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Enhancing Customer Satisfaction in the Airline Industry:
A Case Study of Delta Airlines
Xinhe Ma1,a,*
1College of Liberal Arts, Colorado State University, Colorado, 80523, USA
a. kenniema@colostate.edu
*corresponding author
Abstract: Customer satisfaction plays an increasingly important role as it drives customer
loyalty, fosters positive brand image, and provides a competitive advantage. Airlines that
prioritize customer satisfaction are better positioned to thrive in a highly competitive market,
attract and retain customers, and achieve long-term success. This paper focuses on enhancing
customer satisfaction in the airline industry, with a specific case study of Delta Airlines. The
study utilizes sentiment analysis techniques to analyze customer reviews from Skytrax and
conducts a comprehensive SWOT analysis. Based on the analysis, targeted suggestions are
provided to Delta, including leveraging technology to reduce the negative impact of delays,
establishing uniform service standards, broadening global networks and partnerships,
committing to sustainability and ESG initiatives, and ensuring quick responses to policy
changes. However, the study acknowledges limitations such as reliance on a single data
platform, the subjective nature of sentiment analysis, and the oversimplification inherent in
SWOT analysis.In all, this study helps Delta to improve its customer satisfaction and
contributes an research example to explore customer satisfaction in the airline industry.
Keywords: customer satisfaction, airline industry, Delta Airlines
1. Introduction
Driven by globalization, technological advancements, covid-19 pandemic and changing consumer
preferences, the airline industry has experienced significant transformation over the years. As one of
the leading players in this industry, Delta Airlines has played a pivotal role in shaping the landscape
of air travel. Delta Airlines, founded in 1928, has witnessed and adapted to the changing dynamics of
the industry. Through strategic expansions, acquisitions, and technological advancements, Delta has
established itself as a prominent global airline, connecting passengers to various destinations
worldwide. In Delta’s 2023 official guidance, it announced that its anticipated revenue growth
between 15 to 20 percent compared to 2022.
Customer satisfaction holds paramount importance in the service industry. In the airline industry,
it is also a key driver of success and sustainability, as satisfied customers contributes to a positive
brand image and are motivated to behave loyalty [1]. Customers tend to be satisfied when airlines
meet or exceed the service quality attributes that customers consider most important [2]. On the other
hand, unsatisfied passengers may reconsider choosing the same airline for future flights [3].
To analyze and improve customer satisfaction, this paper employs a combination of quantitative
and qualitative research methods. The quantitative analysis utilizes text mining techniques to examine
Proceedings of the 2nd International Conference on Financial Technology and Business Analysis
DOI: 10.54254/2754-1169/46/20230320
© 2023 The Authors. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0
(https://creativecommons.org/licenses/by/4.0/).
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customer reviews on Delta flights. This method allows for a comprehensive exploration of sentiments,
identifying trends, and extracting valuable insights from large volumes of customer data. Additionally,
the paper employs qualitative analysis, specifically utilizing a SWOT (Strengths, Weaknesses,
Opportunities, Threats) analysis to gain a holistic understanding of Delta's current position in terms
of customer satisfaction. According to the identified problems and chances, the study gives targeted
suggestions that would help Delta to improve customer satisfaction. In the end, the conclusions and
limitations of the study are given.
This study aims to provide a valuable example for companies in the airline industry interested in
studying consumer satisfaction using quantitative and qualitative methods. By sharing insights and
suggestions derived from the Delta Airlines case study, this paper intends to inspire and guide
industry stakeholders in their efforts to enhance customer satisfaction and improve overall service
quality.
2. Quantitative Research
2.1. Research Process
In this section of the quantitative study, a systematic process was conducted to gain insights into Delta
Airlines' customer satisfaction. As shown in Figure 1, the reviews and overall ratings along with other
variables were collected online. Then, the collected data was processed to ensure a consistent and
analytical format. To uncover patterns and gain insights, text mining techniques were employed.
Lastly, the results of the texting mining analysis were summarized and presented.
Figure 1: Research process.
2.2. Data Description, Process & Text Mining
The data used in the study was provided by Skytrax, an international airline rating organization known
for its justified evaluations of airlines worldwide. The study specifically focused on data from Delta
Airlines with periods from July 2015 to February 2023. Variables in the dataset included customer
ID, overall star rating, date, seat types, traveler types, country, and reviews.
The study leveraged R, a powerful programming tool, to perform data cleaning and text mining.
To ensure data quality and consistency, a rigorous process of data cleaning was undertaken. After
obtaining raw data from Skytrax, the first step was removing rows with missing values. A new feature
used to indicate the year of each review was created, allowing trend analysis. Moreover, seat types
and traveler types were categorized into four levels, enabling the smooth use of group function. Extra
words and non-essential signs were carefully removed from the review’s column.
