Hi
I'm not certain which noises you're referring to (I haven't heard aeroplane for ages, and only remember there being a fairly normal slap solo in it...), so I'm not sure I can help - if you ask in either techniques or recordings, you might find someone who knows...
As for weird sounds with an un effected bass - there are loads - just experiment with pulling the strings of the side of the neck, attaching pegs to the strings, fretting the strings onto the pickup, squeezing two strings together and fretting them with the same finger, detuning the strings til they rattle like mad, and then all the usual stuff like slapping, tapping, strumming etc.
have fun!
Steve
www.steve-lawson.co.uk