Suddenly, as the bus attempts to turn south onto another highway, a car slams into its left rear side, pinning the car's 16-year-old driver and his two passengers in the auto and injuring over 40 students on the bus. The scattered wreckage is concealed in fog. The injured wait helplessly for aid to arrive.
Trooper Tom Taylor, working another accident a short way down the highway, hears a noise but doesn't associate it with an accident. In fact, the fog is so dense, he doesn't even know what's happened until he receives a dispatcher's call. Even then, he can't see the wreckage until he is 20 yards away from it.
Although most of the children on board the bus are only bruised, the driver of the car and his two passengers are seriously injured and in need of urgent medical attention. But the foggy conditions prohibit an ambulance from reaching the scene quickly -- it's too dangerous.
A medflight helicopter is dispatched to the location, but it can't find the wreck. "The fog was so thick the medflight couldn't see anything on the ground," said Oklahoma State Trooper George Randolph, who arrived on the scene later. After several minutes of searching, the helicopter was just about to turn back, leaving the injured passengers stranded. "But Trooper Taylor -- thinking quickly -- remembered some recent training he received and a small device added to the equipment in his patrol unit -- a handheld GPS unit," said Randolph.
The GPS unit, called a GeoExplorer and made by Trimble Navigation Ltd., works by tapping into radio waves beamed from a network of 24 satellites that orbit the Earth more than 11,000 miles in space. These satellites broadcast navigation signals to users who can, through latitude, longitude and altitude, determine their position anywhere in the world.
"Trooper Taylor asked if the helicopter was equipped with a GPS and if the pilot could navigate using the latitude and longitude coordinates," said Deral Paulk, president of Topographic Land Surveyors of Oklahoma, the company that sold the GPS receivers to the Oklahoma Department of Transportation. "The helicopter did, and the trooper quickly moved to an open field next to the highway. After Trooper Taylor was patched through to the pilot, he relayed the coordinates of his position to the medflight helicopter."
Using the coordinates, the helicopter pilots were able to hover above the accident scene, and then slowly descend toward it. "As they got close to the ground," said Randolph, "the helicopter itself actually pushed the fog away so they could see and they landed and completed the rescue."
MAPPING ACCIDENTS
The Oklahoma Department of Transportation (ODOT) purchased the GeoExplorer units as part of a project to map the longitude and latitude coordinates of accident locations. Quick thinking by Taylor turned it into a rescue device.
"What they get," said Randolph. "is GPS to actually locate points of impact -- traffic accidents -- so they can get it onto a map and do all the analysis you can do with GIS." The GPS and GIS will help replace an obsolete grid-map system.
According to Randolph, other GPS-related data associated with traffic accidents will be used by other programs within the state, but the main reason the troopers received the GPS units from ODOT is so "accidents can be tracked a little closer to where they are actually happening. With that information, ODOT can do engineering studies and find out any problem areas that we have," he said. "The product will also store data for future use in the state's GIS."
NEW USES
Although this may have been the first time a GPS unit was used to guide a helicopter to a rescue, Randolph said a number of other uses have sprung
up since the department started using the tool.
"Our highway patrol tag teams use these also, and we've used them quite extensively on manhunts and stuff like that to give locations and improve navigation."
The Oklahoma Bureau of Narcotics has also been using GPS in an operation they run every year to spot marijuana fields. "They punch in locations on their GPS and then later they punch the same coordinates in on the ground and drive to the location," said Randolph. "Some of these areas in Oklahoma are so wooded you really can't see or know where you are at in the air."
And if another car accident should occur on a fog-covered Oklahoma highway, state troopers have another useful technology tool to help speed rescue attempts and save lives.
