プロジェクトストーリー

Project team established

"Hey, why don't you give it a try?"
The project to develop the next-generation aircraft began with a single comment from the head of the design department.
At the time, our company was developing various concepts for aircraft to follow the US-2, but none of them ever made it beyond the theoretical realm, which was frustrating. Furthermore, a considerable amount of time had passed since the development of the US-2, and any further gap would risk making it difficult to transfer our technology.
Therefore, a project team of five people was established, mainly consisting of experienced aircraft design and manufacturing personnel and ambitious young people. The goal was to accelerate the review process and pass on technology through development. Although it was called a project team, it started small at the time, with members conducting research in between their regular duties.
The basic principle of this team is: "It has no value unless you build it and fly it. By building and flying even a small model, you can accumulate technology and explore market needs. You must not hesitate to show it to others."
This fundamental policy is still followed today, and a system has been established in which designers are involved in the entire process from conception to manufacturing and testing. Partial manufacturing and testing are constantly repeated within the company, and flight tests are always conducted several times a year.

XV-S Production and Testing

When the project team was established, VTOL ^* technologies such as eVTOL and flying cars were attracting attention as technologies for opening up a new aircraft future.
On the other hand, we are a company that has specialized in the design and development of fixed-wing aircraft, and we did not have specific knowledge about the impact of VTOL fixed-wing aircraft on weight, aerodynamics, control, etc., and how to countermeasure them. Therefore, as the team's first project, we decided to develop a small unmanned aerial vehicle (XV-S) with the aim of gaining knowledge related to VTOL technology.
The XV-S was tested in various stages for three years from 2015, and finally achieved a flight that transitioned from vertical takeoff to horizontal flight and then to vertical landing. Although it was a simple verification using a small unmanned aerial vehicle, through this research, we were able to discover several challenging technical issues unique to VTOL aircraft.
Since it is extremely difficult to commercialize the latest product in light of the cost of solving these problems in light of market needs, we have decided to put the exploration of VTOL technology on hold.
On the other hand, we were able to acquire a lot of lightweight structures and system design/manufacturing technologies, so we started a new concept following the XV-S by utilizing these technologies.

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  VTOL: Vertical Take-Off and Landing

XU-S Production and Testing

Through the research on the XV-S, the project team shifted its focus to developing aircraft primarily focused on CTOL ^*(Contact-to-Loop) fixed-wing aircraft.
The first aircraft we designed and manufactured was the XU-S. We envisioned a future aircraft that would handle wide-area surveillance and observation missions as well as information and communication at medium to high altitudes. The XU-S was developed as a demonstrator that could fly for extended periods while weighing about the same as a multirotor, in order to delve deeper into specific market needs through various flight demonstrations.
After commencing design work in April 2018, the aircraft was completed and its maiden flight conducted in October 2019, achieving its target of approximately four hours of long-duration flight the following year. Achieving this long flight time involved facing various challenges, including weight reduction down to the gram and designing efficient automatic control systems. Numerous fine-tuning adjustments were made late into the night, even during business trips for flight testing. This experience reaffirmed the strength of this project team: the ability of the designers to handle everything from manufacturing to testing.
Furthermore, the long-duration flight tests generated a lot of feedback, confirming that the solution (infrastructure = aircraft) is immature compared to the potential market needs.

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  CTOL: Conventional Take-Off and Landing

XU-S Mission Demonstration

Following the long-duration flight tests in 2020, we received various requests, and over the two years from 2020 to 2021, we conducted three major demonstration tests.
The first phase involved environmental observation tests on Awaji Island, the second phase involved radio wave propagation characteristics tests on Sado Island, and the third phase involved aerial photography tests of marine debris on Tsushima Island.
Our company designed and manufactured modules for mounting mission equipment tailored to each test objective, and improved the system with each test. Ultimately, we equipped the aircraft with satellite communication equipment and achieved the first Level 3 flight (unassisted beyond visual line of sight flight in an uninhabited area) in Japan, using airports with regular air service as takeoff and landing bases.
During these demonstration tests, there were instances where power supply problems or communication issues nearly resulted in the loss of the aircraft, but in each case, safety design prevented disaster. These demonstration tests provided a wealth of experience that will be invaluable in designing future autopilot systems with high safety and reliability.

XU-L Production and Testing

Through the mission demonstration of the XU-S, we recognized that there is a definite market need that goes beyond the weight, distance, and time that conventional drones can carry. From a practical standpoint, it is essential that the drone can transport at least the weight of one person and possess the reliability and safety equivalent to that of a manned aircraft.
To get closer to this goal, we have selected and introduced an existing aircraft (Rans S-6, USA) as a testbed for system development and mission equipment verification for future medium to large-sized aircraft development.
The XU-L was also used in joint research with Yamaha Motor Co., Ltd., and our company was in charge of design changes due to engine installation, flight permit applications, and test operations. We faced a vibration environment that was incomparable to the XU-S and stricter safety standards, and there were many times when things did not go as planned, but we overcame each challenge by analyzing the cause each time and accumulating countermeasures. The sense of accomplishment when we successfully completed the flight tests after much hard work has been a great driving force for all the members involved on site.

XU-M Production and Testing

The technology to safely and automatically take off and land Amphibian in the open ocean is a realm that even our flagship amphibian aircraft the US-2, has yet to reach. The XU-M was designed and manufactured for research into automatic takeoff and landing technology in order to expand the range of applications for Amphibian, including the US-2.
The hull shape design incorporates the technology we have cultivated in Amphibian development, and the system design is based on the technology obtained up to the XU-S. This aircraft made the most of our team's rapid prototype manufacturing capabilities, achieving the transition from design to rollout in a remarkably short period of about six months.
After conducting a demonstration flight at the first Drone Summit in 2022, the XU-M underwent multiple automatic water landing tests in the waters surrounding our company. Although there were some hard landings due to insufficient adjustment of the automatic water landing control, we obtained a lot of data, including the mistakes, that will be useful for future development of automatic water landing technology.

XU-L OPV Testing

The XU-L was equipped with an OPV ^* control system consisting of FCC^* and actuators, and the pilot switched from manual control to automatic piloting in the air.
Based on the purely domestic FCC, it is equipped with a newly designed and developed one that is tailored to the flight content and system of the XU-L. In addition to the safety design of the system, including FCC, we achieved a manned test flight after conducting various confirmation tests on the ground.
With the achievement of this test, we feel that we are one step closer to developing a next-generation aircraft equivalent to a manned aircraft, which we envisioned from the beginning of the project team's establishment. We will continue to use XU-L as a testbed to conduct various technology demonstrations.

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  FCC：Flight Control Computer

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  OPV：Optionally Piloted Vehicle

XU-MⅡ Production and Testing

We designed and manufactured a 1/5 scale model of the twin-hulled unmanned Amphibian demonstrator aircraft currently under development as part of the K Program's research and development project, "Construction of an Ocean Observation, Monitoring, and Survey System Using Unmanned Aircraft for Sea and Air."
We are making significant improvements by leveraging the knowledge gained from the manufacturing and testing of the XU-M.
By changing the hull structure from a semi-monocoque to a full monocoque, we achieved both weight reduction and maximized internal volume simultaneously.
・XU-L OPV Testing We have incorporated the FCC ^* used in our previous project to improve the system's security.
During fiscal year 2025, we conducted multiple flight tests and achieved automatic water landing, which was not accomplished with the XU-M. We will continue to utilize this technology in various research activities, including automatic water landing, and will apply the acquired technology to the K Program and other aircraft models.

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  FCC：Flight Control Computer