Chinnasami Sivaji.et.al / REST Journal on Advances in Mechanical Engineering, 4(2), June 2025, 1-14 Copyright@ REST Publisher 1 REST Journal on Advances in Mechanical Engineering Vol: 4(2), June 2025 REST Publisher; ISSN: 2583-4800 (Online) Website: https://restpublisher.com/journals/jame/ DOI: https://doi.org/10.46632/jame/4/2/1 The TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) Method for Aircraft Type Selection *Chinnasami Sivaji, Devipriya Mani, M. Ramachandran, Ramya Sharma REST Labs, Kaveripattinam, Krishnagiri, Tamil Nadu, India. *Corresponding Author Email: chinnasami@restlabs.in Abstract: Aircraft type Choice is flight A for companies Make important decisions process, in which Includes assessment various factors such as capacity, revenue potential, customer expectations, maintenance costs, and more. Technique for Priority Ranking by Similarity of Ideal Solution (TOPSIS) method provides a systematic approach to compare and rank different aircraft types based on multiple criteria. This abstract explores the application of the TOPSIS method in aircraft type selection, highlighting its benefits in considering diverse objectives and facilitating a more informed decision-making process. By assigning weights to criteria and comparing the alternatives to an ideal solution, the TOPSIS method helps airlines identify the most suitable aircraft type that aligns with their requirements and objectives. The abstract emphasizes the importance of accurate data and periodic reassessment due to evolving market conditions and technological advancements. Ultimately, the TOPSIS method assists airlines in making optimal decisions that optimize operational efficiency, customer satisfaction, and financial performance in aircraft type selection. Selecting the right type of aircraft is a crucial decision that involves a careful evaluation of various factors and considerations. Whether it's for commercial airlines, private aviation, military operations, or cargo transportation, choosing the appropriate aircraft type is essential to meet specific requirements, optimize performance, ensure safety, and achieve operational efficiency. The process of aircraft type selection involves a comprehensive analysis of multiple parameters, such as mission profile, range, payload capacity, operational costs, environmental considerations, regulatory requirements, and technological advancements. It requires a thorough understanding of the intended purpose, operational constraints, and long-term objectives. For commercial airlines, factors like passenger capacity, range capability, fuel efficiency, and passenger comfort play a vital role in selecting the right aircraft type. Airlines need to consider market demand, route network, and the ability to maximize revenue while minimizing operating expenses. The research on aircraft type selection holds significant importance in the aviation industry due to the following reasons: Operational Efficiency: The selection of the right aircraft type can significantly impact operational efficiency. By identifying the most suitable aircraft for a specific mission profile, airlines, private operators, and military organizations can optimize fuel consumption, reduce operating costs, and enhance overall performance. Research in this area helps to develop methodologies, models, and decision-support tools that enable informed and data-driven aircraft selection processes. Safety and Security: The safety and security of passengers, crew, and cargo are paramount in aviation. Choosing the appropriate aircraft type involves considering safety features, maintenance requirements, compliance with regulatory standards, and the ability to handle emergencies. Research in aircraft type selection contributes to the identification of aircraft that meet the highest safety standards, reducing the risk of accidents and ensuring the secure transportation of people and goods. Market Competitiveness: In the commercial aviation sector, staying competitive in a rapidly evolving market is crucial. Airlines need to select aircraft that align with market demand, passenger preferences, and route networks. Research in aircraft type selection aids in understanding market dynamics, forecasting future trends, and identifying aircraft that offer the best balance between capacity, range, fuel efficiency, and passenger comfort. It enables airlines to make informed decisions that enhance their competitiveness and profitability. We will be use TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) in this study, which is a research approach that gives TOPSIS research methods because it enables researchers to make informed and objective decisions in a multicriteria environment. Its quantitative and transparent approach, consideration of positive and negative aspects, simplicity, flexibility, and robustness make it a valuable tool for various research disciplines, facilitating systematic analysis and comparison of alternatives. Alternative Parameters taken as Boeing78C, Boeing79L, Airbus321, Airbus32C, Airbus320, Airbus319. Evaluation Parameters taken as Capacity, Revenue, Customer expectation, Maintenance Cost.