Systems that allow drivers to take their hands off the wheel will be the focus of NTSB hearing

The advanced systems that allow drivers to take their hands off the wheel while going down the road will be scrutinized again by federal investigators on Tuesday in connection with two fatal crashes involving Ford's Blue Cruise system.

The National Transportation Safety Board is expected to recommend ways to improve these partially automated driving systems as it wraps up its investigation into the 2024 crashes in Texas and Pennsylvania that killed three people when the Ford Mustang Mach-E cars slammed into vehicles that were stopped.

The NTSB has previously investigated a number of other crashes involving similar systems, including Tesla's autopilot system.

Ford and other automakers emphasize that these systems are not designed to replace the human drivers sitting behind the wheel, who have to be ready to take control at any time. The NTSB has said their investigation is examining the effectiveness of these systems and how well they monitor driver engagement.

But Missy Cummings, a professor of engineering and computing at George Mason University, said these crashes highlight some of the dangers of partially autonomous driving systems that allow people to disengage.

"Allowing people to take their hands off the wheel will also mean they will likely take their minds off the driving task,” Cummings said.

Ford’s Blue Cruise system does allow drivers to take their hands off the steering wheel while it handles steering, braking and acceleration on highways. The company says the system isn’t fully autonomous and it monitors drivers to make sure they pay attention to the road.

There are no fully autonomous vehicles for sale to the public in the U.S.

One of the crashes occurred in San Antonio, Texas, killing one person, while the other happened in Philadelphia in which two people died. The driver in the Philadelphia crash was later charged with DUI homicide. That criminal case is still pending with no trial date set.

The Texas crash occurred on Interstate 10 in San Antonio. The NTSB report says the Mach E struck the rear of a 1999 Honda CR-V that was stopped in the middle of three lanes around 9:50 p.m. The 56-year-old driver of the CR-V was killed.

Another driver who was able to avoid the CR-V told investigators that neither its tail lights nor hazards were working at the time.

The other crash involving a Mach E killed two people around 3:20 a.m. March 3 in the northbound lanes of Interstate 95 in Philadelphia. The Pennsylvania State Police said the Ford was in the left lane when it struck a stationary Hyundai Elantra that earlier had collided with a Toyota Prius.

During the crash, the driver of the Prius, who was outside of his vehicle, also was struck and thrown into the southbound lanes. A person from the Hyundai also was on the roadway and was hit. Both young men died.