically at about the 5000 kJ/kg level, and have
no trouble with high-rate discharge.
>also, can anyone supply typical bullet weights/muzzle velocities for a
>typical automatic pistol?
9mm NATO pistol bullet - 8 grams, 400 meters per second. 640 kJ energy
.45 Automatic Colt Pistol - 15 grams, 275 meters per second. 570 kJ energy
.22LR target pistol - 2.5 grams, 300 meters per second. 110 kJ energy
Note, however, that these numbers cannot be directly compared with a
hypothetical laser weapon. The human body is mostly water, which is
not particularly strong but absorbs heat better than just about anything
else around. So a laser weapon will probably need to deliver an order
of magnitude more energy to produce the same effect as a bullet.
--
*John Schilling * "You can have Peace, *
*Member:AIAA,NRA,ACLU,SAS,LP * or you can have Freedom. *
*University of Southern California * Don't ever count on having both *
*Aerospace Engineering Department * at the same time." *
*schi...@spock.usc.edu * - Robert A. Heinlein *
*(213)-740-5311 or 747-2527 * Finger for PGP public key *
rupert smith
there is some data that i need cleared up, and if anyone can supply it i'll be
grateful..
firstly what is the efficiency of the best laser/maser in production today?
secondly what is the energy density (mass and volume) of a modern capacator or
the best battery? and also for chemical propellants, as a comparison...
also, can anyone supply typical bullet weights/muzzle velocities for a typical
automatic pistol?
thanks in advance
------------------------------------------------------------------------------
rupert smith linc...@sable.ox.ac.uk http://info.ox.ac.uk/~linc0015
"if you believe your dreams'll come true
then sleep
is all you'll ever do." -- marion, sleep.