As thunderstorm season approaches in the Northern Hemisphere, it’s worth remembering how weather-radar technology has improved in the past three decades. Southern Airways Flight 242, a McDonnell Douglas DC-9, crashed in Pauling County outside Atlanta on April 4, 1977, after flying directly into a severe thunderstorm, calling attention to the then little understood issue of radar signal attenuation in areas of heavy precipitation.

Sixty-three people aboard the aircraft and nine people on the ground died in the crash, while 19 aboard the aircraft survived. Before takeoff from Huntsville, Ala., the two pilots were warned of embedded thunderstorms and possible tornadoes, but they were not told storms had already formed into a squall line. As the flight descended toward Atlanta, the crew used the onboard weather radar to pick their way through the line. At 14,000 feet near the Rome, Ga. VOR, the pilots were unaware the radar’s signal could not penetrate the precipitation and was actually sending them into the heaviest of the storms.

Investigators believe the lack of a solid radar return fooled the crew into believing weather just ahead was better. Within minutes of entering the heaviest rain, both engines ingested massive amounts of both water and ice and flamed out, and the windshield was destroyed by hail. Attempts to restart the engines were unsuccessful. Beneath a 500-foot ceiling with local visibility of less than a mile, the crew found a country road to use as an emergency landing strip. Shortly after touchdown, however, the DC-9 struck a gas station along the side of the road and exploded.