TWIRLYBIRD

By Chris and John Goodman

Program contents, audio-visual work,
documentation, and packaging
© Copyright 1984

Hardwood Software
4390 Provinceline Road
Princeton, New Jersey 08540

THE PHONEY-BALONEY STORYLINE BEHIND IT ALL
The subgalactic ice colony of Dyrinotron has been attacked for centuries by the . . . the . . . oh, the heck with it. Those silly stories never made much sense anyway. Besides, you could probably come up with one twice as good as any we could, so why don't we just get right to the important stuff?

You are now the pilot of a RED MANTRA helicopter. What? You don't know the first thing about flying a helicopter? Well don't worry. ..this one's mostly computerized. We'll get to the actual operation of the helicopter in a bit. Perhaps first we should explain your mission.

The RED MANTRA is equipped with regular bombs and special, high intensity bombs called PENETRONS. Since these are much heavier than regular bombs, your helicopter can only carry five at one time. Use them wisely!

Your main objective is to destroy all of the enemy's vents, which are scattered over a large territory, by dropping PENETRONS down them. Why? Well aside from saving the universe, you'll be saving your own skin, because the vents are exuding TROXALINE -- a gas which has a tendency to make metal objects like your RED MANTRA dissolve. Sure, you've got a little time before its concentration becomes high enough to do any damage, but the enemy's surface defenses will keep you hopping. And your Twirlybird can run out of fuel if you aren't careful!

BASIC CONTROLS AND OPERATIONS
Your helicopter is controlled through joystick 1, as in the diagram below.

accelerate
^
  rotate left < • > rotate right
v
decelerate

Diagonal directions will activate both adjacent functions; for example, pushing up and to the left will simultaneously rotate the helicopter left and accelerate it. The button fires either a PENETRON or bomb (see below). You can fire one or two at a time.

For ease in navigation, propulsion is always provided in the direction the RED MANTRA is pointed. Although it is fairly light and maneuverable, don't expect it to stop on a pinhead!

Altitude is controlled by three adjacent keys on the keyboard: "A", "S", an "D". "A" stands for ascend, "S" (or stop, and "D" for descend. Once put at a certain height, the automatic altitude control will keep the helicopter precisely there. The RED MANTRA can fly at any altitude between II and 250. Although it will land when the altitude is zero, if you attempt to move while at this height, the helicopter will tip over and crash!

Two other keys are used on the keyboard. "P" toggles between PENETRON and regular bomb modes. When in PENETRON mode, the word PENETRON appears in inverse at the bottom of the control panel. The SPACE BAR freezes/restarts the action if you need to grab a bite to eat, wipe the sweat off your face, or what have you.

THE CONTROL PANEL
The control pane! displays information vital to your survival, so don't forget to look at it once in a while!

Starting in the upper left, we first see DAMAGE : TELF. The RED MANTRA has its share of armor, so it probably won't go down in a fiery blaze after one hit. 'Various systems aboard, however, can be damaged or destroyed. The current condition of the four main systems are displayed by color: GREEN indicates a .working condition; YELLOW indicates a damaged condition; and RED indicates (you guessed it) that it has been destroyed.

T stands for TAIL ROTOR. If the TAIL ROTOR is damaged, you will be unable to rotate in one direction. If the TAIL ROTOR is destroyed, you won't stay aloft for very long.

E stands for ENGINES. The RED MANTRA gets forward propulsion both from the tilt of its MAIN ROTOR (like most helicopters) and from high-power booster engines. If the engines are damaged, you will find yourself crawling at a miserable pace! They can only be destroyed, though, if the entire helicopter is.

L stands for LAUNCHERS. Since they are on the bottom of the helicopter, they are particularly vulnerable. When damaged, you will be able to fire only one bomb or PENETRON at a time; when destroyed, you won't be able to fire at all! Probably a good time to get them repaired!
Finally, F stands for FUEL TANK. After it is damaged, notice how quickly your fuel indicator (see below) goes down as fuel spills out!

On the upper right is the fuel indicator. Fuel that you have left is displayed as a row of vertical bars. 16 bars indicate maximum fuel capacity; a bar is removed every time your fuel falls by 1/1 6th. When your fuel level is below 1/4, the indicator bars turn red to alert you. Directly below the DAMAGE display is your altimeter. It ranges from 0 (on the ground) to 250 (maximum altitude).

Next to the altimeter, on the right, is CONC.: 000. This stands for concentration, and indicates the concentration of TROXALINE in the outside atmosphere. As it begins to creep into the 900's, start worrying! If it reaches 999, the game will end after the gas dissolves your helicopter (and also your reserve copters on the ground!) Unfortunately, the only way to stop the gas is to destroy every vent.

The red window below the top control panel is used to display messages. The computer will alert you in this area when you receive damage, forget to land at the base, or otherwise mess up. It also displays messages when various other situations occur.

THE BOTTOM CONTROL PANEL
Your score is displayed in the bottom left. Points are awarded for destroying the enemy's defenses. See the descriptions of the specific defenses for point values.

To the right of your score, you'll see some small helicopters, which, of course, represent your reserve RED MANTRAS. At 50,000 points, your exceptional skill will be rewarded by the addition of another helicopter.

Next, on the right, is the number of PENETRONS your copter is currently carrying. When the word PENETRONS is displayed in inverse, you are in PENETRON mode.

On the far bottom right, is the level indicator. If you car, destroy all the vents before the concentration reaches 999, you'll advance to the next level, which is a bit tougher.

YOUR ENEMIES (AND OTHER OBJECTS)

THE BATTLEFIELD
You are battling on a large landscape that extends approximately 3 screens horizontally and 6 vertically. You cannot fly beyond the borders of this area (but feel free to try anyway). Each new game and round is set on a different and random field (with the exception of your base, which is always in the same place.)

