No, there is no helicopter that you can fly in GTA 3 game, and also there is no cheat for spawning helicopter. At the airport, you will see many helicopters but all of them are like statues ( frozen helicopters), no one is for flying. Even you can’t move that particular helicopter from its original place by using a bomb or by doing any method.
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If you have to fly something, then you can fly an airplane inside GTA 3 game, the name of that airplane is – dodo.
You can fly a dodo airplane, if you want to fly, then click here.