This project focused on developing an unmanned system capable of operating both in the air and underwater. The concept was motivated by the need to access marine environments efficiently for environmental observation, water sampling, and pollution detection. A major engineering challenge was combining the requirements of aerial flight and underwater operation within a single platform. I worked on the mechanical and aerodynamic development of the vehicle and investigated how its configuration could support operation in both environments. The system geometry and mechanical components were designed and developed according to the requirements of aerial and underwater operation. Aerodynamic and fluid-dynamic behaviour was analyzed to evaluate the vehicle under relevant operating conditions. The propulsion and structural arrangement had to account for the very different physical properties of air and water. Particular attention was given to maintaining a practical configuration while providing the mobility required for scientific sampling missions. The system was designed to support water-quality investigations by reaching selected locations and collecting samples for subsequent analysis. The project therefore combined UAV engineering with environmental monitoring and marine exploration requirements. Developing the platform required multidisciplinary work across aerodynamics, mechanical design, fluid dynamics, control concepts, and environmental applications. The project also contributed to a patented concept for a vertical flying robot capable of underwater movement and strengthened my interest in autonomous systems for scientific exploration.