Some Improvements to Arduino

Some improvements to Arduino that I see just from looking over the images are the following:

Provide vehicle shells that will protect the Arduino circuitry. The vehicle shells could be created using 3-D Printing so that an exact fit around the circuitry occurs.

If you do not know what 3-D Printing is 3-D Printing is a process where an image is rendered in a 3-D graphics program such as Blender and is then created using the same type of layering affect that a copier uses to build its image. Various layers of material are built upon each other to bring the 3-D image into the real world.

3-D can be used to create anything that your Arduino project needs.

Also I have not seen any type of vehicle design related Sketches that would include using Arduino for model airplane components such as servo, rudder or landing gear accuation.

Are there any Sketches that Arduino has that could be used to operate a remote controlled planes mechanical functions?

Also does Arduino manufacture boards that can be waterproofed so they can operate in wet weather?

Various companies make enclosures for Arduino boards.
I personally use plastic boxes that are suitable for my end use, from plastic pencil boxes to boxes with latches for the cover from Really Useful Boxes, both of which I found at Staples. You can see pictures in the link at my signature.
I don't think there is any standard box as every design tends to need some kind of IO connector to the outside world.

For 3D printing, there is a program called RepRap I think where you can build & then program a 3D printer, creating your 3D design from layers of melted plastic as you describe.

If you want waterproofing - the problem is always in the connector. You can get spray-on polyurethane in a can to act as "conformal coat", I have seen just plain nail polish used also. How to waterproof the connector tho? Best bet is to enclose the electronics in a sealable box, and you just have to deal with sealing the cable thru holes, and you obtain waterproof feed thru connectors for that.

dryson:
Are there any Sketches that Arduino has that could be used to operate a remote controlled planes mechanical functions?

Check out the ArduIMU project (http://store.diydrones.com/ArduIMU_V3_p/kt-arduimu-30.htm) such as Google Code Archive - Long-term storage for Google Code Project Hosting.
There are also (many) others.

Also does Arduino manufacture boards that can be waterproofed so they can operate in wet weather?

Plug in all things you need plugged in. Put a smearing of ScotchKote or acrylic conformal coating over it. Done!
Or use a weatherproofed enclosure, like an OtterBox (Small waterproof OtterBox [1000] : ID 340 : Adafruit Industries, Unique & fun DIY electronics and kits).