*SWAT MAGAZINE ISSUE NINE: SEPTEMBER 1998*
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|		           .Rocketry Part 1.			     |
|                        By -=The Firestarter	     		     |
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Ok there are several files out there on rocketry, most of them are
similar, although you can still use the information it is infact
American so I have wrote this file, I have been "into" rocketry for
around 5 or 6 years, so I know what i'm on about.

1) The Engine:


   ____________________________________________________
   |____________________________________________________| -- cardboard
    \ clay   | - - - - - - - - - - | * * * | . . . .|c|            casing
     \_______|  - - - - - - - - -  | * * * |  . . . |l|
       _______ - - - thrust - - -  | smoke | eject  |a|
     / clay  |  - - - - - - - - -  | * * * | . . . .|y|
    /________|_____________________|_______|________|_|__
   |____________________________________________________| -- cardboard

The clay nozzle is where the igniter is inserted.  When the area labeled
"thrust" is ignited, the "thrust" material, usually a large single grain of a
propellant such as black powder or pyrodex, burns, forcing large volumes of
hot, rapidly expanding gasses out the narrow nozzle, pushing the rocket
forward.

     After the material has been consumed, the smoke section of the engine is
ignited.  It is usually a slow-burning material, similar to black powder that
has had various compounds added to it to produce visible smoke, usually black,
white, or yellow in color.  This section exists so that the rocket will be
seen when it reaches its maximum altitude, or apogee.

     When it is burned up, it ignites the ejection charge, labeled "eject".
The ejection charge is finely powdered black powder.  It burns very rapidly,
exploding, in effect.  The explosion of the ejection charge pushes out the
parachute of the model rocket. It could also be used to ignite the fuse of a
bomb...

     Rocket engines have their own peculiar labeling system.  Typical engine
labels are: 1/4A-2T, 1/2A-3T, A8-3, B6-4, C6-7, and D12-5.  The letter is an
indicator of the power of an engine.  "B" engines are twice as powerful as "A"
engines, and "C" engines are twice as powerful as "B" engines, and so on.  The
number following the letter is the approximate thrust of the engine, in
pounds. the final number and letter is the time delay, from the time that the
thrust period of engine burn ends until the ejection charge fires; "3T"
indicates a 3 second delay.

Got that, (Yes I did copy it from the cookbook) Ok, you can only get
A to D rocket engines in this country. They cost around £5 for three
engines, the 1/2A engines cost £3.50 for 4 engines and the D engines
cost £15 for three, A B and C engines cost about £5 for three. D type
engines are the most powerful, and 1/2A are the least powerful, although
all types are fun. B and C type engines are good for making RPG's
(Rocket propelled grenades) but I will come to that.
Today we will deal with the construction of a simple rocket. The rocket
I am going to describe is not very dangerous although thay are fun.

2) Basic rocket production

Materials:
1 packet of 1/2A 10-3 engines Cost: 3.50 for 4
Ice cream sticks
Super glue
Small section of straw

1) Cut the Ice cream sticks in half and sand the ends do that
   they are smooth.

2) Stand the rocket engine upright and apply a thin layer of glue to
   body near to the bottom.

3) Stick the Ice cream sticks to the bottom of body and the straw to the 
   middle it should look like this:
      ___
     |   | <- Top of rocket engine
     |   || <- Straw
 ____|   |____
(______|______) <- Ice cream stick

Building an igniter is simple, just a 9v battery and some wire. You can
use fuse wire if you want. I made one like this using a 1/2A 10-3 engine
and it went about 300 meters at a 45 degree angle.

Once the glue has dried let's launch!

To send you rocket horizonaly you will need a coat hanger or a piece of
wire shaped like this:
     ____________
     |
     |
     |

Now slide the straw over the wire, insert your igniter or fuse and ignite.
You rocket should go some way, as long as you had the fins centeral. If
not, and you launch the rocket skyward it will spiral and leave a cool
smoke trail, try not to lauch these near houses, I did, it went wrong and
arced straight into a window.
This method can be done on any size engine. Experiment, next month you'll
need your basic rocket production knowledge. 

3) Modification to engines:

1) for A to D engines: Cut up a load of paper caps and put them in the
   end of the engine (where the ejection charge is) and epoxy the end
   shut, this can make a loud bang once the charge goes off.

2) Add magnesium or aluminum powder to the end of the engine and epoxy
   it shut, this will give off a large white flash.

3) Scrape away the end clay to reveal the black powder, this is used
   when attaching explosives.

Next month: How to build a rocket with a payload and how to safely
attach warheads.