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Text mining, an approach that extracts valuable and undiscovered information from unstructured
text, is a commonly recognized method to analyze reviews [4]. Sentiment analysis, as one of the
frequently used techniques of text mining, refers to the approach rooted in natural language
processing (NLP) which can reflect the emotional tone and evaluations behind the text. The study
mainly used sentiment analysis to explore insights [5]. From the start of the analysis, the text of
reviews was tokenized. To facilitate sentiment analysis, two widely recognized lexicons, namely the
Bing lexicon and the AFINN lexicon, were imported to calculate the sentiment score for these
tokenized words. By employing sentiment analysis techniques, this study gained valuable insights
into the emotional undertones of customer reviews.
2.3. Results
Table 1 illustrated the overall star ratings by year, with a range of ratings between 1 and 5. Feature
‘N’ represents the sample size (Except for additional explanations, the ‘N’ below all have the same
meaning). It can be seen that ratings displayed a decreasing trend. The lowest point of the mean
rating occurred in 2021, indicating the period of least customer satisfaction.
Table 1: Overall rating by year.
Year
N
Mean Rating
Median Rating
2015
200
4.7250
4
2016
234
4.9402
4
2017
226
4.2876
3
2018
341
3.3167
1
2019
366
3.6667
2
2020
107
4.2430
2
2021
299
2.6388
1
2022
467
2.9058
1
2023
28
3.1786
1.5
Table 2 showed the sentiment score results by year of sentiment analysis using the afinn lexicon.
Similar to the findings in Table 1, it becomes evident that the ratings exhibited a noticeable declining
trend. Particularly noteworthy is that the lowest point in the mean score occurred in 2021, indicating
the lowest level of customer satisfaction during the analyzed period.
The decline in customer satisfaction in 2021 can be attributed to the impact of the Covid-19
pandemic. Although the pandemic began in early 2020, customer satisfaction levels were not
significantly affected at that time due to the regulatory limitations on public transportation and
widespread fear of contracting the virus. In contrast, by 2021, people had started to recover normal
activities while the virus remained a concern. To ensure maximum safety, governments implemented
various policies that added inconvenience to the travel process, including ticket booking, security
checks, and boarding procedures. Therefore, it is crucial for Delta to have a quick response to the
latest regulations and processes, develop the ability to respond to emergencies, and provide up-to-
date information to customers.
Table 2: Sentiment score by year.
Year
N
Median Score
Mean Score
2015
1620
1
0.2901
2016
1889
1
0.2721
2017
1881
1
0.2068
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Table 2: (continued).
2018
2553
-1
-0.1817
2019
3077
-1
-0.0396
2020
880
1
0.2920
2021
2222
-1
-0.2849
2022
3676
-1
-0.1899
2023
236
-1
-0.1568
The study utilized the Bing lexicon to determine the word valence for each year. Based on the
word valence results, negative word ratio and positive word ratio were calculated, as presented in
Table 3. The analysis revealed that the negative word ratio was consistently greater than the positive
word ratio each year. Notably, the negative word ratio exhibits an increasing trend over time,
suggesting a growing dissatisfaction among customers.
Table 3: Word valence by year.
Year
Negative Word Ratio
Positive Word Ratio
2015
52.12%
47.88%
2016
54.47%
45.53%
2017
55.13%
44.87%
2018
66.76%
33.24%
2019
65.03%
34.97%
2020
56.30%
43.70%
2021
68.13%
31.87%
2022
66.36%
33.64%
2023
62.56%
37.44%
The study utilized the AFINN lexicon to calculate the sentiment scores for four different cabin
classes, as shown in Table 4. The results indicated that the Economy Class received the lowest
sentiment score. A noteworthy finding emerged from the data: the sentiment score of the First Class
is lower than both the Business Class and Premium Economy. This presented a significant concern,
as customers who are willing to pay for the best services did not appear to receive the expected level
of service quality. Given that the First-Class segment typically generates the highest profits in the
airline industry, it becomes imperative for Delta to prioritize addressing this issue. By focusing on
improving the service quality and experience provided in the First Class, Delta can enhance customer
satisfaction and retain high-income customers.
Table 4: Sentiment score by cabin classes.
Cabin Classes
Sentiment Score
N
First Class
0.0802
183
Business Class
0.1189
128
Premium Economy
0.0953
174
Economy Class
-0.0483
1783
Using the AFINN lexicon, the study computed sentiment scores for four distinct cabin classes, as
demonstrated in Table 5. The analysis revealed that the Solo Leisure category obtained the highest
sentiment score, while the Family Leisure category received the lowest sentiment score. Therefore,
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Delta should pay more attention to passengers who travel with their families and ensure the provision
of dedicated care services for children and older passengers.
Table 5: Sentiment score by travel types.
