I used to repleace filepath to finish my mod
but this time it seems too hard to me
I just don't know how to make a mod from begining to the end...
could anybody help me?

As far as i know. It is easier to make a helicopter fly if its side view.

I'm not really understanding the problem. Is there an error? Are you sure the image is in pallete, inside the .rte, and the filepath is correct? I'm attaching a mod I made a while back that has two helicopters, maybe looking at the codes can help you out some.

AFAIK false.

Firstly: Damn that is nice sprite.
Secondly: You can essentially make it a drop ship with one engine, placed directly above it. Have a look at the drop ship's coding, and some other dropships. there's no real easy way to do it, especially since you have to make gibs afterwards ( )

also Re: AFAIK blah blah, depends on your approach as to how easy it is to make something. If you want to go about making a helicopter the same way nachos did, then you're better off with it facing the side, however if you want it facing forwards you can end up with something along the lines of darlos' VTOL thing. Don't just say "nah you did it wrong" if you haven't actually got much experience in implementing actor designs in CC. There is always a workaround, and it's usually fairly simple.

Jesus, implementing is like, my most used word of the month. Must be related to http://i50.tinypic.com/33nxgqv.png or something.

Thank you all at first
the good news is that in you approach I fly the helicopter
Now My helicopter serves as a drop ship
To make it balanceable,I adds two engines on each side with the sprite of null.bmp.
So the engine is invisiable
I also adds a actor on a side of helicopter which have a Gatling Gun(just like the helicopter in Call of duty 4)
So my helicopter is an armed one
In other words I have done a small process.
But the problem is I can't control both the actor and the helicopter
Every time I control my actor to shot heigher aims the helicopter flys down to low height(you can try with all your drop ships)
I don't if it is the AI makes it so...
So I need a lua script(I think lua script is the best way) to let my helicopter stay in origin position when I am not in control of it.

That's because dropships are automatically set to hover at a set height when set to stay. There is of course a Lua solution, ask mail or Duh, they can direct you to good Lua scripters. Otherwise there is also Darlos9D's hover code, ask for permission or credit him for it if you want to use it.

PS: Darlos' hover code so far has been tested only on ACrabs. Caveat.