AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
American Airlines Flight 1420 Case Study
School of Aeronautics, Liberty University
AVIA 340: Aviation Weather
March 4, 2024
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
Introduction
The McDonnell Douglas MD-82, which was operating as American Airlines Flight 1420 and
registered as N215AA, crashed by overrunning the end of the runway while landing at Little
Rock National Airport on June 1, 1999. The accident involved two crew members, four flight
attendants, and 139 passengers aboard. In this case study, the investigation of the incident is done
by exploring the synopsis, causation, and overall analysis of the events that led to the accident.
The paper further discusses the decision criteria, implications, recommendations, and personal
narrative to understand how to prevent similar accidents in the future. The analysis further
studies the relevance of weather and its implications in the aviation industry. Furthermore, the
essential components of the case study are derived from the National Transportation Safety
Board accident investigation report.
Synopsis of the Incident
The flight departed from Dallas Fort Worth International Airport, Texas, around 2240. It
reached Little Rock at 2350. After leaving the runway, the aircraft collided with the structure
supporting the runway 22L approach lighting system, went through a chain link security fence,
crossed a rock barrier to reach a flood plain, which was about 15 feet below the runway
elevation, and struck multiple tubes that extended outward from the left edge of the instrument
landing system localizer array, which was 411 feet beyond the runway's end. As a result, ten
passengers and the captain were killed while the flight attendants, the first officer, and 105
passengers were seriously injured (“Runway Overrun During Landing American Airlines Flight
1420 MCDONNELL DOUGLAS MD-82, N215AA Little Rock, Arkansas”, 2001). Another 24
passengers were left uninjured. The plane was destroyed because of the impact and fire. The
report from the National Transportation Safety Board states that the significant cause that led to
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
the accident was the failure of the flight crew to stop their approach when they were informed
about the severity of the weather conditions during the day of the incident. There were severe
thunderstorms that could most definitely affect the flight operations at the airport area, which the
flight crew ignored (Wald, 1999). Further, the National Transportation Safety Board inferred the
poor decision-making of the crew, especially in not ensuring the extension of spoilers after
touchdown, their impaired performance that was derived from the stress and the continuation of
landing even with the exceeded maximum crosswind component, etc. The cause of the accident
prominently revolves around the operation of the flight in adverse weather and weather
information dissemination. Further, the importance of emergency response and the frangibility of
the airport structure specific to this incident helps understand the safety recommendations
required to mitigate similar cases.
Causation
The probable causes for the accident, as stated by the National Transportation Safety Board,
were the following. Firstly, the crew should have stopped the approach with the knowledge of
severe thunderstorms in the area surrounding the airport and undermined the known risk of the
weather towards the flight operation. Following this, the crew also did not ensure that the
spoilers were extended after the touchdown (“Runway Overrun During Landing American
Airlines Flight 1420 MCDONNELL DOUGLAS MD-82, N215AA Little Rock, Arkansas”,
2001). Next, the flight crew's performance was impaired because of the fatigue and situational
stress from the need to land under challenging circumstances—the continued approach to landing
when the maximum crosswind component of the company was exceeded. Lastly, the use of
reverse thrust was greater than the 1.3 engine pressure ratio after landing.
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
When the flight departed, the crew received the American Airlines weather advisory about the
area of thunderstorms along the planned route for this flight. This advisory was a part of the trip
paperwork. Also, it included another two weather advisories from the National Weather Service
along the area of severe thunderstorms that did mention the route the plane was taking. After
departing, the flight crew was given an ACARS message from the flight dispatcher about the
weather at the landing site and how it might affect the flight's arrival. The message suggests that
the flight crew should accelerate the arrival process so they can beat the thunderstorms, and the
crew admits to this message (“Runway Overrun During Landing American Airlines Flight 1420
MCDONNELL DOUGLAS MD-82, N215AA Little Rock, Arkansas”, 2001). The information
about evaluating conditions that show the development of severe storms from the forecasting in
the landing area was valid. This indication further suggested the unstable atmosphere driven by
the severe thunderstorms.
