Feb 24, 2012; 8:19 PM ET
A thunderhead (cumulonimbus cloud) like the one that flight 242 flew through.Photos.com
As part of AccuWeather.com's severe weather week, we take a look at three noteworthy airplane accidents where weather played a significant role in the disaster.
While not an exhaustive look at the impacts of weather on aviation, these three plane crashes arguably had some of the biggest impacts on aviation safety in adverse weather conditions.
The first installment in this three-part series is below.
The data for the following story was gathered from the official accident report issued by the National Transportation Safety Board.
Southern Airways Flight 242
The air was muggy and the temperature nearing the 80-degree mark on the afternoon of April 4, 1977, as Captain Bill McKenzie and First Officer Lyman Keele piloted Southern Airways Flight 242 into the sky over Huntsville, Ala., headed east toward Atlanta, Ga.
Over the next hour, weather conditions would rapidly deteriorate and put the lives of 81 passengers and four crew members in danger as the pilots struggled to keep their plane in the air.
A Muggy Spring Day
That early spring day dawned fairly mild across the southeastern United States. A morning temperature of near 60 degrees in Atlanta, Ga., made for a pleasant early morning. The mercury climbed into the 70s by midday; however, the ideal outdoor activity weather would have dire consequences in the afternoon.
A cold front slicing through the Southeast began to trigger thunderstorms across Tennessee and Alabama by early afternoon. Rapid upward motion and cold air aloft combined with ample surface warmth and moisture created an environment ripe for severe thunderstorms.
Before leaving Huntsville, McKenzie and Keele had been informed of tornado watches issued for northern Alabama and northern Georgia that afternoon. There was no other specific information passed along to the pilots regarding bad weather between Huntsville and Atlanta.
What they did not know was that a line of severe thunderstorms, with a history of producing hail and tornadoes, was directly in their flight path.
Minutes after takeoff, Flight 242 entered a heavy thunderstorm. Both pilots attempted to use their in-flight weather radar to find a region of clear air.
Despite seeing an area on their radar that looked calmer, it was actually the strongest area of the storm. The pilots didn't realize that the heavy rain caused the radar to inaccurately portray an area of hail as an area of light precipitation. This can be a common problem but flight crews are not necessarily properly trained to recognize it.
By inadvertently entering the most intense part of the thunderstorm, the pilots had sealed their fate.
A plane similar to the aircraft piloted by McKenzie and Keele.
Photo by Flickr user Dean Morley
Photo by Flickr user Dean Morley
A Fatal Mistake
Immediately, large hail began to pummel the DC-9 aircraft. Large amounts of rain and ice ingested into the engines caused them to surge. Soon after, they both quit working due to extreme damage.
As the plane descended, it broke out of the storm but now had no engine power. This type of emergency (permanent loss of thrust to both engines) had never occurred in the history of commercial, turbo-jet aircraft. The pilots were faced with an nearly impossible situation.
Despite a valiant effort by the crew to land the plane on a portion of road near New Hope, Ga., the plane's wing clipped a gas station during landing, bursting into flames. Of the 85 people onboard, 63 perished in addition to 9 on the ground; 23 survived.
Immediately, the investigation's focus turned toward the weather. Why had the pilots flown into a severe thunderstorm? Could the accident have been prevented? Did the flight crew have the information they needed to make proper decisions?
See more Severe Weather Week stories.
A Lack of Communication
In the end, the National Transportation Safety Board (NTSB) concluded that important weather information had never been disseminated to the pilots of flight 242. They never knew that the storm in their flight path was severe due to no ground-to-air communication. Instead, they trusted their in-flight radar and made a grave mistake.
The NTSB recommended several improvements to the integration of weather information in the aviation industry. The development of weather systems that allowed real-time display of important meteorological information was expedited. In 1977, Doppler radar was still relatively unreliable and untimely.
In addition, the NTSB suggested that significant meteorological events be transmitted more frequently so that pilots were more aware about the hazards of severe weather. Proper dissemination of thunderstorms watches and warnings was also analyzed and improved.
While many of these changes may seem trivial today, they were ground-breaking over 30 years ago. The knowledge of weather and its impact on aviation has drastically improved since flight 242 crashed in 1977. However, less than 10 years later, a sultry summer day in Dallas, Texas, would turn deadly and an invisible killer would be revealed.
Stay tuned for the second installment of this three-part series focusing on Delta Airlines Flight 191, to be published on Tuesday, Feb. 28.
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