Truck Stop included assault ramps for unloading people and vehicles from trailers, buses, and RVs. But what that supplement didn't include was a set of rules for actually driving off the ramp if the oversized vehicle was moving. Cars and cycles suddenly appearing from the back of a "lone" truck are a great way to fight off uninvited escorts.
There are two factors to be considered when you want to drive a vehicle off a ramp from a moving oversized vehicle to the roadway. These factors are the speed of the oversized vehicle and the orientation of the off-loading vehicle,
The speed of the oversized vehicle has two effects on the off-loading vehicle. These effects are the damage to the off-loading vehicle's tires and the difficulty (D class) of the maneuver.
Tractor-trailer rigs can have assault ramps only on the back of the trailer. Buses can have ramps out the front or back. Assault ramps are 1/2" long, Lowering a forward assault ramp lowers the vehicle's handling class by 2 for as long as the ramp is down. Lowering a rear ramp is not a hazard.
The off-loading vehicle will be facing either forward or backward relative to the oversized vehicle's direction of travel. If the off-loading vehicle is facing forward then it may off-load normally. If the off-loading vehicle is facing backward, but has a relative velocity of 20 mph or less, it may also off-load normally. But, if the off-loading vehicle has a relative velocity over that vehicle's maximum speed, or over 20 mph in reverse, then that vehicle may not off-load normally. The factors for normal off-loading are in the accompanying table.
At the beginning of a turn a semi-trailer drops its rear assault ramp. The rig is going 100 mph. On phase 7, Al, in his Killer Kart, accelerates to reverse 10 mph and back off the ramp. Al's speed is now 90 mph (100 -- 10). Since Al off-loaded at 90 mph, his tires take 2 dice of damage. He also drops his handling class by 7, putting it at -- 4. Al looks at the control table and sees that he needs a 6. He rolls a 3. Oh, well. Al rolls on crash table 1 (remembering his +3 modifier) and gets an 8. Poor Al, He flipped and burned.
Velocity of Off-Loading Difficulty Damage Car Relative to the Road of Maneuver to Tires 0-19 MPH 0 0 20-29 MPH 1 2 pts. 30-39 MPH 2 1d3 + 1 40-59 MPH 4 1d6 60-79 MPH 5 1d6 + 2 80-100 MPH 7 2d6