The American Flight Manual, which specifically addresses weather protocols, has instructions
on thunderstorm avoidance. According to the manual, it is a given that the flight should not enter
or depart when the areas are blanketed by thunderstorms, except when the routes are
thunderstorm-free. The approach and the decision-making guidance while landing state that the
action of landing or taking off is not permissible when the airport area shows signs of
thunderstorms or has them. The only exception is when the runway and the flight path are clear
of hazards. The report from the NTSB also states that the flight crew was informed about the
weather by the NWS Convective SIGMET 15 C and from the ATIS, all indicating the occurrence
of thunderstorms along with lightning located northwest of the airport. The training programs
stress the importance of avoiding thunderstorms during routine operations. However, research
shows that pilots sometimes penetrate thunderstorms like this but are always followed by
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
disastrous results. Hence, in this case, the flight crew did not consider the significance of the
effects of thunderstorms while landing was the leading cause of the incident.
Another cause comes from the spoiler deployment as it is essential for an optimal landing
performance. The flight spoilers are extended and retracted automatically through a hydraulic
actuator. The human factor in operating the spoilers is to ensure the efficiency of the auto spoiler
system in engaging the spoiler system. However, after the accident, it was seen by the
investigators that the ground and the flight spoilers were retracted, and they did not deploy
during the touchdown. The pilot plays a crucial role in this action, and the reason they did not
automatically deploy was that the pilot did not arm the handle before landing. The crew did not
verify the automatic deployment of the spoilers after landing, while the captain failed to
manually extend it (“Runway Overrun During Landing American Airlines Flight 1420
MCDONNELL DOUGLAS MD-82, N215AA Little Rock, Arkansas”, 2001). The investigation
of the incident further suggests that no amount of warning regarding the weather would have
changed the outcome because of the impaired decision-making conducted by the flight's crew.
The errors in the operation and the situational pressure that resulted in poor decision-making
skills are listed as important causes of the accident.
Aviation considers crosswinds a significant factor in an efficient landing. In the report, The
influence of crosswind hazards in the accident was determined by NASA scientists. Their
examination confirmed the “bow echo” squall line systems present in the airport when the plane
was landing and further proved the production of hazardous crosswinds. The threat from the
crosswind during this situation includes the lack of control in operations and collision with
various obstacles, all leading to the damage of the aircraft. But more importantly, there is an
unstable directional control on the runway. The 20-25 knot crosswind component found during
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the incident exceeded the 10-knot limitation that is considered normal by the flight manual for an
ideal landing. The crew members were aware of the crosswind, however still failed at
implementing directional control on the runway, even when the component exceeded its
limitation point. Reversal thrust is the slowing down of the aircraft when landing, and the thrust
is projected in the opposite direction. During the accident, the pilot applied excessive reversal
thrust considering the landing situation that had converted to the status of emergency. However,
according to the manual, when the airplane is drifting across the runway while reversing, the
pilots should regain directional control by coming out of the reverse thrust (“Runway Overrun
During Landing American Airlines Flight 1420 MCDONNELL DOUGLAS MD-82, N215AA
Little Rock, Arkansas”, 2001). The safety board concluded that the maximum reverse thrust for
the landing in wet runways, like this case should be 1.3 EPR. Anything greater than that reduces
the effectiveness of the rudder and vertical stabilizer, resulting in the aircraft crash.
Decision Criteria
The decision criteria to infer the causes and continue the analysis procedure in the case study
use popular opinions and the significant elements that contributed to the accident. The weather
conditions, situational stress exhibited by the flight crew, exceeding the maximum crosswind
component, a greater reverse thrust, and most importantly, the failure of deploying the spoilers
during the touchdown. These components serve as the qualified variables to evaluate and infer
the incident. However, there is a need to highlight the role of weather as a primary point of
concern in this event and how its study is relevant to the aviation industry.
