Jump and run like a girl (no offense to the actual girls)

i had a similar event happen to me once
we were gonna take the family out of town, and i was getting the trailer ready and my dirtbike loaded onto it

my driveway had a slight slope to it, and i had put a piece of wood in front of the nosewheel to ensure the trailer stayed put

i had the trailer (just a little 5x8, single axle type deal) back into my driveway, so i jumped on my dirtbike and simply rode it onto the trailer
as soon as the bike hit the ramp, there was some weight transfer that lifted the nosewheel over the block of wood and the whole thing started rolling down the driveway and towards traffic (and this was not a quiet street i lived on)

it took me about 2 seconds to decide to drop the bike, jump off and grab the trailer in an attempt to stop it before it hit the street

of course, we're talking about 3-400 pounds here, i can stop that

in the origenal version, all you can do is hope whatever the truck hits isnt too expensive