US Department of Transportation’s Vehicle-To-Everything (V2x) Communications Summit: Preparing for V2x Deployment

​​​​To understand the safety promise of V2X, we must first understand the magnitude of the problem we are trying to solve. Last year, nearly 43,000 people lost their lives on our roadways. The 2021 numbers represent the highest number of fatalities since 2005 and the largest annual percentage increase in FARS history. Recently released numbers from NHTSA for the first quarter of 2022 show this alarming trend continuing.  To solve big problems, we must be willing to work toward big solutions.

The Safety Promise of V2X

I believe that V2X is one of the most promising life-saving technologies available today. When connected vehicles talk to each other, they are transmitting data every 10 milliseconds such as GPS location, acceleration, predicted path, and driver controls such as steering input and braking. V2X applications harness this actionable, predictive data to improve safety on our roadways.

One NHTSA study estimates that V2X could address up to 80% of all crashes involving non-impaired drivers. This could save thousands of lives and prevent or mitigate millions of crashes every year. 

Most Wanted List

For more than 25 years, the NTSB has released its Most Wanted List of critical transportation safety improvements to call attention to the issues requiring immediate attention. Because of the significant safety promise of V2X, the NTSB added Connected-Vehicle technology to its 2021-2022 Most Wanted List. 

V2X – Additional Layer of Protection

Some outside this room may wonder why connected vehicle technology is necessary with the emergence and advancement of onboard sensors. 

The NTSB strongly supports sensor-based collision avoidance systems, but as some of the investigations I will discuss demonstrate, sensors, radar, and lidar have limitations such as line of sight, inclement weather, or an unexpected profile of a vehicle. 

Importantly, V2X is not intended to replace the current and future sensors on vehicles. Rather, we can merge onboard sensors with V2X technology to create redundancy and allow for greater confidence when an imminent crash prevention scenario occurs 

Safe Systems

The way we look at safety on our roadways has changed. To reduce deaths and serious injuries on our roadways, we must look at our transportation network holistically and design a system with layers of protection for all roadway users. Technology, and V2X specifically, play a crucial role in achieving our ambitious safety goals. As you can see from just a few of the examples on this slide, V2X applications can help address each element of the Safe System Approach. 

Connecting the vehicles on our roadways to each other and the infrastructure removes operational silos and allows for the development of countless applications that have the potential to mitigate injuries and save lives.

Imminent Crash Prevention

The use cases of V2X technology are broad and include non-safety applications including improved traffic flow and increased fuel economy, but the NTSB’s interest in V2X is specifically on imminent crash prevention and its promise to save lives. 

In 2015, one of the largest naturalistic V2X driving studies was conducted by Volpe as part of the Safety Pilot Model Deployment with approximately 2,800 V2X equipped vehicles. The intent of this deployment was to evaluate V2X technology in a real-world driving environment. One remarkable finding from this study was that there were no missed forward collision warning alerts—out of close to 400 rear-end crash scenarios observed, the V2X technology alerted the driver in all of them. 

Crashes often happen very quickly, so imminent crash prevention applications must rely on low latency, high reliability communication 

The potential for harmful interference impairs the accuracy and reliability of this communication and degrades the safety promise of V2X.

Throughout my presentation, I will discuss NTSB crash investigations in which the crash scenario may have been prevented by imminent crash prevention V2X applications 

The NTSB first identified the potential for connected vehicle technology to save lives in 1995 after an investigation of a crash in Menifee, Arkansas. 

Menifee, AR

It was January 1995 at 1:50 in the morning on Interstate 40. The lead vehicle entered dense fog and slowed their speed from 65mph to 35mph and was struck in the rear. 

Subsequent collisions occurred. The crash included 9 total vehicles and resulted in 5 fatalities. One surviving driver described the conditions as “white out” and said that he could not see the end of the hood on his car. 

With the limited line of sight and slowed lead vehicle, the NTSB first recognized the need for a collision warning system that was not limited by line of sight or inclement weather and recommended that the FCC to allocate spectrum to enhance the development of collision warning systems.

