Some of the rc Airplane guys take their antenna and coil them around a straw in leave them inside the plane
Can you do this with a RC car too??

I like the idea of not have that tube sticking up in the air.

you can but the range and signal quality isn't as good as if you had the antenna sticking out

If you own a 2.4 Ghz radio than it really wouldn't matter.

It doesn't work with a 75mhz radio. I've tried a few times.