Ive decided to take back out my K'nex coaster building sets and begin building a new coaster- K'neXLC. It will be a working k'nex coaster in the style of the late Hypersonic XLC. It will not actually have an air launch, but I am planning to experiment with launch types.
I am still unsure of the complete dimensions, but I am planning for it to be about 4-4.5 feet tall with a launch track about 5-7 feet long.
I am using a Screamin Serpent train
http://www.wired.com/images_blogs/photo ... oaster.jpg
The launch system will most likely include a catch car (piece of lift chain) hooked to a cable (string or wire).
Pictures on the NLDC page;
http://www.NoLimitsDevCenter.net/p5790
If anyone has any ideas for launch, brake, or other construction, don't hesitate to tell!