In 1999, the FCC allocated 75mhz of spectrum as part of the DOT’s ITS national program.

Chesterfield, New Jersey

Then, after more than a decade of development and validating research, the NTSB first recommended in 2013 that NHTSA require connected vehicle technology after an investigation in Chesterfield, New Jersey.

On February 16, 2012, at 8:15 in the morning, a school bus carrying 25 elementary school students was traveling north and stopped at the stop sign. At the same time, a dump truck was approaching the intersection from the east and did not have a stop sign. 

As you can see from the second picture, the intersection was obstructed resulting in limited line of sight. 

The bus driver failed to see the dump truck and proceeded across the intersection. The dump truck struck the side of the bus resulting in one fatality and 16 injuries.

The NTSB found Connected vehicle technology could have provided active warnings to the school bus driver of the approaching truck and possibly prevented the crash. Therefore, the NTSB recommended to NHTSA to require connected vehicle technology on all newly manufactured vehicles. 

Williston, FL

In 2017, the NTSB reiterated its recommendation to NHTSA after an investigation in Williston, Florida

In May of 2016, a combination vehicle was making a left turn from westbound US-27A across two eastbound lanes. A Tesla, traveling east, struck the right side of the combination vehicle at 74mph resulting in one fatality.

The NTSB found that the 2015 Tesla was equipped with both automatic emergency braking and forward collision warning, but the system did not detect the combination vehicle—and the system was also not designed to detect crossing path vehicles. 

Recognizing the limitations of onboard sensors to respond to crash scenarios outside its design capabilities and the potential for connected vehicle technology to fill that safety gap, the NTSB reiterated its connected vehicle recommendation to NHTSA.

As V2X applications continued to develop, it became clear that the safety promise of V2X extended to vulnerable road users and not just the cars and trucks on our roadways. Therefore, the NTSB released a 2018 safety study on Motorcycle Safety and a 2019 safety study on Bicyclist safety. Between the two safety studies, the NTSB issued six recommendations to incorporate vulnerable road users into the development of connected vehicle technology

Rochester, IN

In 2020, the NTSB reiterated its recommendation to NHTSA to require connected vehicle technology after an investigation in Rochester, Indiana 

On the morning of October 30, 2018, in Rochester, Indiana, a school bus was traveling north on a rural, two-lane road. The school bus stopped on the east side of the road to pick up 10 students from a mobile home park on the west side of the road. So the students were required to cross the rural road to board the school bus.

Conditions were dark, there was no roadway lighting, and there was a curve 900 feet up the road from the bus stop. 

A 2017 pickup truck traveling south at 58 mph struck four students crossing the road, fatally injuring three, and severely injuring the fourth. 

Once again, the NTSB determined that this crash scenario could have been prevented by connected vehicle technology and reiterated its recommendation to NHTSA.

After reiterating the NTSB’s recommendation to NHTSA twice and anticipating the impending regulatory upheaval, the NTSB added Connected Vehicle Technology to its Most Wanted List in April 2021

The following month, the FCC followed through with its NPRM and issued its final rule to reduce the available spectrum by 60%

In January 2022, I hosted a four-part V2X video series: Preserving the future of connected vehicle technology with guests from industry, academia, associations, and Federal and State Departments of Transportation. 

Interstate 70/76 – Mt. Pleasant, PA

Finally, in February of this year, the crash in Mt. Pleasant, Pennsylvania was the first opportunity the NTSB had to directly address V2X issues in an accident report since the FCC’s recent regulatory action and issued recommendations to both the US DOT and the FCC. 

To set the scene, it was January 5, 2020, 3:30am—so it’s dark outside, on a mountainous curve with a 55mph advisory speed and slight precipitation. A motorcoach entered the curve at 77mph, and the excessive steering input from the motorcoach driver caused the motorcoach to overturn and come to rest perpendicular to the lanes of traffic. The initial rest position blocked both lanes and shoulders. 

