Bad Piggies Modifications - #2: The Rotor Testing

Helicopters usually have one rotor.
But what if I modify it to two rotors or even a helicopter extension?
There are 3 different modifications (and a bonus) here.
1. One rotor (standard helicopter)
2. One rotor (helicopter extension)
3. Two rotors
Bonus: King Pig added
Episode 3 is next week... :)