RED MANTRA
This is the red object that looks like a helicopter and can fly. You can control it.

YOUR BASE
Your base is a small collection of various structures. !t will always appear at the top left of the battlefield. Its most important structure (aside from the video arcade) is the landing pad. This is the only place that you can land and get your damages repaired, obtain a full supply of PENETRONS and fuel, etc. The pad is surrounded by an energized barrier that you cannot fly over; the only entrance and exit to the pad is from the bottom.

TREES AND BUSHES
Although the planet is cold and icy, a strange variety of vegetation does thrive. These trees and bushes are not particularly useful, although TANKS (see below) cannot crawl over their iron-hard trunks and must detour around them.

VENTS
A VENT appears as a large, purple circular object with a hole in the center. You must make a direct hit with a PENETRON down the hole to destroy the vent and score 2000 points. But don't fire a regular bomb down the vent! It will only cause it to exude TROXALINE at a faster rate.

TANKS
Tanks are light blue, round objects. They move fairly quickly, although the RED MANTRA, when its engines are working, can easily outrun them. As has been noted, they cannot move over trees. Their main threat is that they can shoot bullets at you (lots of 'em!). And the altitude of the bullets, thanks to an automatic ballistic guidance system, will always match your altitude. In other words, a bullet that is headed for you will almost never go under or above you. You'll have to do some fancy maneuvering at times, but that's why you're the pilot! You'll receive 750 points for each tank you destroy.

HYPERIONIC GUNS
Hyperionic Guns, more commonly referred to as BAZOOKAS, will also attempt to blast you out of the sky. However, unlike the tanks, the guns cannot move. Also, they are heavily armored. It takes 2 or 3 direct hits to destroy one. Luckily, their guidance systems can be knocked out by destroying the network of radar dishes on the surface. If this is accomplished, they will no longer be able to aim (but can still fire!). You'll get 500 points every time you hit a bazooka.

RADAR DISHES
These dishes are the heart of the BAZOOKAS' aiming ability. Each one is worth 1000 points. Destroy them all to cripple the guns and earn a hefty bonus of 5000 points!

LASER PADS
These triangular pads are deadly if flown over. The emitted beam is so strong that you should consider yourself lucky if you escape with only damage! They can be destroyed, though, for 600 points.

MISSILE SILOS
Missile silos are round areas recognizable by their dancing guidance lights. Like the laser pads, they should be avoided if possible! Flying over one will almost certainly earn you a bit of damage. Since most of the system itself is underground, missile silos cannot he destroyed, even with a PENETRON.

FORCE FIELD WALLS
Flying over one of these walls usually proves injurious to your bomb launchers, as the force field wrenches them right off the bottom of the RED MANTRA. However, the force extends up to a height of only 150, so if you are above this altitude, you can safely cruise over them to your heart's content.

SCOUTS
These tiny vehicles crawl over the surface from vent to vent. If hit, your fuel tank will be miraculously filled to the brim (don't ask us why!) You'll also earn 50 points. In addition to their erratic movements, scouts will occasionally disappear down holes you can't see, so you must be fast!

PLAYING THE GAME
After pushing the START key to (what else?) start the game, you find your copter inside your base. You anxiously ease her out, only to crash immediately. Sheepishly, on your next copter you push "A" to get some altitude before moving.

A word should be said about altitude here. Due to their mechanisms, bombs and PENETRONS will not detonate at any altitude below 25, and only rarely below 50. So, for the most part, you're going to be above this altitude. However, the higher you fly, the greater your firing ability must be to hit ground targets accurately and the longer your projectiles take to hit the ground. You'll probably find a comfortable height somewhere between 75 and 150, unless you constantly fly into walls, in which case you'll probably want to fly somewhere above 150.

So along you go, skirting deftly around laser posts and missile silos. There's the vent just ahead ... but watch out! There are two tanks cruising next to it. You quickly accelerate and curve to the left. dropping a bomb when you feel you're in the right position. Down it streaks, and one of the tanks explodes in a fiery flash! But the other fires as you go by, and damages your fuel tank. Gritting your teeth, you circle back and demolish it. Slowing down, you ease a PENETRON into the vent and watch as it explodes and disappears. Off you go to find the next one, and almost hit a force field wall. Gotta watch out, you think, and bomb a few radar dishes. A message catches your eye, and you discover that your fuel is almost gone! Luckily, there's a scout nearby, so you spin around and drop a couple of bombs. But they both miss, and the scout changes direction and moves away. Quickly you zoom past it, turn and fire another quick two ... but they miss again and it's almost too late. Frantically, you start to head for your base, but before you've gotten halfway there, you run out of fuel, spiral down, and explode.

And so it goes. Practice may not make perfect, but after a few hours of flight, you'll begin to complete more and more levels, until you can truly call yourself a Twirlybird Pilot.

DISCLAIMER AND LIMITED WARRANTY

However, to the original purchaser only, HARDWOOD SOFTWARE warrants that the medium on which the program is recorded will be free from defects in materials and faulty workmanship under normal use and service for a period of ninety (90) days from the date of purchase. If a defect in the medium should occur during this period, the medium should be returned for repair or replacement to HARDWOOD SOFTWARE or to its authorized dealer. After this period, HARDWOOD SOFTWARE shall have no obligation to repair or replace damaged software.

NOTICE: Upon receipt of this computer program and associated documentation, HARDWOOD SOFTWARE grants you a non-exclusive license to execute the enclosed software. This software and documentation are copyrighted. You are prohibited from reproducing, translating, or distributing this software in any unauthorized manner.