Fig.1 Combat Zone

Fig.2 Seabed Contour Chart


HUNTER KILLER
-------------

by R. Hopkins

Loading the Game
The solo program is loaded by typing LOAD "" or
LOAD "HUNTER". If you have any problems with
tape loading, consult pages 141-148 of the Sinclair
ZX Spectrum handbook. The program loads in four
sections; only stop your recorder when the display
showing the stars and your position comes up.

The dual version loading is covered in the "Dual
Game" section.

The Game
You are the Commander of an "S" type submarine
on an important mission off the coast of Helegoland
(Germany) and Denmark during the Second World
War. The area is shown in Fig.1. Inside this area is
an enemy submarine that you must hunt and sink
to complete your mission successfully. You must
not stray outside your area or you will be sunk by
destroyers which are hunting you. The coast is
heavily mined and if you sail too close to it you will
probably hit a mine; if not you will run aground. The
seabed contours are shown in Fig.2.

"S" Type Submarine
The "S" type submarine was one of the most
successful classes of British submarine, being the
largest single group of submarines ever built for the
Royal Navy. The class remained in service and
production throughout the Second World War. They
had an overall length of 217 ft. and displaced up to
1000 tons, and a crew complement of 44. The
diesel engines developed 1900 SHP giving a
maximum speed of 16 knots; the electric motors
developed 1300 SHP and gave a speed underwater
of 9 knots. The maximum diving depth was 300 ft.

Sailing a Submarine
A submarine sails like a normal ship, left rudder (<-)
will turn you to port and right rudder (->) will turn
you to starboard (remember that left and port both
have four letters). You can also turn using left and
right movements of the joystick. The maximum
rudder angle is 70 degrees. The rudder sensitivity
depends on your speed, and the faster you are
sailing, the faster you will turn.

A submarine has two engines; one diesel, one
electric. On the surface you should use the diesel
engine but, because diesel engines need air to run,
they cannot be used under water. In this situation
you must use your electric motors; diving
underwater with diesel engines will cause a

warning light to flash and, if this warning is
disregarded, you will irreparably damage your diesel
engines. The electric motors run off batteries that
are charged up by the diesel engines when on the
surface and if you allow the batteries to run down
by spending long periods of time underwater, you
can leave yourself with too little power to surface
and re-charge, so watch the battery charge
indicator.

Diesel engines are more powerful than the electric
motors; they will give you a top speed of 16 knots
compared with only 9 knots under electric power.
Pressing the E key will change your engines from
diesel to electric or vice-versa, and an indicator in
the main control room will show you which motors
you are using.

To dive the submarine two actions must be taken.
You must first fill your ballast tanks by using the N -
Neutral buoyancy - key. As the tanks fill up the
indicator at the top left hand side of the control
room will show the water level in the tanks. This will
cause the submarine to sink slowly. To assist in
diving, there are miniature wings on submarines
called hydro-planes. If these are turned clockwise,
pushing the tips downwards, then this will push the
submarine underwater. This is done by pushing the
(v) key (on the 6) or pulling the joystick back.
Remember you will not dive quickly if you don't
take both of these actions.

To stop diving you must level the hydro-planes by
pushing the (^) key (on the 7) or pushing the
joystick forward. You must also empty your ballast
tanks until the ballast indicator is at the half-way
mark. You will now level out at this depth.

To surface, you must do the reverse of diving,
blowing your tanks using the B - Blow - key and
angle the hydro-planes upwards by turning them
anti-clockwise. This is done by pushing the (^) key
(on the 7) or pushing the joystick forwards. Fig.3
shows the positions of the instruments and
indicators in the control room.

Fig.3 Control Room

Using the Periscope
The periscope is in the centre of the control room;
press the P key will raise or lower it, and pressing V
will let you see through it. When you look through
the periscope you will see the surface of the sea
and the target, if it is within visual range. The sea
surface will be higher up the viewing window the
deeper the submarine is sailing; below about 38 ft.
you will be too deep for a periscope view. The
optimum periscope depth is around 34 ft.

To turn the periscope, press O and it will rotate
clockwise in 36 degree increments. Pressing I will
rotate it anticlockwise in 6 degree increments.

Fig.4 Periscope View

Below the periscope lens are four digital readouts.
These are shown in Fig.4. The first shows the
periscope angle, 0 degrees is dead ahead, the
second is heading - the way the ship is pointing,
which is not necessarily the way it is moving. The
third gives the distance to the enemy, updated only
if the enemy is within range of the instruments, and
the fourth shows the number of torpedoes running.

Press V to return to the control room.



Radar, Asdic and Depth Recorder
The Asdic set displays a north up true bearing for
targets within a four mile range. It comes on
automatically at depths greater than 10 ft. and you
will hear its characteristic "ping". On the surface,
the radar is switched on instead. It has a greater
range - 22 miles - and again is a north up, PPI
display, on which each sweep of the antenna is
seen. Finally, the echo sounder indicates the depth
of water below the keel. Thus, if the boat is rising,
the trace falls, as it does when the submarine
remains level while the sea-bottom shelves off. Fig.2
shows the seabed contour charts and the echo
sounder range is from 200 ft. up to 0 ft.