Since the advancement of commercial aircraft, flying into thunderstorm conditions has been a
major source of concern. This specific study gets a lot of attention because of the growing
significance of air travel and the accelerating speed of airplanes. Research shows that to
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
accurately come up with a plan for flying over the top of an ordinary thunderstorm, the
assessment of the storm's vertical extent should be conducted, which is then followed by the
analysis of the flight path (Sawyer & Reichelderfer, 1949). During the time of the incident, the
limited use of radar in meteorological monitoring may have influenced the poor estimation of the
maximum vertical extent of thunderstorms. Also, the studies suggest that the storm peaks can be
invisible from the ground because of the stratified clouds that are either at the cloud's base or at a
higher altitude. Weather studies show that the storms that all thunderstorms share a fundamental
structure and are composed of the same meteorological elements. The thunderstorm is composed
of numerous "thunderstorm cells," and every one of these cells develops autonomously from its
neighboring cells (Sawyer & Reichelderfer, 1949). This shows that the process of building up the
storms is a cycle that takes place for a specific duration of time. The aftermath of the
thunderstorms includes rain, snow, ice, and the occurrence of lightning strikes in the area
affected. When flying through a thunderstorm, the intensity and frequency of the turbulent
motions are commonly thought to determine the storm's severity. Further, there can be rapid
variations in surface pressure, where the pressure rises quickly, remains high for a few minutes,
and then returns to its pre-thunderstorm value. The characteristics of a thunderstorm show the
difficulties for a flight operator to safely navigate the journey of the plane (Onwuadiochi et al.,
2023). Because of the geographical area that covers the airports, the collision of flight operations
with thunderstorms is more common, and hence the research on the subject becomes even more
essential.
The series of events that start from the weather conditions to the inappropriate landing of the
aircraft all contribute to the outcome. Hence, the many variables that have played their role are
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
taken into consideration and explored to analyze the case and arrive at the findings and the
probable recommendations.
Analysis
The flight crew received plenty of information regarding the weather conditions. For
example, the NWS weather advisories and company SIGMEC reports explicitly stated the
condition of thunderstorms approaching the airport area. Along with this, the flight dispatcher's
message about the thunderstorms at both the left and right of the planned route and the additional
suggestion of expediting the arrival shows that the warning signs were clearly ignored by the
flight crew, and this directly influenced the events that resulted in the crash of the airline. The
crew members had access to the weather information from the radar and the view that could be
seen outside the cockpit. The discussion of expediting the arrival was done by the crew after
being notified about the conditions of the landing. When one specific operational need, which
was the company's maximum crosswind component for carrying out the landing, was exceeded,
the flight crew should have started a go-around during the final approach. Although this
approach is not necessary when there is an incapacity to maintain a normal rate of descent or
successfully achieve the final landing flap configuration, it is still an ideal option otherwise
(“Runway Overrun During Landing American Airlines Flight 1420 MCDONNELL DOUGLAS
MD-82, N215AA Little Rock”, Arkansas 2001). Mainly because, as seen in this case, the
likelihood of finishing the approach successfully was almost null, considering the poor planning
of the flight crew and the quickly worsening weather circumstances. If the spoilers had been
deployed appropriately, the manual braking profile used, and a reverse thrust of 1.3 EPR
preserved, the accident would have been prevented by stopping the plane on the runway without
crashing it. However, the most essential role here would be of the spoilers, and with the absence
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
of this action, it would be impossible to change the outcome of the incident. This is the reason
why the incapability of the flight crew to conduct the above-mentioned steps has directly
impacted the accident.
The crew members primarily failed to do necessary callouts during the accident flight and did
not adequately assess the available meteorological cues or take into account their significance.
For instance, they were informed about the likelihood of a thunderstorm reaching the airport.
However, it is crucial to note here that they were not given detailed operational decision-making
guidelines on how to penetrate convective activity but were only supplied with broad, advisory
information on how to overcome extreme weather conditions. The flight crew was under
pressure to speed up the landing due to the possibility of weather posing a hazard to flight safety.
