16 years ago today, I was the Investigator-In-Charge of (IIC) of the accident involving American Airlines Flight 1420, an MD-82, N215AA, that had departed from Dallas/Ft. Worth (KDFW) to Little Rock, Arkansas (KLIT) on June 1, 1999. The crew was attempting to land on runway 4R in a thunderstorm and overran the runway, eventually colliding with the localizer antenna and the steel catwalk structure that held the approach light systen for runway 21. Of the 145 people aboard, the captain and ten passengers were killed in the crash.
The crew had departed DFW several hours late due to weather and were “racing” to depart the area before the convective activity intensified. As the crew approached KLIT, they could see the lightning and were made aware of continuous wind shifts and windshear alerts generated by a thundstorm by the KLIT tower controller. Due to a wind shift, the captain chose to land on runway 4R rather than 22L. As the aircraft approached Runway 4R, a severe thunderstorm moved overtop of the airport with strong gusting winds and windshear. The controller’s last report prior to the landing indicated the winds were 330 degrees at 28 knots with gusts to around 45 knots. The wind conditions exceeded the MD-82’s crosswind limit (10 knots) for landing in reduced visibility on a wet runway. Although the cvrew should have abandoned the approach, they continued the approach to Runway 4R.
It was apparent that both pilots (especially the co-pilot since he was on one of his initial operating experience (IOE) flights) became task-saturated which led to to decision errors and missed items on the checklist. The crew failed to arm the automatic ground spoiler system and they failed to arm the auto braking system. Both automatic deployment of the ground spoilers and automatic engagement of the brakes are essential to ensure the plane’s ability to stop within the confines of a wet runway, especially one that is being subjected to strong and gusting winds.
The Doppler Radar picture depicts the significant weather over the airport and the flight path of the airplane as the crew altered flight path to runway 4R. The red area is the most dangerous part of the storm.
The animation picture shows the airplane tocuhing down on the runway off centerline, just pripor to the loss of directional control. It was at this point that, immediately after landing that the First Officer stated, “We’re down. We’re sliding.” This was followed by the captain saying “Oh No!” Neither pilot observed that the spoilers did not deploy, so there was no attempt to activate them manually, thus the result was almost no wheel braking action because only about 15 percent of the airplane’s weight was supported by the main landing gear. Unfortunately directional control was lost when the Captain applied too much reverse thrust in contradiction to the limits stated in the flight manual. The application of too much reverse thrust disrupts the air flow over the rudder (because the engines are mounted on the aft fuselage) which is used for lateral directional control at high speeds. The combination of a loss of directional control and poor wheel brake action resulted in the aircraft overruning the paved surface of the runway, the grass over run area and becoming airborne momentarily, and eventually colliding with the approach light structure.
There were numerous Safety Recommendations issued after this accident including a re-iteration of a Safety Recommedation about unrestrained lap childrem.. This accident, as well as several other accidents and incidents prompted me and my business partner to invest the LAPKIDZ infant/toddler child retstraint system.