[section=What is this?] This is a skip that allows you to skip half of the helicopter fight sequence.

[section=How-to] To do this skip, you must begin shooting at the first helicopter in the sequence. After a few shots, there should be another helicopter that goes into view.

Right about now, fire your rocket using right click, this should take out one of the 2 helicopters. After that, dive into the other helicopter until you begin losing health. Keep ramming into the helicopter until you and the other helicopter die and fall off-screen. The desert cutscene should now be playing.

[section=How this works*] After some brief testing and observations, I believe this works because the game checks if there are any helicopters left on the screen (or any that exists) before determining if the cutscene and level transition to the Desert chapter plays or not.

Every time you pass a wave of helicopters, the game will spawn more helicopters until it spawned the maximum amount set in the game. If the game tries to spawn more it will be unable to, and ultimately end the stage and trigger the next chapter.

If you die and only killed one out of the 2 helicopters then the game determines that you have failed, but if you die and cleared the first wave of helicopters then the game won't going to spawn any more because you are dead. And if the game can't spawn any more it will automatically think that you have finished the stage.

*This is just a guess through experience and observations and probably not how it works. But this is the best answer I can give to this skip.

Confirmed working in Games Collection version - wdaemon