Photos by JUSTIN COOK The Roanoke Times

Crash investigator trainees work a staged crash Thursday in a parking lot at Virginia Tech. The test was part of a training course for law enforcement officers from the New River Valley and other areas of the state.

All the officers on the crash team, shown taking part in a training exercise, completed a two-week course in which they learned the basics of crash investigation, including how to determine whether someone's headlights or turn signal were on during a crash, and a weeklong course that focused on the diagrams and extensive math involved in crash reconstruction.

BLACKSBURG -- The Oldsmobile Alero's engine revved and its tires squealed just before it slammed into the driver's side of the parked Chevrolet Chevette with such force that the Chevette's roof popped upward and the tires bent out.

Had anyone been inside the Chevette, the Thursday morning crash could have been fatal. Had the Alero's driver not been wearing a seat belt, he could have been seriously hurt.

But this carefully planned crash in a parking lot at Virginia Tech was conducted as part of a training course for law enforcement officers from the New River Valley and other areas of the state.

And the driver was Gary Lewis of Accident Analysis & Reconstruction, who is also a corporal with the Montgomery County (Md.) Police Department. Lewis said he has served as the driver for about 70 such crashes.

"It's important because we want to make things as realistic as possible," he said.

The officers say being able to witness crashes will help them with their investigations.

"It's a lot different than just measuring chalk marks on the pavement," said Sgt. Mark Hollandsworth with the Montgomery County Sheriff's Office.

Hollandsworth and several other officers who are taking part in the two-week training course, which ends today, are part of the New River Valley Regional Crash Investigation Team. It includes officers from the sheriff's office and the Christiansburg, Blacksburg, Virginia Tech and Radford police departments.

"We pool resources and pool money and share equipment," said Investigator Eric Snow with the Montgomery County Sheriff's Office.

Most of the team's funding for training and equipment comes from the Virginia Department of Motor Vehicles, he said.

When someone is seriously injured in a crash, the team reconstructs it through diagrams to determine the vehicles' speeds and other information. Crash investigations can take several weeks.

All the officers on the crash team have already completed a two-week course in which they learned the basics of crash investigation, including how to determine whether someone's headlights or turn signal were on during a crash, and a weeklong course that focused on the diagrams and extensive math involved in crash reconstruction.

"This class builds on the first two levels of training," Hollandsworth said.

For most of the two-week session, which is conducted by Accident Analysis, a Maryland-based company, the officers were in a classroom. They learned how to apply various mathematical formulas as part of their investigations and how to put together cases for prosecution.

Then, on Thursday, officers from the New River Valley team, Virginia State Police, Roanoke, Roanoke County, Franklin County, Newport News, Virginia Beach and Chesapeake gathered in the campus parking lot known as "the cage" to apply what they had learned.

They started the day by causing donated junkyard cars to skid on the parking lot's asphalt so they could determine the coefficient of friction, "to know how much grab the pavement has," Hollandsworth said.

It's something they do when conducting most crash investigations, he said, because it helps them to learn about the crash from any skid marks.

Part of the Accident Analysis class involved learning how to estimate vehicle speed and other data in the absence of skid marks.

"The information being given to these officers is state-of-the-art and adds a whole new dimension to their investigation skills," said Lenny Simpson, a collision-reconstruction consultant with Accident Analysis.

Officers taking part Thursday were divided into three teams, each of which investigated a crash. With a Total Station, a combination electronic transit and distance measuring device used by surveyors, they drew scale diagrams of each crash.

For the Alero vs. Chevette crash, they also downloaded the information stored in the Alero's airbag control module, such as the engine rpm, vehicle speed, throttle percentage and brake application.

But Simpson said they couldn't see that information to compare it with their own findings until this morning.

"They have to do the work first," he said.