Final Report - 18TTD009 Group Design Project Department of Aeronautical and Automotive Engineering, Loughborough University, Leicestershire LE11 3T U, UK Project SkyRide – S270 DESIGN TEAM Harry Hay Group Leader and Propulsion Design Darshan Balasingam Ryan Beecroft Georgia Gregory Batteries and Systems Design Design and Modelling Risk and Reliability Ewa Mikinka Erandika Mohanathasan Simran Panesar Structural Design Business and Sales Stability and Systems Vandan Patel George Smith Edmund Tong Parachute and Landing Gear Aerodynamics Design Aircraft Performance Design i Executive Summary In this report, Project SkyRide design a 5 seat general aviation aircraft named the S270 (the SkyRide 270kW engine aircraft). The aim of the S270 is to increase regional mobility and reduce congestion of roads in the US by providing a low cost, fast alternative for commuters that frequently travel by car or public transport. This aircraft will make use of the existing infrastructure of small airports in the US, the majority of which are currently underutilised. This S270 follows the thin haul transport model (THT), serving as a scheduled service or on-demand “Air-Taxi”. The aircraft will carry out a standard 135 nmi mission in 45 minutes, with the capability of performing an extended sizing mission of 250 nmi in 2 hours. This is a significant time saving when compared to the equivalent car, train or bus journey. The cost of this standard 45-minute flight will be approximately $45 per person, which gives a total profit of 15%. In order to outperform and outsell competitors, the S270 aircraft will incorporate a number of advanced technologies to reduce operating costs and environmental impact. The most important of which is a series-parallel hybrid powertrain, which consists of a Siemens SP260D electric motor, a dual planetary gearset power split device and a 6 cylinder, horizontally opposed, avgas burning internal combustion engine (ICE). Lithium sulphur batteries, with an energy density of 520 Wh/kg, will be used to power the electric motor. The wing structure consists of a single spar and reinforced composite skin; this skin reduces the required number of structural ribs to 2 per wing, and thus reduces weight of the aircraft. A parachute system is installed in the aircraft which adds redundancy in the case of a loss of power or control and can be activated by passengers if the pilot were to become incapacitated. The S270 is a more electric aircraft (MEA), with increased electrification across all systems. Hydrostatic actuation across many control surfaces is an MEA concept that has improved the performance of the S270 by reducing mass and improving reliability, completely removing the requirement for hydraulics onboard the aircraft. A fly-by-light system is another innovation incorporated into the design and is shown to be ten times lighter than the equivalent fly-by-wire system. The entry to service date of the S270 is 2025 therefore all technologies incorporated in the design have a technology readiness level (TRL) of 7+. However, the design of the aircraft will allow for technologies to be continually upgraded throughout its operational lifetime, which will keep Project SkyRide ahead of competitors by continually reducing operating costs and environmental impact. The S270 uses a V-tail configuration to reduce mass of the aircraft. The ruddervators control pitch and yaw which can often lead to control issues, however the S270 has been found to be stable in lateral and longitudinal directions, and hence the need for stability augmentation is mitigated. ii Cost analysis has shown a 43% reduction in operating costs and a 37% reduction in unit costs compared to competitor aircraft. Cost of production will be further reduced as production of the S270 expands to a larger scale. Public perception of the S270 will be vital to its success, therefore the propeller and powertrain have been designed to minimise noise which will significantly reduce disturbances to people living near the small regional airports. In addition, taxi, take-off and climb phases are all powered by mostly electric propulsion with minimal contribution from the ICE, which reduces noise in these close-to- ground phases of the mission. Part 1 of this report outlines a brief technical description of the aircraft. Part 2 outlines a detailed design of all aspects of the aircraft, including propulsion, structures, onboard systems, aerodynamics, and stability and control. Detailed cost and risk analysis are also conducted to assess the viability of the overall project. Finally, Part 3 shows the public engagement activities carried out by the Project SkyRide team. This main aim of this public engagement was to increases the public’s awareness of environmental issues associated with air travel and show people how Project SkyRide is tackling these issues. iii Contents DESIGN TEAM .................................................................................................................................. i Executive Summary ........................................................................................................................... ii Nomenclature .................................................................................................................................... ix Part 1. Technical Description ..................................................................................................... 1-1 1.1. Introduction ..................................................................................................................... 1-1 1.2. Requirements ................................................................................................................... 1-1 1.3. Market Research .............................................................................................................. 1-2 1.4. Key Parameters ............................................................................................................... 1-3 1.5. S270 3D Renders and General Arrangement Drawing ................................................... 1-5 1.6. Aerodynamics Summary ................................................................................................. 1-7 1.6.1. Aerofoil ................................................................................................................... 1-7 1.6.2. Wing Planform ........................................................................................................ 1-7 1.6.3. Drag Breakdown ..................................................................................................... 1-8 1.7. Propulsion Summary ....................................................................................................... 1-9 1.7.1. Powertrain Design ................................................................................................... 1-9 1.8. Mass Breakdown ............................................................................................................. 1-9 1.9. Batteries Summary ........................................................................................................ 1-12 1.10. Parachute Design ....................................................................................................... 1-13 1.11. Stability and Control Summary ................................................................................. 1-14 1.12. Structures Summary .................................................................................................. 1-15 1.13. Systems Summary ..................................................................................................... 1-16 1.14. Risk and Reliability ................................................................................................... 1-18 1.14.1. Certification ........................................................................................................... 1-18 1.15. Cost Analysis............................................................................................................. 1-18 1.16. Business Case Summary ........................................................................................... 1-19 1.17. Evaluation and Feasibility ......................................................................................... 1-20 Part 2. Supporting Information ................................................................................................... 2-1 2.1. Design Problem and Requirements ................................................................................. 2-1 iv 2.1.1. Air Taxi Business .................................................................................................... 2-1 2.2. Design Evolution ............................................................................................................. 2-2 2.2.1. Initial Concepts ....................................................................................................... 2-2 2.2.2. Down Selection Matrix ........................................................................................... 2-2 2.2.3. Concept Selection .................................................................................................... 2-5 2.2.4. Design Changes ....................................................................................................... 2-5 2.2.5. Final Concept .......................................................................................................... 2-5 2.3. Aerodynamics ................................................................................................................