Interstate 81 is a beautiful highway, running along Virginia's western edge in the shadow of the Shenandoah, full of picturesque curves and hills, offering stunning views of the mountains in the distance. Yet I-81 scares Franks Parsons to death. Yes, the interstate is quicker, but if he has, say, a doctor's appointment down the road, the 81-year-old retiree will take two-lane Route 11, thank you very much. No tractor-trailers filling his rear view mirror at 65 mph. No big rigs screaming by, their wheels almost at eye level, making his Volkswagen shudder. 'There's nothing more frightening than to see one of those things barreling up behind me,' he said. 'It's unnerving.' Trucks own I-81. They make up one of every four vehicles on the highway, and in some stretches, there is nearly one truck for every passenger car, according to the Virginia Department of Transportation, the highest ratio on any of Virginia's major highways and well above what I-81 was designed for. And when the trucks -- which can weigh up to 80,000 pounds -- are involved in crashes, the result is often spectacular -- and deadly. In Virginia, Interstate 95 suffers more crashes; between 2003 and 2007, it had more than twice as many wrecks as its country cousin, I-81. But a Washington Post analysis of state data shows that the fatality rate for crashes on I-81 was nearly double that of I-95. 'To be blunt: If you're driving a car and you have a truck in front and a truck behind and a truck passing you, it's not difficult to determine who the jelly in the sandwich is if things go bad,' said Lon Anderson, spokesman for AAA Mid-Atlantic. 'It's very frightening.' Last week was particularly bad. On a 15-mile stretch near the intersection with Interstate 66, there were four crashes in less than 10 hours between Thursday evening and Friday morning. The crashes involved nine tractor-trailers and two passenger vehicles and left several people injured. The first incident came at 7:20 p.m., when a tractor-trailer ran off the road and overturned in the median strip, spilling its load of watermelons. Police had to divert traffic off the highway, creating a jam that hours later was backed up for miles. Traffic was barely moving after 10 p.m., when Stone Taylor Weeks and William Holt Weeks came along in their 2007 Honda Civic, which weighed 2,600 pounds. The brothers -- the sons of National Public Radio journalist Linton Weeks, a former Washington Post reporter and editor, and Jan Weeks, a painter -- were on their way to their parents' home in Rockville, Md., from Houston. Their Honda was stuck in the traffic when a tractor-trailer rammed them from behind, forcing their car underneath the truck in front of them. A side gas tank on one of the trucks ruptured and 'a fire spread rapidly through the vehicles, burning the passenger vehicle beyond recognition,' according to a police news release. Both brothers were killed. The crash followed a similarly harrowing one in April in which three people died after three tractor-trailers and a passenger vehicle collided, setting off a fire. The highway was closed for about 16 hours. There are so many crashes, 'we don't even try to cover all the interstate wrecks,' said Darryl Woodson, editor of the Lexington News-Gazette. 'For every one we hear about and publish, there's got to be 15 that we don't.' The highway, which stretches from central Tennessee to the Canadian border, has long been popular among truckers as a north-south alternative to I-95 that lets big rigs avoid tolls and skirt the massive tieups around big cities such as Richmond, Washington and Baltimore. But since the North American Free Trade agreement went into effect in 1994, the highway has become even more densely populated with trucks ferrying goods from the border to U.S. marketplaces. It's not just tractor-trailers that fill the road. It's popular with tourists exploring the Shenandoah Valley. And with Virginia Tech and James Madison University located along the corridor, I-81 also carries one-third of the state's college students. Faced with public outcry about the death toll, the fear many motorists experience driving amid so many trucks, and the loss of the highway's once-bucolic character, Virginia transportation officials over the last decade considered building a parallel highway for trucks only. But the idea was shot down after officials determined it would create sufficient space for trucks, but wouldn't ease congestion for cars. More recently, officials looked at widening the highway from two lanes in each direction to four. But with the state in a financial crisis, and with tolls considered politically unfeasible, that is not going to happen anytime soon. The result has been incremental fixes here and there -- the state is adding truck climbing lanes at two spots near Blacksburg and Lexington, and it has extended some on-ramps to create more room to merge. But the large-scale improvements that officials say are needed are nowhere in sight. 'The fact is nothing is going to happen because there is no revenue,' said Fred Altizer Jr., I-81 program manager for Virginia's transportation department. -(Optional add end)- Environmental groups and preservationists have lobbied for more investment in rail, which they argue is a more cost-effective and environmentally friendly way to move freight and get trucks off the road. But that, too, has stalled because of insufficient funds.Meanwhile, traffic tripled in the Winchester and Roanoke regions in the last 20 years, from 20,000 to 60,000 vehicles a day. Truckers aren't always to blame. Often, it's car drivers who don't give trucks nearly enough room, and aren't aware that a tractor-trailer moving at 60 miles per hour can require the length of a football field to come to a complete stop. 'They'll cut in front of you all the time,' said James Sine, a trucker who stopped at the Flying J Travel Plaza in Winchester while making a run between Houston and Philadelphia. 'They pay no attention whatsoever. You blink and there's a car right in front of you.' Bill Oss, who's been driving I-81 since 1970, said he'd much rather have his rig surrounded by trucks, whose drivers are professionally trained, than cars, whose drivers buzz around seemingly oblivious to the fact that 'we can hit one of these people, and not even feel it except for a thump. 'I hate to say it,' he said. 'These cars, they don't have a chance.' 