First you need to know what the problem is. For routene issues there are procedures in the Maintenance Manual. For unusual problems, such as a hole in the skin, you can contact the manufacture's engineering department for a specific repair. There are also maintenance manuals for the components on the aircraft as well as the structural members of it.
In my area they often use them to repair power wires
To repair a primary blade of a Double Horse 9053 Volitation RC helicopter, first, carefully remove the damaged blade from the rotor assembly. Inspect it for cracks or breaks; if it's minor, you can use super glue or epoxy to bond the pieces together. For significant damage, it's best to replace the blade with a new one. After repairs, ensure that the blade is securely attached and balanced before testing the helicopter.
A purple helicopter is a helicopter of the color purple. Really?
There really arent any helicopter "powertrain" mechanics. In the USA the way it works is you earn an Airframe, Powerplant or Airframe and Power Plant licence (A&P) from the FAA (www.faa.gov). Once you have that under your belt you can get a job in the industry with a helicopter operator or at a repair station. Pay ranges from $20K/yr to $100k/yr.
Everybody I know says A helicopter.
For the helicopter body to be in balance and direction to steer the helicopter.
A helicopter pilot flies a helicopter in the army.
It depends on how much damage you are willing to inflict on the Helicopter, because many techniques can damage the Helicopter and be expensive to repair. If the Helicopter is still working, you could attempt to fly it out of the tree, though this could significant damage to the blades, and the body on impact if the Heli can't stay aloft. You could try getting a ladder, if that does not reach it, maybe a few brooms taped together could get it free. You could even try to climb to tree, if it is possible.
For a longer lasting repair and totally water proof use outdoor UV rated "helicopter Tape" or as its now known as 'surface guard tape". Make sure you get the UV rated type. I used 3" wide UV rated helicopter tape to repair a severe open crack on a dual dome skylight. The tape kept the water out for almost a year until I finally got around to replacing the dome. If you doubt the strength of this type of tape , the name comes from the fact it is used to protect the leading edge of helicopter blades from nicks and scratches. Now this tape is used on race cars etc.
Helicopter pilots do
In their helicopter.
There is no helicopter.