Traveler Types
Sentiment Score
N
Business
-0.0201
433
Couple Leisure
-0.0403
531
Family Leisure
-0.0541
548
Solo Leisure
0.0243
756
3. SWOT Analysis
This section conducts a SWOT analysis of Delta Airlines' customer satisfaction, in which strengths,
weaknesses, opportunities, and threats are assessed. SWOT analysis is an essential tool for
performance evaluation, resource allocation, and strategic planning in various industries and
organizations [6, 7]. With SWOT analysis, the internal and external factors that affect Delta’s
customer satisfaction are undiscovered, serving as a foundation of suggestions.
3.1. Strengths
Delta has launched many programs to cultivate customer loyalty and increase customer satisfaction.
The SkyMiles program has become an important part of Delta’s customer retention strategy. The
program is designed to incentivize frequent flyers and provide plenty of benefits. At its core, the
program reward customers for their travels based on miles, membership level, and cabin class. Delta
ensures customers enjoy meaningful rewards including flight upgrades, free tickets, hotel stays, etc.
Besides, Delta has made efforts to differentiate its strategy. Delta One Suite program offers an
extremely exclusive and luxurious experience for premium travelers. Customers who are willing to
pay for this program are provided with fully enclosed suites, lie-flat beds, carefully tailored services,
and premium amenities. Delta Comfort Plus is a differentiated cabin experience available on select
flights, offering extra legroom, priority boarding, and enhanced services. This program caters to
customers who cannot afford First Class and Business Class but seek to add comfort with an extra
moderate price.
Delta Airlines has placed a strong emphasis on training customer service. It invests invest about
$500,000 annually in employee training. Moreover, Delta Cares is a program that helps customers
who seek special needs, such as customers with disabilities or people requiring medical assistance.
Delta is famous for its commitment to exceptional customer service. It was awarded as the No.1
airline among North American airlines by J.D. Power in 2021 [8]. Delta was honored for its
professionalism, care, and humanity, which shows its customer-centric approach is effective. Focus
on sustainability has made significant strides in environmental sustainability, including taking
initiatives to decrease greenhouse gas emissions, invest in fuel-efficient development, and implement
recycling programs. These efforts can enhance Delta’s reputation and customer satisfaction.
3.2. Weaknesses
Like many airlines, Delta Airlines has to face operational challenges, which significantly affect
customer satisfaction. These challenges include but are not limited to delays, cancellations, and
baggage loss. Factors such as severe weather conditions, flight maintenance, labor changes, and air
traffic congestion can lead to disruptions in flight schedules. Combined with the above quantitative
analysis, it can be seen that delay is a serious problem that needs to get more attention. As a leading
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airline company based in the USA, Delta operates numerous destinations and routes, bringing huge
challenges to maintaining consistently high service quality. Due to differences in local management,
infrastructure as well as resource limitation, and many other factors, customers may receive
inconsistent in-service experience. Exceptional or subpar experiences may happen in the same
situation. The inconsistency in service can lead to customer dissatisfaction and harm the brand image.
Although Delta has an extensive domestic network, its international coverage is limited compared
to its strong competitors. Members or frequent users may feel inconvenienced because they cannot
have seamless connectivity. The limitation in international coverage potentially affects customer
satisfaction. Compared to many competitors such as United Airlines, JetBlue, Southwest Airlines,
Spirits Airlines, and Frontier Airlines, Delta encounters a weakness regarding price, which tends to
be higher. As customers pay a higher price for Delta’s flights, they naturally expect a superior level
of service to justify the price. This adds pressure on Delta’s services. Failing to match these elevated
expectations may result in dissatisfaction and decrease customer loyalty.
3.3. Opportunities
Adopting new technologies presents one of the biggest opportunities for Delta to improve customer
satisfaction. By leveraging Artificial Intelligence (AI) tools and data analytics, Delta is able to
improve its performance in customer satisfaction. For example, the chatbots based on AI technologies
and virtual assistance enable Delta to provide real-time support and realize cost efficiency in the long
run. Furthermore, Delta utilized data analytics to gain insights into customer preferences and patterns.
Also, pain points and trends can be identified, which allows Delta to address customer concerns,
refine services and make informed decisions to improve customer satisfaction. Combined with the
result of quantitative analysis that passengers who took First Class did not give relatively positive
feedback, providing premium personalized services should be considered seriously by Delta.
3.4. Threats
The economy is an important factor that affects customer satisfaction in the airline industry. During
periods of economic downturns and recessions, businesses and individuals tend to reduce living
expenditures, including travel, which would lead to reduced demands for flights, lower profitability,
and the incapability of maintaining high-quality service. In addition, fluctuations in fuel prices can
impact operating costs and add pressure on the cost of maintenance of service quality, thereby
affecting customer satisfaction.
