Initiatives in the Aerospace Business

Research on Obstacle Detection Systems for Ensuring Helicopter Flight Safety

Helicopters possess distinctive capabilities such as hovering and the ability to take off and land without requiring a runway, unlike fixed-wing aircraft. These traits are crucial for rescue operations in disaster-stricken areas and mountainous terrain, where tasks in confined spaces surrounded by obstacles such as trees, transmission towers, and cliffs are often required. In areas surrounded by obstacles, factors such as changing wind direction and reduced visibility can inadvertently lead to unintended approaches toward these obstacles. In the worst-case scenario, there’s a possibility of contact and even a crash, highlighting the increased awareness of the hazards posed by obstacles.
Various safety devices are incorporated into aircraft, including helicopters, enabling them to detect and avoid a range of hazards. However, they may not cover all potential risks. For this reason, SUBARU is actively engaged in the research and development of obstacle detection systems as part of efforts to eliminate collision accidents.
Obstacle detection systems utilize sensors to detect surrounding obstacles in real-time, particularly in situations with narrow spaces or potential collision risks during adverse weather or poor visibility conditions. They alert the pilot through display and auditory warnings, providing assistance for safe avoidance maneuvers. In the future, the aim is to achieve pilot assistance that enables automatic maneuvering to avoid detected obstacles.

Obstacle Detection System

Research on Lightning Avoidance Systems for Aircraft and Next-Generation Mobility

In recent years, there has been a growing emphasis on the development of advanced air mobility projects, such as flying cars and drone deliveries, contributing to a potential increase in airborne mobility. However, as cars also take to the skies, approaching thunderclouds can lead to an increase in electric fields, raising the potential for lightning strikes. Modern aircraft are engineered to maintain safe flight even in the event of lightning strikes. Nevertheless, the areas impacted by lightning strikes necessitate repairs, prompting the pursuit of technologies that either mitigate damage or prevent lightning strikes entirely. SUBARU is actively engaged in research aimed at avoiding lightning strikes, which can also be applied to advanced air mobility solutions.
Weather data may detect the distribution of thunderclouds, but accurately predicting where lightning will strike remains challenging. As a result, there is a growing need for aircraft to possess systems capable of preemptively detecting and avoiding lightning. SUBARU partnered with Japan Aerospace Exploration Agency (JAXA) to conduct experiments and analyses on discharge characteristics concerning aircraft model simulations. This research revealed the potential for variations in the susceptibility of lightning strikes based on the direction of lightning, the aircraft’s angle, and the generation of static electricity on the aircraft. In addition, an algorithm has been developed that uses sensor information installed on the aircraft to predict lightning strikes on the aircraft’s surface. Moving forward, the focus will be on verifying this algorithm and refining it to offer supportive information to pilots. Additionally, the aim is to develop and offer aircraft designed to avoid lightning strikes by controlling the aircraft’s state, encompassing advanced air mobility solutions.

Steps from Lightning Prediction to Lightning Avoidance

Proposed Revision of International Standards for Collision Avoidance of Unmanned Aircraft

Small unmanned aircraft, commonly referred to as drones, and larger, medium-sized unmanned aircraft are already being used widely in the agricultural sector and other areas, and are also expected to be used for transporting goods during disasters, searching for people in distress, and for logistics infrastructure. However, there have been reports of near misses between unmanned aircraft and manned aircraft such as helicopters in Japan, and how to avoid collisions with other aircraft is an urgent issue toward the safe use of these unmanned aircraft. Collision avoidance is also an indispensable technology for achieving flight outside of line-of-sight and flight over third-party entities, which are key elements for the social implementation of unmanned aircraft.
SUBARU, together with Japan Radio Co., Ltd. and ACSL Ltd. proposed the revision of international standards for the technical operation of collision avoidance procedures between unmanned aircraft and other aircraft, or between unmanned aircraft, based on the results of development in the New Energy and Industrial Technology Development Organization (NEDO)’s Drones and Robots for Ecologically Sustainable Societies project (DRESS project), and this revised standard was adopted and issued by the International Organization for Standardization (ISO).
With the standardization of collision avoidance procedures, systems to detect and avoid other aircraft as a necessary means of avoidance, as well as standardization of testing methods, are expected to further ensure air safety.

Details of International Standard Revision

ISO 21384-3, first published in November 2019, standardized operational procedures for unmanned aircraft, but did not specify procedures for avoiding collisions with other aircraft or between unmanned aircraft.
In the new revision, Concept of Operations (CONOPS) for collision avoidance was added as a chapter, which defines the basic procedure consisting of six steps: object detection, target recognition, avoidance maneuvers, confirmation of avoidance results, return to the original route, and flight on the original route. Going forward, this international standard will serve as a guideline for unmanned aircraft, which will follow these six steps and take uniform avoidance actions.