Subsequent Crashes

After the motorcoach came to rest, three tractor trucks and a passenger vehicle struck the overturned motorcoach resulting in 5 fatalities and 50 injuries. 

C​ollision Avoidance Systems

The picture of the overturned motorcoach on the slide was taken from the FedEx truck’s forward-facing camera. The FedEx driver described the overturned motorcoach as a black wall—making it very difficult to see.

All three tractor trucks were equipped with a collision avoidance system including Automatic Emergency Braking. 

The NTSB found that the ci​rcumstances of the impact for each of the three trucks were likely outside the capabilities of the collision avoidance system on the vehicle. 

L​​imitations of Onboard Sensors

Many of the current limitations to onboard line-of-sight sensors were present in this crash such as seeing around a curve, inclement weather, and an unexpected orientation of the overturned motorcoach. 

Therefore, the NTSB found that connected vehicle technology, if it had been installed on the vehicles involved in the crash, could have provided information to the drivers of the tractor trucks and passenger vehicle so that the drivers could be alerted to the overturned motorcoach. 

Harmful Interference

At the NTSB, we strongly support V2X technology because of its promise to save lives. Crashes can happen very quickly, so to prevent crashes, the communication between vehicles must be accurate and reliable. There’s little room for error. When harmful interference is introduced to that communication, the accuracy and reliability is impaired. 

In the Mt. Pleasant report, we found that recent regulatory action by the FCC allows for the potential of harmful interference from unlicensed devices and threatens the deployment of V2X technology, therefore we recommend that the FCC implement appropriate safeguards to protect V2X communication from that harmful interference. 

Regulatory Uncertainty

Unequivocally, regulatory uncertainty has hindered the deployment of V2X technology. For years, the industry was developing the technology based on the assumption that it would be deployed in a protected 75mhz band. Then, the FCC shrunk the spectrum by 60% and introduced the potential for harmful interference. This created significant regulatory uncertainty and had a severe chilling effect on the industry. 

At the NTSB, we recognize industry’s scars from the recent regulatory upheaval, but we cannot let those scars prevent us from realizing the benefits of V2X. The only path that remains is forward. 

To solve the remaining regulatory uncertainty and achieve widespread deployment, it will require buy in from automakers and infrastructure owner operators and coordination among various federal agencies such as the DOT and FCC. The NTSB believes the DOT, at the Secretary level, is in the best position to coordinate and these efforts. Therefore, in the Mt. Pleasant report, the NTSB issued a recommendation to the Department of Transportation to implement a plan for nationwide connected vehicle deployment and to solve the outstanding problems such as interference from out of band emissions, insufficiency of spectrum for advanced V2X applications, and division among communication protocols. 

Path Forward

We must overcome previous challenges to achieve the immense safety promise of V2X. The only path that remains is forward. To move forward, first the DOT and FCC must provide industry with regulatory certainty that allows for the widespread deployment of V2X technology. Regulatory certainty will immediately incentivize stakeholders to increase V2X investment and deployment. I have spoken to automakers and infrastructure owner operators who remain committed to V2X technology but instead are on the sidelines due to the volatile regulatory environment. I am encouraged by this V2X summit as an initial step and encourage the DOT and FCC to continue to work alongside industry to provide a supportive regulatory framework. 

Industry must also act. We have seen many pilot deployments on the local level demonstrating the potential safety promise of V2X, but that safety promise cannot be achieved without widespread deployment from automakers. The full safety promise of V2X is only realized when we reach a critical mass of vehicles on our roadways.

Last year, nearly 43,000 people lost their lives on our roadways. V2X is one of the most promising safety technologies available and it presents an opportunity to significantly reduce the number of fatal crashes. Your work during this summit and continued support of V2X technology will save lives.

V2X Resource Page

To learn more about the NTSB’s V2X investigations and recommendations​, and to access the four-part video series I hosted on preserving the future of connected vehicle technology, please visit