Delta Air Lines Data Engineer Interview Questions + Guide in 2025

Delta Air Lines is a major American airline that strives to provide exceptional service and operational excellence while leveraging technology to enhance customer experience.

As a Data Engineer at Delta Air Lines, you will play a pivotal role in designing, building, and optimizing data pipelines and architectures that support the airline's data-driven decision-making. Your key responsibilities will include developing and maintaining robust ETL processes, managing data integration from various sources, and ensuring data quality and accessibility for analytics and reporting. The role requires proficiency in cloud technologies, particularly AWS and Azure, as well as experience with data warehousing solutions.

To thrive in this position, you should possess strong programming skills in languages such as Python or SQL, alongside a solid understanding of data modeling, database management, and big data technologies. A great fit for this role is someone who is detail-oriented, analytical, and able to work collaboratively in a fast-paced environment. Familiarity with AWS Glue and other data processing tools will be highly advantageous.

This guide will help you prepare for your interview by equipping you with insights into the key competencies and expectations of a Data Engineer at Delta Air Lines, ultimately boosting your confidence and performance during the selection process.

The interview process for a Data Engineer position at Delta Air Lines is structured to assess both technical skills and cultural fit within the organization. The process typically unfolds in several key stages:

1. Initial Contact

The journey begins with an initial contact, often through a text message or email, where candidates are informed about their selection for an interview. This stage may take some time, as candidates have reported waiting up to a month for this communication.

2. Technical Interview

The technical interview is usually conducted by a panel of interviewers, including the hiring manager and other technical team members. This interview focuses on the candidate's technical background, experience with data engineering tools, and cloud platforms such as AWS and Azure. Expect in-depth questions that may include live coding exercises and discussions about implementing data pipelines. Candidates should be prepared to demonstrate their knowledge of AWS Glue and other relevant technologies.

3. Behavioral Interview

Following the technical assessment, candidates may participate in a behavioral interview. This round aims to evaluate how well candidates align with Delta Air Lines' values and culture. Interviewers will likely ask about past experiences, teamwork, and problem-solving approaches to gauge interpersonal skills and adaptability.

4. Final Panel Interview

In some cases, a final panel interview may be conducted, where candidates meet with multiple team members to further assess their fit for the role. This round may include a mix of technical and behavioral questions, providing a comprehensive evaluation of the candidate's capabilities and potential contributions to the team.

As you prepare for your interview, it's essential to familiarize yourself with the types of questions that may arise during this process.

Here are some tips to help you excel in your interview.

Understand the Technical Landscape

As a Data Engineer at Delta Air Lines, you will likely be working with cloud technologies such as AWS and Azure. Familiarize yourself with the specific tools and services offered by these platforms, particularly AWS Glue, as it has been highlighted in previous interviews. Be prepared to discuss your experience with data pipelines, ETL processes, and how you have utilized these technologies in past projects.

Prepare for Live Coding Challenges

Expect to encounter live coding exercises during your interview. Practice coding problems that are relevant to data engineering, such as building data pipelines or transforming datasets. Use platforms like LeetCode or HackerRank to sharpen your skills in Python, SQL, and any other relevant programming languages. Being able to articulate your thought process while coding will demonstrate your problem-solving abilities and technical expertise.

Showcase Your Experience

Be ready to discuss your past experiences in detail, particularly those that relate to data engineering. Prepare specific examples that highlight your technical skills, problem-solving capabilities, and how you have contributed to previous projects. Use the STAR (Situation, Task, Action, Result) method to structure your responses, ensuring you convey the impact of your work clearly.

Engage with the Interview Panel

Interviews at Delta Air Lines may involve a panel of interviewers, so be prepared to engage with multiple people. Make eye contact, address each panel member when responding, and be attentive to their questions. This will not only show your interpersonal skills but also your ability to collaborate in a team environment, which is crucial in a data engineering role.

Follow Up Professionally

Given the feedback from previous candidates about the hiring process, it’s important to follow up after your interview. Send a thank-you email to express your appreciation for the opportunity and reiterate your interest in the position. This can help keep you on their radar and demonstrate your professionalism.

Embrace Delta's Culture

Delta Air Lines values teamwork, innovation, and customer service. Reflect on how your personal values align with the company’s culture and be prepared to discuss this during your interview. Show enthusiasm for the role and the company, and be ready to explain how you can contribute to their mission of providing exceptional service through data-driven decisions.

By following these tips, you will be well-prepared to make a strong impression during your interview for the Data Engineer role at Delta Air Lines. Good luck!

In this section, we’ll review the various interview questions that might be asked during a Data Engineer interview at Delta Air Lines. The interview will focus on your technical expertise, particularly in cloud technologies, data pipeline implementation, and your experience with data management tools. Be prepared to discuss your past projects and how you have utilized various technologies to solve data-related challenges.

Technical Skills

1. Can you explain your experience with AWS Glue and how you have used it in your projects?

Delta Air Lines is interested in your hands-on experience with AWS Glue, as it is a critical tool for data integration and ETL processes.

How to Answer

Discuss specific projects where you utilized AWS Glue, focusing on the challenges you faced and how you overcame them. Highlight your understanding of its features and benefits.

Example

“In my previous role, I used AWS Glue to automate the ETL process for our data warehouse. I set up crawlers to catalog our data sources and created jobs to transform and load data into Amazon Redshift. This reduced our data processing time by 30% and improved data accessibility for our analytics team.”

2. Describe how you would implement a data pipeline from scratch.

This question assesses your understanding of data pipeline architecture and your ability to design efficient data workflows.

How to Answer

Outline the steps you would take to design and implement a data pipeline, including data ingestion, transformation, and storage. Mention any tools or technologies you would use.

Example

“To implement a data pipeline, I would start by identifying the data sources and the required transformations. I would use Apache Kafka for real-time data ingestion, followed by Apache Spark for processing the data. Finally, I would store the processed data in a cloud-based data warehouse like Snowflake for easy access by analytics teams.”

3. What cloud platforms have you worked with, and how do they compare?

Understanding your experience with different cloud platforms is crucial, as Delta Air Lines may utilize multiple services.

How to Answer

Discuss your experience with various cloud platforms, focusing on their strengths and weaknesses. Be specific about the services you used and the context in which you applied them.

Example

“I have worked extensively with both AWS and Azure. While AWS offers a broader range of services and is more mature in terms of data engineering tools, I found Azure’s integration with Microsoft products to be beneficial for certain projects. For instance, I used Azure Data Factory for orchestrating data workflows in a project that required seamless integration with Power BI.”

4. How do you ensure data quality and integrity in your data engineering processes?

Data quality is paramount in data engineering, and Delta Air Lines will want to know your approach to maintaining it.

How to Answer

Explain the methods and tools you use to validate and clean data. Discuss any frameworks or best practices you follow to ensure data integrity.

Example

“I implement data validation checks at various stages of the data pipeline, using tools like Great Expectations to automate data quality checks. Additionally, I establish clear data governance policies to ensure that all team members understand the importance of data integrity and follow best practices.”

5. Can you discuss a challenging data engineering problem you faced and how you resolved it?

This question allows you to showcase your problem-solving skills and technical expertise.

How to Answer

Choose a specific challenge, describe the context, the steps you took to resolve it, and the outcome. Focus on your analytical and technical skills.

Example

“In a previous project, we faced performance issues with our data pipeline due to high data volume. I analyzed the bottlenecks and discovered that our transformation jobs were not optimized. I refactored the code to use partitioning and parallel processing, which improved the pipeline’s performance by 50% and ensured timely data availability for our stakeholders.”