Currently, much attention is paid to active debris removal (ADR) missions by small, cost-effective satellites. ADR missions using thrusters from a high altitude to reentry consume considerable fuel. In this type of mission, the propulsion system for a satellite takes up a great deal of space. It is difficult for a small satellite to accommodate a large-scale propulsion system. This study introduces a hybrid reentry strategy for rapidly deorbiting large debris using small satellites. The proposed strategy consists of two phases, one using electric propulsion and the other actively using aerodynamic drag. In both phases, optimal attitude path planning is important and can be carried out with the attitude control capabilities of a small satellite with low capability. This study first developed an aerodynamic database (ADDB) by rigorously calculating the aerodynamic torque and force for each altitude and solar array paddle (SAP) attitude. Then, the optimal attitude paths were determined for each SAP angle. Finally, trade-offs will be made for the optimum switching altitude in the two deorbit phases to check the feasibility of ADR missions.

The SBAS is the standard augmentation systems which ensure the integrity of navigation by providing augmentation information via satellite broadcast. The recent standards, L5 SBAS, augments DFMC (Dual-Frequency Multi-Constellation) environment with much number of satellites contributing to better availability. For full benefit of DFMC advantages, dynamic satellite mask should be introduced because the number of satellites augmented simultaneously is limited to 92. Here the author has investigated and reports the advantage of dynamic satellite mask in the recent GNSS environment. Dynamic satellite mask must be applied to augment three or more constellations with more than 92 satellites and enables augmentation of all satellites of GPS, Galileo, BDS, GLONASS, and QZSS. Even in case of augmenting two constellations, dynamic satellite mask with update interval of 1.5 to 4 hours reduces TTFF (Time to First Fix) by roughly 8 to 25%.

The progress of technologies makes possible to design integrated display format to be more flexible. The flexible format already started to apply for the small airplane category, and expects to newly apply for the regional jet category next with the consideration of its flight deck size and of an extent of commonality with the large transport aircraft's design. EASA started to study the reduced crew operation rulemaking as eMCO (extended Minimum Crew Operation) to adapt the single pilot operation gradually. It may develop more automation and autonomous for flight deck and potentially enhance the format to be more flexible. Based on these reasons, the next generation regional jet will require the novel format which meets both (1) current two men operation and (2) provision for future single pilot operation transition. This paper proposes the novel display format design based on “measures framework” for (a) improvement of the situation awareness, workload potentially comparing with conventional design, and for (b) compatible with conventional CRM without causing a new Human Factor issue. In addition, this paper also evaluates the validity of proposed format. The result shows that it will potentially contribute to enhance aircraft design safe and flexible for the future new operation.

In recent years, numerous missions aiming for sustained access to the Moon have been conceptualized and planned. To diversify future lunar missions, exploring the use of periodic orbits in the Earth-Moon system presents an alternative to the traditional lunar orbits based on the two-body problem. This study investigates solutions for insertion into periodic orbits within the Earth-Moon system, utilizing lunar swing-by maneuvers. Additionally, the study discusses the expansion of these solutions and their effects when applying powered swing-by. The findings enable direct insertion into periodic orbits using swing-by techniques, potentially broadening the scope of lunar missions and contributing to lunar exploration strategies.

Automation and autonomy have made significant progress in aircraft operations (include drones). Automation refers to a system operating according to predefined procedures, while autonomy refers to a system's ability to self-learn and make decisions in response to circumstances. Developments in this technology have the potential to improve operational safety, efficiency and flexibility. This technical note introduces three publicly available documents from JARUS and ASTM International and summarizes the content of each. Suggestions are made to facilitate similar discussion in Japan.