All too often, bad weather forces planes to make detours of hundreds of kilometers, sometimes creating delays that ripple nationwide. Help is on the way: this summer a new weather prediction system will come on line, allowing more precise air traffic routing, and even showing aircraft safe routes through storms-with a $45 million-per-year projected savings for airlines and travelers.

Designed at MIT’s Lincoln Laboratory, the weather prediction system starts with an existing radar network, which covers large regions and updates information every six minutes. Air traffic controllers currently rely on this network to monitor weather in the areas between airports. The new system will incorporate both it and the two additional kinds of radar network that are currently used only to cover air space near airports, but which are more precise and send updates every four seconds. “Nobody had tried to stitch them together before” to cover air space between airports, says Jim Evans, an electrical engineer at Lincoln Labs and lead designer of the system. The technology adds information from satellites, which detect evolving storm clouds that aren’t visible on radar, and provides a three-dimensional analysis showing where planes can fly above trouble spots.

The Federal Aviation Administration plans to implement the weather prediction system in the congested Boston-Chicago corridor this summer, where it will provide detailed two-hour storm front predictions that show “holes” in bad weather through which planes can safely fly. “Basically, it will improve efficiency,” says Dan Strawbridge, an FAA team leader for weather programs, who is helping implement the Lincoln Lab project. Weather accounts for about 70 percent of aviation delays and costs airlines $3.5 billion annually, he says. “We can do away with some of those delays with this technology,” says Strawbridge.

Indeed, Lincoln Lab said last year that a more localized version of the technology, which it installed in the New York City area, saves travelers and airlines more than $150 million annually (see “The Digital Sky,” TR March 2001). The new regional system will only work in heavily trafficked corridors that have a high concentration of airports and their radar. But as any traveler to Boston’s Logan or Chicago’s O’Hare Airports can testify, that’s where the delays are happening-at least for now.