What Do Approach, Departure, and Breakover Angles Mean?

Off-roading is completely different from city driving. Say goodbye to flat roads and low speed bumps and say hello to uneven terrain and steep inclines. To conquer the wild, however, you’ll have to understand three important aspects of your vehicle: its approach, breakover, and departure angles.

What Is Approach Angle?

When driving up a hill, one of the most important things to consider is your vehicle’s approach angle. Approach angle refers to the steepest angle your vehicle can climb with no problem. If you try to climb a hill with an angle that exceeds your approach angle, you’re likely to hit your front bumper on the incline.

Factors That Affect Your Approach Angle

If you want to drive up steep hills, consider some of these factors that can influence your vehicle’s approach angle:

Vehicle Nose Length

Does your vehicle have a long nose or a protruding bumper? Because if it does, then you’re more likely to hit a steep incline. Vehicles with a long nose or long front overhangs (the length of the part of the body that extends past the center of the wheels) tend to have a smaller approach angle. Meanwhile, those with a shorter nose can typically climb higher inclines better.

Tire Size

Small, low-profile tires tend to reduce your vehicle’s approach angle. This is because you’re much closer to the ground. On the other hand, larger tires can lift your vehicle further from the ground, granting you a steeper approach angle.

Suspension

A higher approach angle is one of the reasons why most off-road vehicles have a lifted suspension. A vehicle with a suspension that lifts its chassis higher off the ground can improve its approach angle.

Front-mounted Winch

A winch that’s mounted on the front bumper will most likely reduce your vehicle’s approach angle.

Calculating Your Vehicle’s Approach Angle

To calculate your vehicle’s approach angle, you’ll need to know its ground clearance and the distance between your front tire and the edge of your vehicle’s nose. Here’s the formula:

• Approach angle = tan⁻¹(ground clearance/distance between tire and vehicle nose)

You can also use an approach angle calculator online.

What Is Breakover Angle?

Also known as the ramp over angle, the breakover angle determines the maximum height of a ramp or peak you can drive over without hitting the underside of your vehicle.

When off-roading, you never know how steep bumps on your pathway can get. As much as possible, you’ll want to avoid driving over any that exceeds your vehicle’s breakover angle.

Factors That Affect Your Breakover Angle

Here are some factors that can affect your vehicle’s ramp over angle:

Ground Clearance

Contrary to popular belief, breakover angle and ground clearance are not the same. However, ground clearance can affect your vehicle’s breakover angle. Vehicles with a high ground clearance tend to also have a high breakover angle.

Wheelbase

Another factor that affects your breakover angle is your vehicle’s wheelbase or the distance between the centers of the front and rear wheels. The longer the wheelbase, the lower the breakover angle.

Suspension

Similar to its effects on your approach angle, a lifted suspension can also improve your breakover angle.

Tire Size

Because larger tires add to your vehicle’s height and ground clearance, they also add to your breakover angle.

Low-hanging Components

Any low-hanging parts installed on your vehicle’s underside will lower your vehicle’s ground clearance and breakover angle, so you might want to detach them before going on your trip.

Calculating Your Vehicle’s Breakover Angle

To calculate your vehicle’s breakover angle, you’ll need to know your vehicle’s ground clearance and wheelbase. Here’s the formula:

You can also find several breakover angle calculators online.

What Is Departure Angle?

Opposite your vehicle’s approach angle is its departure angle. This angle determines how steep of an angle your car can climb without hitting your rear bumper against the ground.

Imagine a line drawn from the rear of the back tire to the lowest point of the car’s rear. The angle between this line and the ground is your vehicle’s departure angle.

Factors That Affect Your Departure Angle

Your vehicle’s departure angle depends on several factors, such as the following:

Rear End Length

A vehicle with a longer rear end typically has a lower departure angle, while a vehicle with a shorter rear end will have a higher departure angle and climb steep inclines much better.

Rear Tire Size

Small tires that keep you closer to the ground reduce your vehicle’s departure angle, while larger tires give you more clearance.

Suspension

It’s the same concept with your approach angle: a lifted suspension with a higher chassis improves your departure angle. Meanwhile, a lower suspension will greatly reduce it.

Tow Hitch

A tow hitch mounted on your rear bumper will extend the length of your rear end, which means it can also reduce your vehicle’s departure angle.

Calculating Your Vehicle’s Departure Angle

Calculating your vehicle’s departure angle is similar to calculating the approach angle. Here’s the formula:

• Approach angle = tan⁻¹(ground clearance/length of the rear end)

You can also find several departure angle calculators online.