A lot of it depends on the truck and the driver. (And luck)
I have seen people jump over 15 feet high, 4 or 5 times in a row, no problems. I have seen people jump about 5 feet high, and break several things. I have a rc-solutions roll cage on my t-maxx with flex-tek a-arms, and man can that truck take a beating! I hit everything as hard as possible, and usually come out alive.
I highly recomend (like someone else did) is that you start off small. Start off with a little 1 foot (bike skate ramp) and just get used to keeping control in the air, and keeping your speeds consistant. Then work your way up. I have built (and have a how to) for a custom adjustable ramp that you can set the angle and height, and it's a great way to learn. Practice makes perfect. I know people that call pull a backflip or a double and land it 99% of the time, because they know their truck, and have good control.
Brian
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