IMPORTANT NOTE: THIS CALCULATOR WAS UPDATED ON 9 NOV 2022 TO USE A HORIZONTAL LENGTH (L) TO SIMPLIFY THE MEASURING PROCESS.
The Approach Angle calculator computes the maximum angle (α) of a ramp onto which a vehicle can climb from a horizontal plane without interference (scraping) the ramp or incline.
INSTRUCTIONS: Choose units and enter the following:
ANGLE (α): The calculator returns the approach or departure angle in degrees. However, this can be automatically converted to other angle units (e.g. radians) via the pull-down menu.
You own an RV and want to take it up your driveway, but you DO NOT want to hear the crunch of bottoming out. The Approach Angle calculator computes the maximum angle your vehicle can approach based on two measurements, the height at the tail (H) and the length from the tire contact point and the point below the tail (L)
The formula for the Approach Angle is:
α = tan-1(H/L)
Approach angle (α) is the maximum angle of a ramp onto which a vehicle can climb from a horizontal plane without interference. It is defined as the angle between the ground and the line drawn between the front tire and the lowest-hanging part of the vehicle at the front overhang. Approach angle is also referred to as ramp angles.
To calculate your approach angle, put your vehicle on a flat and level surface. Next, measure the height (H) and length (L). To measure the height (H) and length (L), mark the point directly below the end of the undercarriage at the tail of your vehicle. Measure the height from the undercarriage to that point, and the length from the center of the tire to that point. This only works if there is nothing (e.g., muffler tail pipe) that hangs down even lower. α° = Approach angle: ß° = Departure angle
Break-over Angle (β )
Camber Angle (Φ)
Wikipedia - http://en.wikipedia.org/wiki/Approach_and_departure_angles