Studies have indicated that when people are under stress, their ability to make decisions can be
compromised as a result of their selective attention to a limited number of variables. Hence, any
judgment made, even from the expert point of view, can be considered as of lower quality. Stress
makes it difficult to rely on different possibilities, thus, forcing the crew to go with the original
plan that was a bad one in this case. Also, the determination to accelerate the landing in the
presence of extreme weather conditions resulted in them unnoticing the other essential
responsibilities required for an efficient landing. Studies show that fatigue can make it difficult
for pilots to weigh their options when they become fixated on an outcome they want. Further,
they may forget to complete essential tasks because of situational stress. Through the analysis it
is seen that the first officer neglected to check the auto spoilers, the captain forgot to call for
flaps 40, and the flight crew did not consider the possibility of deviating from the landing. Along
with other significant factors that contributed to the outcome, fatigue also played an important
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
role in deteriorating the performance of the flight crew and failing them to conduct routine tasks
during the final approach effectively.
Implications
The implications drawn from the case analysis are that no single entity is solely responsible
for the incident. However, a series of decisions and consequences all lead to an outcome that
could be prevented. As per established corporate procedures and Federal rules, the airplane was
duly certified, equipped, and maintained. There was no proof of any prior structural, mechanical,
or engine issues. The flight crew members predicted that they may arrive at the airport before the
storms before they reach the landing area. The confidence mainly came from the first officer
keeping visual contact with the runway. The flight crew should have decided against the
approach to runway 4R when they received the second wind shear indication, especially when
they had exceeded the maximum crosswind component needed. At this moment, the possibility
of a safe landing started to decrease. Their only option was to land the plane safely through an
alternate course of action. However, even that did not work because of the inefficiency of crew
members to respond in an emergency in quickly deteriorating weather conditions. Another
important conclusion drawn is the essentiality of verifying the deployment of the spoilers during
the landing operations (“Runway Overrun During Landing American Airlines Flight 1420
MCDONNELL DOUGLAS MD-82, N215AA Little Rock, Arkansas,” 2001). The failure to do
this resulted in the difficulty in halting the aircraft within the runway length and having control
over the plane on the runway. These various findings show the many policies, research, and
practices required to be conducted by the aviation industry to further prevent similar cases. For
example, policies that emphasize the role of emergency responders arriving at the accident scene
while utilizing crash detection and the use of GPS should be developed by corporations
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
(Onwuadiochi et al., 2023). This practice could result in a positive outcome where more lives are
saved. Research around developing advanced technological assets that enable the conversion of
non-frangible structures into frangible ones could enhance airport infrastructure safety. Training
programs that would help pilots distinguish between an unstabilized approach and a stabilized
approach is also another opportunity raised from this case analysis. There should be extensive
research and training made on the stabilized approach criteria for air carriers because of their
significance in flight operations.
Recommendations
The case of American Airlines Flight 1420, shows the various protocols that should be
essentially followed by the flight crew. Some of the recommendations are discussed here. The
automatically equipped aircraft must have two crew members to confirm that the spoilers are
armed before landing. This procedure should be integrated into the training manuals, checklists,
and flight manuals. They additionally need to call out when the spoilers have deployed and if
they do not deploy automatically or manually during landing. The protocols should specify
precisely which pilot is in charge of issuing these alerts while also ensuring the responsibility of
another pilot in deploying it automatically or manually when the former does not work. The
flight standards information bulletin should be developed that states explicitly about the
emergency conditions where directional control must be given up in favor of a shorter stopping
distance (“Runway Overrun During Landing American Airlines Flight 1420 MCDONNELL
DOUGLAS MD-82, N215AA Little Rock, Arkansas,” 2001). The analysis shows that this
specific type of airplane must utilize a maximum reverse thrust power of 1.3 engine pressure
ratio on wet or slippery runways. The principal operations inspectors should ensure that the
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
operators' flight manuals and training materials discuss the rudder effectiveness reduction that
happens when reverse thrust power is applied beyond the 1.3 engine pressure ratio.
