Lessons for New Drivers: 

Tips for Safely Navigating Curves

1 FHWA, Low-Cost Treatments for Horizontal Curve Safety 2016, 

FHWA-SA-15 084, USDOT, Washington, DC, 2016. 

WHAT ARE ROADWAY DEPARTURE CRASHES?

A roadway departure (RwD) crash is one in which a 

vehicle leaves its lane by crossing an edge line or a 

center line, or otherwise leaves the road.

WHY IS IT IMPORTANT TO REDUCE RwD CRASHES?

RwD crashes account for 87 percent of curve-related 

fatal crashes. While the majority of these involve vehicles 

leaving the roadway and striking roadside objects such as 

trees and guardrail, about 10 percent of them are headon crashes where vehicles wander across the center line 

of a curve and into the opposing lanes.1

Each year, approximately 25 percent of 

all roadway deaths occur on curves.

YOUR ROLE AS A NEW DRIVER

The majority of roadway departure crashes are 

preventable, but it takes attention and knowledge to 

avoid them. When approaching a curve, a driver will 

always have to turn the wheel and in many cases will 

have to slow down to stay in the lane and/or avoid a 

crash. Drivers seeing, recognizing, and reacting to 

certain aspects of the roadway and roadside plays a key 

part in helping keep their vehicles on the road.

WHY ARE CURVES PRONE TO MORE CRASHES?

It is important to be cautious and alert when driving 

through a curve. When a vehicle navigates a curve, 

centrifugal force increases the risk of the vehicle 

leaving the lane or road. If a car enters a curve, 

centrifugal force tends to keep the vehicle moving in a 

straight path, and not following the curved path (see 

figure 1). 

Source: Getty Images, Inc.

ROADWAY 

DEPARTURES

Figure 1. Physical forces affecting an automobile 

in motion. 

Source: Texas Department of Public Safety.

http://safety.fhwa.dot.gov
o Pavement markings refer to the yellow and white lines

that help drivers see their path as they approach a curve.

Pavement markings may also provide messages or

instructions, as shown in figure 2.

o Delineators are guidance devices on the side of the road

which indicate the alignment of the roadway.

o Chevrons (figure 3) are signs with arrows that point to the

right or left, depending on the direction of the curve.

ADVANCE WARNING. Figure 3 is an example of signs 

broadly categorized as advance warning. In general, when 

drivers observe warning signs in advance of a curved or 

turning roadway, that is an indication they need to slow 

down to safely drive through the curve.

Advance curve warning signs (Figure 3) show the type and 

direction of the curve ahead.

o Advisory Speed Plaques (figure 3) display the

recommended speed to drive through the curve.

Advisory speed plaques are often placed to supplement

a warning sign where the approaching speed is higher

than the speed that is safe for drivers to navigate

through the curve.

o Vehicle Speed Feedback system is a broad category that

provides interactive feedback to drivers based on current

conditions. For example, if a driver approaches a curve at

a higher-than-recommended speed, a speed feedback

sign (as shown in figure 4) displays the vehicle’s speed in

real time to alert the driver to slow down.

FHWA-SA-21-091

DriversEd.com – This website provides young drivers with online and in-car driving 

lessons as they prepare for their driving tests.

Pennsylvania Department of Transportation Driver and Vehicle Services – The 

driving manual for the State of Pennsylvania has a section that addresses how to 

negotiate curves.

Roadway Departure Safety – Federal Highway Administration (FHWA) – FHWA’s RwD 

safety web page provides information and resources that can be useful for anyone 

unfamiliar with this topic.

CONTACT

Joseph Cheung 

Joseph.Cheung@dot.gov

Figure 2. Delineation examples: pavement marking, 

chevron signs, and roadside delineation.

Source: Pennsylvania Department of Transportation Safety

Driver attention plays an essential role in making sure 

vehicles stay in the lane, whether it curves or is straight. 

The road cues include:

DELINEATION. This element includes several types, like 

the following which are shown in figure 2.

Figure 4. Dynamic speed feedback sign.

Source: Dwernertl, English Wikipedia, CC BY-SA 3.0.

Figure 3. Top row: three advanced curve warning 

signs. Bottom Row: Chevron sign and advisory 

speed plaque.

Source: Manual on Uniform Traffic Control Devices.