Classic Computer Magazine Archive COMPUTE! ISSUE 43 / DECEMBER 1983 / PAGE 98

Nightflyer

David J. Bohlke

You have just assumed control of a light plane in the dead of night, and all you can see is your glowing instrument panel and the faint runway lights in the distance. Will you be able to safely land the plane? Yes, but you'll need pin­point control and some tricky maneuvering. Written for the Atari (joystick required), and Apple version (joystick or paddles) is included.

"Nightflyer" is a flight simulation game in which you control your joystick to land your plane. It's night and all you can see are your instrument panel and the distant lights of the runway.

To begin, you will need a joystick in Slot 1 of the Atari. The instructions will ask you to pull the joystick down for a Standard start or push it up for a Random beginning. The Standard start will position your plane on the glide path 20000 feet from the runway with an altitude of 1200 feet. The Random start will be more difficult as both distance and altitude will be randomly assigned.

Successfully landing your aircraft takes careful navigation. "Nightflyer," Atari version.

Reading The Instrument Panel

For a safe landing, you'll have to quickly and accurately interpret your instrumentation. The dial on the left center of the screen shows your velocity. Straight up is zero, and the marker at 90 degrees right is the 80 mph indicator. If your velocity dips below 80 mph before you touch down, the plane will stall and crash.

Below the velocity dial is a distance dial with a distance (DS) digit readout. After touchdown, this readout will reset to indicate the distance to the end of the runway.

On the right center of the screen is your glide path dial. You are on the glide path when the orange line is in between the two markers. Below this dial, on the lower right, is an altitude dial with a digital readout (AL) right underneath. Your altitude must remain above 30 feet before you reach the end of the runway, or else you'll crash into the runway lights.

There are three other digital readouts on the bottom of your panel. The delta velocity (dV) digit indicates the rate in mph at which your velocity is changing (5 to -5) each second. The delta altitude gauge (dA) tells your rate of descent or ascent (-25 to 25) in feet per second. On touchdown, your rate of descent cannot exceed -4 feet per second or your landing gear will collapse. There is also a time gauge (T) to indicate how long you have been at the controls.

After Touchdown

Once you touch down, you must stop the plane before you reach the end of the runway. For the quickest stop, make sure the dV gauge is at the minimum (-5). Your stick has four feather controls. Push it up or down to increase or decrease your rate of descent (altitude). Push the stick left or right to decrease or increase your velocity.

When you successfully land, you'll be given a score to evaluate your flight. This score is based on the time it took you to land the plane; your ability to hold it on the glide path; and the distance to the end of the runway once you've stopped. If the plane is above or below the glide path, points are deducted from your score; so it is possible to accumulate a negative score.

It may take you several flights to become adjusted to the control and instrumentation — but with some practice you'll soon be flying for a high score. Scores in excess of 2500 are exceptional.

Apple Version Notes For Nightflyer

Kevin Martin, Editorial Programmer

The Apple version of "Nightflyer" requires either game paddles or a joystick. If you are using paddles, control the plane's altitude (delta altitude or dA) by turning paddle 1. Likewise, control the plane's velocity (delta velocity or dV) by rotating paddle 0. On the other hand, if you use a joystick, follow the directions provided with the Atari version.

Landing the plane successfully takes practice and is quite challenging. Be sure to carefully read the details in the article on landing and scoring. To score the most points, you must touch down safely and stop the plane before you reach the end of the runway. Your overall score is based on the time of flight, your ability to hold the plane on the glide path, and the distance you are from the end of the runway when the plane stops.

The program sets up a crash sequence on the second high-resolution graphics page (line 1). The text and second high-resolution screen are first cleared. Then, using two POKEs, program control is transferred to the blank text screen so that you don't see what is being plotted. Later on, if you crash, the program quickly flips between the two high-resolution pages to simulate the crash (lines 520 – 526).

The sound routines for Nightflyer are POKEd into memory in line 2. The program stores the frequency of the sound in location 769 and its length in location 768. This routine produces the random notes at the beginning and end of each play. It also provides the crash sound (line 515) and the sound that is heard when the plane touches down.