Moreover, intensive competition is also a considerable threat. The airline industry is characterized
as a fiercely competitive industry, with airlines constantly vying for market share. Delta faces
challenges from competitors, especially low-cost carriers who offer more affordable ticket prices.
Once those competitors who target price-sensitive segments devote themselves to improving their
quality of services, the dissatisfaction may increase for Delta’s members and potential customers.
Regulatory and policy also play a crucial role in customer satisfaction in the airline industry [8].
They can impact Delta’s customer satisfaction in many aspects. One common area is security
measures. Since the increasing security threats, governments may issue stricter regulations regarding
security procedures. Even if those regulations aim to ensure the safety of passengers, part of
passengers may feel inconvenienced and troublesome, which leads to dissatisfaction. Changes in air
traffic controls can affect airlines as well. Delta may adjust its flight plans, coordinate with air traffic
control authorities and modify its operational strategies. Any changes may cause delay or cancellation,
which results in a less seamless experience.
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4. Suggestion
Based on the above results from quantitative analysis and qualitative analysis, the study provides
suggestions that Delta should consider adopting, in order to solve current problems and effectively
improve customer satisfaction.
Utilizing Technology to Reduce the negative impact of Delays: Delta should leverage technology
solutions to minimize flight delays and maximize punctuality. Implementing advanced prediction
systems and real-time monitoring platforms is necessary, in order to identify problems in time and
take proactive measures to mitigate delays [9]. Technology can also be used to ease passengers'
anxiety while waiting for a delayed flight. For example, passengers can play games in Delta’s
Application to earn mileage points, or passengers can have fun chatting with AI.
Establishing Uniform Service Standards: Delta should enforce its uniform service standards across
all airports and service departments to ensure consistent and high-quality service. Regular training
for employees should emphasize customer-centric vision, such as understanding and anticipating
customer needs, active listening, and empathy. Effective communication training is crucial to ensure
clear message delivery throughout the journey. Establishing communication channels for employees
to raise questions and share their experiences should be considered by Delta. Thus, staff in different
places could discuss together on specific platforms and have a better service solution towards tricky
circumstances.
Broadening Global Networks and Partnerships: Delta should actively seek partnerships and
alliances with more airlines to expand its global network and offer a wider range of international
flight choices to customers. Collaborations with more partners will be able to provide customers with
seamless connections, more destination options, and an improved travel experience for passengers.
By providing convenient and comprehensive travel solutions, Delta will enhance customer
satisfaction and loyalty continuously.
Commitment to Sustainability and ESG: Delta should continue its focus on sustainability and
invest in Environmental, Social, and Governance (ESG) initiatives. This includes adopting fuel-
efficient aircraft, implementing waste reduction programs, and promoting responsible practices
throughout the organization [10]. By prioritizing sustainability, Delta demonstrates its commitment
to environmental stewardship and social responsibility, appealing to customers who value eco-
friendly and socially conscious travel options.
Quick Response to Policy Changes: The most important thing for Delta is to make customers
understand that the airline can only comply with the policy changes, but it will take remedial measures
to the maximum extent possible to reduce the trouble caused to passengers. Delta should inform
passengers and members the first time when policy changes, addressing any concerns or questions
they may have. Timely notification about policy updates, travel restrictions, or operational changes
allows customers to plan in advance and helps alleviate any potential frustration or confusion.
Additionally, providing alternative solutions or extra credits to make up for the inconvenience that is
brought up by policy changes.
Tailor Amenities and Services for First Class Customers: Delta should continuously evaluate and
refine the amenities and services provided in the First Class to exceed customer expectations.
Upgrading seating comfort, diversifying gourmet menus, offering concierge assistance and dedicated
onboard attendants are key solutions that Delta should consider. By offering unique and differentiated
experiences, Delta can enhance the perceived value of First Class and leave a lasting impression on
passengers.
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5. Conclusion
In conclusion, this paper has focused on enhancing customer satisfaction in the airline industry, with
a specific case study of Delta Airlines. The reviews from Skytrax were analyzed with the appliance
of sentiment analysis techniques. Also, a SWOT analysis was given elaborately. Based on the above
analysis, targeted suggestions were provided to Delta, including leveraging technology to reduce the
negative impact of delays, establishing uniform service standards, broadening global networks and
partnerships, committing to sustainability and ESG initiatives, and ensuring quick responses to policy
changes.
The limitations of this study include the reliance on only one platform that provides publicly
available data, which may not capture the full range of customer experiences, as well as the subjective
nature of sentiment analysis. Additionally, the study focused on Delta Airlines as a single case study,
and the insights and findings may not be directly applicable to other airlines or industry contexts.
Moreover, the SWOT analysis may oversimplify complex situations and fail to capture the nuance
and interdependencies between factors. Even though, the insights and suggestions derived from this
study can serve as an example and inspiration for companies in the airline industry interested in
studying customer satisfaction.
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