The operators should use functional automatic brakes for landings in wet, slick conditions, or
strong crosswinds like this case. To address feasible operational strategies and guidance for
lowering thunderstorm penetrations, establish a working group that includes government and
industry representatives (Anaman et al., 2017). These strategies and guidance materials should
be incorporated into air carrier flight manuals and training programs. The study of airspace
systems should be emphasized, particularly the ground- and cockpit-based solutions. The
immediate goal should be to develop precise and effective standards for identifying signs of
severe meteorological activity. Following this, suggestions for enhancing flight crew decision-
making should be developed. Designing a near-real-time color weather radar monitor at all air
traffic control stations with accurate precipitation levels should be done. During a severe weather
prediction, the flight systems should work along with the National Weather Service to ensure
that there are plenty of staff to efficiently respond during an emergency. It is essential to direct
the controllers to watch the actions taken by Aircraft Rescue and firefighting crews to guarantee
their responses correspond with known location data (“Runway Overrun During Landing
American Airlines Flight 1420 MCDONNELL DOUGLAS MD-82, N215AA Little Rock,
Arkansas,” 2001). There should be scientifically supported research done to design an
appropriate amount of hours of work for the flight crew members to avoid stress and work
pressure that would directly influence their decision-making capabilities. The airlines should
necessarily implement operating procedures that are designed specifically by the aircraft
manufacturer and are also seen in their flight handbook. For any alternative adaptation regardless
of the situation, the operators should be able to explain why their modifications achieve a similar
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
level of safety (Onwuadiochi et al., 2023). This case further proves the inaccurate and random
observations done by the lockout feature of the Automated Surface Observing System. Hence,
limited use in understanding the weather by the flight crew should be mandatorily implemented.
Personal Narrative
Research shows that the flight engine and all the other equipment required for efficient flying
had no problem before the plane took off. The warnings regarding the thunderstorms
approaching the airport were also given to the flight crew. The outcome would have been
different if the responsible agencies had made decisions and planned their course of action with
other alternate strategies before flying the plane. Hence, more than the weather being the biggest
constraint here, the performance exhibited by the flight crew should be considered the turning
point leading to the events of the crash. The crew's performance in their decision-making shows
the lack of professionalism and awareness of the importance of weather conditions like
thunderstorms in interrupting the landing approach. This case is also an example of how
situational stress and work fatigue influence the behavior of the flight crew, which can
sometimes cause the biggest damage to all the stakeholders involved. Through the case study, I
could infer the concerns that should be raised by various issues and how they serve as
recommendations for the aviation industry for enhanced research and practice.
Conclusion
This case study examines the aircraft accident of American Airlines Flight 1420, which took
place in 1990. Although the causation of the incident is discussed in detail, the specific relevance
of weather and its association with the aviation industry is taken into special consideration. The
study's findings allow crucial opportunities for developing policies, research, and practice.
AMERICAN AIRLINES FLIGHT 1420 CASE STUDY
References
(2001). (rep.). Runway Overrun During Landing American Airlines Flight 1420 MCDONNELL
DOUGLAS MD-82, N215AA Little Rock, Arkansas. Retrieved from
https://www.ntsb.gov/investigations/AccidentReports/Reports/AAR0102.pdf.
Anaman, K. A., Quaye, R., & Owusu-Brown, B. (2017). Benefits of aviation weather services: A
Review of International Literature. Research in World Economy, 8(1), 45.
https://doi.org/10.5430/rwe.v8n1p45
Onwuadiochi, I. C., Egede, O. S., & Udeogu, A. C. (2023). Assessment of the impacts of
thunderstorms on flight operations at Murtala Mohammed International Airport, Ikeja,
Lagos State, Nigeria. Journal of Geographical Research, 6(1), 17–27.
https://doi.org/10.30564/jgr.v6i1.5057
Sawyer, C., & Reichelderfer, F. W. (1949). (rep.). A Report on Thunderstorm Conditions
Affecting Flight Operations.
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Wald, M. L. (1999, June 9). 3 safety features are absent at the Airport in Little Rock. The New
York Times. https://www.nytimes.com/1999/06/09/us/3-safety-features-absent-at-airport-
in-little-rock.html
