During the first title screen, push the D-button UP, DOWN, LEFT, RIGHT and push button 1. Repeat this sequence again in the 2nd title screen and push and release button 1 quickly. A screen appears in which the stage numbers rotate automatically. Push the button when it comes to the stage of your choice.
In stage 1, shoot the air-mines coming out of the ground after the first barrack. After you destroy 20, the hostages run much faster. This trick also works in stage 4 (and in similar stages thereafter).
The screen edges overlap in Choplifter, so if you face the right and shoot, the bullets go
off the right edge and appear at the left edge of the screen, destroying anything there,
for example, the otherwise-hard-to-destroy gun turrets on some of the ships in stage 2.
Position your helicopter so the target is barely off the edge of the screen, face the other
direction, and shoot.
If you stay on the ground too long while picking up hostages, a tank will appear and begin shooting them. It is therefore a good idea to "bounce" the helicopter after landing. (Bomb a tank while hostages are on the screen to make them jump up and down and wave.)
Fly through the caves of round 3 backwards. You will be flying at the scrolling edge of the screen. A volcano must be completely on the screen before it will erupt. By flying backwards, you ensure that you have already flown over the volcano before it can erupt.
In round 3, be aware that air-cushioned vehicles occasionally appear at ground level. When dropping off hostages, keep an eye open for enemies flying along the ground. (They will always come from the left side of the screen.) Turn the helicopter to face left before you land, and you may be able to shoot enemies down before they have a chance to fire.
Try to bring back 16 hostages each time you return to headquarters to maximize the points earned. After you have rescued 32, pick up only 8 for your last trip back to headquarters. If you get shot down, this will minimize casualties and leave the other 8 hostages alive so you won't have to fight your way to the last barrack.
When your helicopter is shot down with hostages on board, hold the D-button in either the up or down position, and rapidly alternate pressing buttons 1 and 2. One by one, the dead hostages are counted "safe". Note, however, this trick works only as long as your helicopter is falling. You will probably not have time to save more than three hostages before your helicopter hits the ground. You may be able to save an extra hostage or two by alternately pressing the D-button up and down, instead of holding either direction, but this is much more difficult. You're better off to practice avoiding enemy fire.
