check your throttle trim!! and you really shouldnt start any rc without the transmitter and the reciever on because it could cause alot of damage.. but you check your trim and if that isnt it unhook your linkage and realign it to idle when it should idle and go when you hit the throttle.
Just for future reference, NEVER start it without making sure that the servos are responding properly. Not even a fail safe will save it if it's not turned on.
i nearly totaled my jato like that it took off on my and smoked a cast iron fence at wot wont make that mistake again, always turn your transmiter on first and off last