Uncrewed Systems Technology 047 l Aergility ATLIS l AI focus l Clevon 1 UGV l Geospatial insight l Intergeo 2022 report l AUSA 2022 report I Infinity fuel cell l BeeX A.IKANBILIS l Propellers focus I Phoenix Wings Orca

109 Profit-centred configuration The Orca’s hybrid fixed-wing VTOL configuration combines greater speed and range than a multi-copter with the ability to take off and land almost anywhere with very little infrastructure. “This means more possible nodes in the delivery network, more jobs and more profit,” Iordache says. Its VTOL capability is provided by six lifting rotors, and forward thrust by a pair of propellers, all spun by electric motors drawing power from lithium-ion batteries. It also features a blown flap high-lift system, which contributes to the Orca’s high payload for its wingspan. Another goal of the propulsion system design is low perceived noise, which Iordache notes is heavily influenced by the pitch of the sound. “We have also conducted this kind of study in the past with our PW Manta-Ray [now retired], and the Orca’s noise optimisation will start in February 2023.” Wingspan broadly correlates with the mass of an aircraft, and relates to the risk it presents to people on the ground. Staying below that 3 m limit means the vehicle is subject to less paperwork and administrative costs, Iordache says. This was one of several design limitations that the company respected when optimising the vehicle for its application. Another was the mandatory parachute, which is a ground safety measure deployed by the flight termination system (FTS), complemented by the ability to continue flying after powertrain or actuator failure. The last of these was a stall speed of 22 m/s at MTOW, which Iordache explains is a reasonable speed that contributes to good handling and transition from hover to forward flight and back in short distances, ensuring that this happens within a legally mandated area on the ground. To optimise the payload, Phoenix Wings created a large database of common payload geometries, obtaining the measurements of logistics companies’ standard boxes, medical supplies containers, tool boxes and so on. It correlated these with their mass, including their typical contents, to ensure that the volume and mass are well-matched by the Orca’s payload capacity, which Iordache refers to as “reasonable density”. Combined with research on the required delivery ranges, this information enabled the company to judge how much of the existing market could be covered with the Orca. The size and shape of the cargo bay, and the speed and convenience of access to it, are important for a safe and fast turnaround to minimise time on the ground and to maximise productivity, Iordache adds. Considering these factors led to the upward-pivoting nose section that provides unobstructed access. In addition, battery capacity can be adjusted to allow for longer ranges with less cargo, and to provide redundancy. Optimising the capacity led to the development of a modular concept that allows the use of different battery and cargo combinations, and Iordache explains that the range quoted above is for a one-way trip including take-off and landing, accounting for extended safety margins and moderate headwinds. Optimisation tool Overall, the optimisation process involved many engineering trade-offs. To help with these decisions the Phoenix Wings team used a numeric optimisation tool for complete aircraft design and mission simulation, basically optimising for cost per delivery, Iordache explains. The tool was used for sizing the wing and tail surfaces, and for calculating lift, drag and stability, as well as for structural analysis and mass estimation. It Phoenix Wings Orca | Digest The Orca flies fast, resulting in a reasonable wing aspect ratio, and being a VTOL craft you don’t have to deal with the slow- flying scenario Uncrewed Systems Technology | December/January 2023 The Orca has a small wingspan in relation to its payload, enabled partly by the hybrid VTOL configuration that allows it to tolerate a relatively high stall speed