Effective maritime anti-submarine operations are crucial for national security. While current UAV’s primarily rely on fixed-wing for limited-range scanning, the concept of aquatic UAV with vertical takeoff capabilities carrying sonar for prolonged surveillance presents a novel approach. Therefore, this paper introduces a new tilt-body style VTOL aerial vehicle, which features a simple body structure devoid of complex tilt mechanisms, offering advantages such as rapid takeoff and landing. To adapt to waterborne takeoff and achieve an efficient vertical takeoff process, a hull optimization design algorithm is proposed, transforming the tilting body takeoff motion into a process of submerged volume variation. Design points are selected to calculate the low-head moment values during takeoff, optimizing based on average and extreme values, with the parked state volume as a constraint for optimization. Integration of PID takeoff controllers with two-phase fluid simulation method is conducted to analyze the vehicle’s behavior during waterborne vertical take-off. The results confirm the effectiveness of the optimized design. The research contributes to the advancement of aquatic VTOL aerial vehicles design and simulation methodologies, offering insights into optimizing performance and enhancing operational capabilities in various mission scenarios.