The Chart Room
The chart room is on the starboard of the control
room and is accessed by pressing the C key. It is
shown in Fig.5. The control room proper slides
across, making room for the chart display as it goes.
Sounder and Asdic sets both remain in view, now
on the left, and both continue to work. On the chart
itself, apart from the local coastline, there is a large
compass rose, the boundaries of a continuous
coastal minefield - m - and a longitude/latitude grid
calibrated at the bottom and right. Inverse figures
give degrees, the others, minutes.

At the top left of the chart a small line radiating
from a small circle points in the direction of the tide

Fig.5 Chart Room

stream. Your own position is indicated by a
miniature submarine - at the left-hand end. Below
the chart can be found tide strength; the log, i.e.
your speed through the water; and the enemy's last
reported position. The position indicator only gives
the minutes part of the position, the degree part is
obvious. For example if the position indicator says
30.2' N, 7.4' E then the full position is 58 30.2' N,
8 7.4' E. This position is only updated if the target
is within range of the sensor that is functioning at
this time. The enemy is always surfaced for the solo
game, and always starts off from some point on the
eastern side of the chart, steering a course with a
lot of west in it, at a random speed up to about four
knots. Your position is not updated while the chart
room is accessed. Pressing the X key will allow you
to exit from the chart room and return to the control
room.

Firing Torpedoes
Torpedoes can be fired dead ahead at a target;
there are only bow torpedo tubes. Pressing T will
prime the torpedoes and fire the first one. Second
and subsequent torpedoes in this salvo are fired
using F. The torpedo count meter will keep track of
the number of torpedoes in this salvo. Salvoes must
be spread in time, not angle.

Torpedoes run at 45 knots and have a range of
three miles. A bubble track gives some indication of
the progress of the torpedoes, though not an
accurate position of the torpedo, of course. If the
salvo has clearly missed, the salvo can be aborted
by pressing A.

Torpedoes cannot be fired unless the rudder is
straight and the boat is maintaining a steady depth
less than or equal to the maximum periscope depth.
If the periscope angle is other than zero on firing, it
will automatically swing to, and lock on zero. The
rest of the display also locks until a torpedo strikes
home, or until all have run themselves out.

Additional Dangers
There are aircraft hunting for you. If one is spotted,
you will hear it approach and your klaxon will
sound. You have about two minutes to dive below
30 ft.; if you fail you will be sunk.

If you spend some time dead ahead of the target
submarine it will torpedo you.

When the game is first loaded you will be offered a
quick practice shot at a sitting target. Follow the
prompts on the screen exactly to make use of this
option.



(c) 1983 PROTEK COMPUTING LTD.



Summary of Controls

Key                        Function
5 (<-) or Joystick left    Rudder left
6 (v) or Joystick back     Hydro-planes down: dive
7 (^) or Joystick forwards Hydro-planes up : surface
8 (->) or Joystick right   Rudder right
A                          Abort salvo
B                          Blow ballast
C                          Go to Chartroom
E                          Change engines
F                          Fire second and
                           subsequent torpedoes
I                          Turn periscope anti-
                           clockwise by 6
J                          Decrease engine revs
K                          Increase engine revs
N                          Flood tanks (negative  buoyancy)
O                          Turn periscope clockwise
                           by 36
P                          Raise/lower periscope
T                          Prime torpedoes and fire first torpedo
V                          View through or exit from periscope
X                          Exit from Chartroom



------------------------------------------------------------------


HUNTER KILLER
-------------

DUAL GAME

Loading the Game
To play the dual game you need two ZX Spectrums,
both fitted with Interface 1 and their own TV sets.
They should be linked using the networking lead
supplied with Interface 1 as shown in Chapter 7 of
the Interface 1 and Microdrive Manual. Connect the
tape recorder to one ZX Spectrum and type in
LOAD "" or LOAD "HUNTER2" and load the
program in the conventional manner. The program
will autorun.

Type LOAD*"N";1;"HUNTER2" followed by ENTER
into the other ZX Spectrum; when the program in
the first computer runs it will transfer the program
to the second computer.

Playing the Game
The area of combat and the destroyer, mine and
seabed hazards are the same as the solo version.
All the submarine controls and instruments and the
hazards of running underwater are unchanged.

Apart from the fact that the target is now controlled
by the operator of the other computer, there are
two differences between the solo and dual games.
Firstly, the dual game has no air attacks, the duel is
between the two submarines only. Secondly, the
initial battery charge given to each submarine is
much less than in the solo game. This is to ensure
that each captain must conserve battery charge,
not just dive underwater and stay there indefinitely.

A summary of the submarine controls are given on
the back of this leaflet to let each captain have his
own copy.

If any error codes are generated, type CONTINUE
followed by ENTER. If all else fails, BREAK both
games and type in RUN2 to both computers. Press
enter together and the game will restart.



(c) 1983 PROTEK COMPUTING LTD.



Summary of Controls

Key                        Function
5 (<-) or Joystick left    Rudder left
6 (v) or Joystick back     Hydro-planes down: dive
7 (^) or Joystick forwards Hydro-planes up : surface
8 (->) or Joystick right   Rudder right
A                          Abort salvo
B                          Blow ballast
C                          Go to Chartroom
E                          Change engines
F                          Fire second and
                           subsequent torpedoes
I                          Turn periscope anti-
                           clockwise by 6
J                          Decrease engine revs
K                          Increase engine revs
N                          Flood tanks (negative  buoyancy)
O                          Turn periscope clockwise
                           by 36
P                          Raise/lower periscope
T                          Prime torpedoes and fire first torpedo
V                          View through or exit from periscope
X                          Exit from Chartroom
