Abstract: This technical article discusses design and integration associated with distributed propulsion as a means of providing motive power with significantly reduced emissions and external noise for future aircraft concepts. The technical work reflects activities performed within a European Commission funded Framework 7 project entitled Distributed Propulsion and Ultra-high By-Pass Rotor Study at Aircraft Level, or, DisPURSAL. In this instance, the approach of distributed propulsion includes a Distributed Multiple-Fans Concept driven by a limited number of engine cores as well as one unique solution that integrates the fuselage with a single propulsor (dubbed Propulsive-Fuselage Concept) – both targeting entry-in-service year 2035+. Compared to a state-of-the-art, year 2000 reference aircraft, designs with tighter coupling between airframe aerodynamics and motive power system performance for medium-to-long-range operations indicated potentially a 40-45% reduction in CO2-emissions. An evolutionary, year 2035, conventional morphology gas-turbine aircraft was predicted to be –33% in CO2-emissions.

Abstract: This paper presents a conceptual electric airplane design utilizing Co-Flow Jet (CFJ) flow control. The purpose is to design an aircraft with high wing loading and a compact size so that an airplane can carry more battery and reach a longer range. The CFJ Electric Aircraft (CFJ-EA) mission is to carry 4 passengers at a cruise Mach number of 0.15 with a range of about 300nm. The CFJ-EA cruises at a very high CL of 1.3, which produces a wing loading of 182.3kg/m 2 , about 3 times higher than that of a conventional general aviation airplane. The aerodynamic efficiency including the power consumption of the CFJ pump (L/D)c is excellent with a value of 24 at a low momentum coefficient Cµ of 0.04. Takeoff and landing distances are also reasonable due to a very high maximum CL of 4.8, achieved with a high Cµ of 0.28. The wing is designed to pivot around its 1/4 chord axis so that it can achieve high angle of attack (AoA) without rotating the fuselage. A measure of merit defined as PMS=Passengers*Miles/S is introduced, where S is the wing planform area. The PMS of the present EA design is close to that of a conventional reciprocating engine general aviation airplane, and is 2.3 to 3.8 times greater than the PMS of the state of the art EA. The design results suggest that the CFJ-EA has a far greater range than a same size EA using a conventional wing design. Or for the same range, the CFJ-EA has a much smaller size than a conventional design. This design is the first trail with no systematic design optimization. The CFJ-EA concept may open the door to a new class of general aviation EA designs. The same CFJ flow control technology can also be used for other general aviation airplanes with conventional propulsion systems and for high altitude airplanes to reduce size.

Abstract: Disclosed is an unmanned aerial vehicle, comprising a fuselage (1), a shell assembly (3) and a functional component. The fuselage comprises a fuselage body (10). The shell assembly (3) is connected at a front end of the fuselage body. The functional component is mounted at a rear end of the fuselage body. An upper end face of the functional component is a first circular arc face. An upper end face of the shell assembly (3) is a second circular arc face. The first circular arc face is adjacent to the second circular arc face, and the first circular arc face and the second circular arc face constitute a streamlined curved face. Such a design can solve the problems of existing unmanned aerial vehicles having low working efficiency and consuming a large amount of energy caused by the irrational layout of the unmanned aerial vehicles.

Abstract: In one aspect the present subject matter is directed to a gas-electric propulsion system for an aircraft. The system may include a turbofan jet engine, an electric powered boundary layer ingestion fan that is coupled to a fuselage portion of the aircraft aft of the turbofan jet engine, and an electric generator that is electronically coupled to the turbofan jet engine and to the boundary layer ingestion fan. The electric generator converts rotational energy from the turbofan jet engine to electrical energy and provides at least a portion of the electrical energy to the boundary layer ingestion fan. In another aspect of the present subject matter, a method for propelling an aircraft via the gas-electric propulsion system is disclosed.

Abstract: An aircraft includes at least one propulsion engine, coupled to a fuselage, and configured to provide forward thrust to propel the aircraft along a first vector during forward flight. Each of at least two of multiple rotors coupled to the fuselage is coupled to a motor configured to supply power to that rotor and/or to draw power from that rotor. At least two of the rotors are configured to operate during forward flight to provide at least some lift to the aircraft along a second vector. A flight control system is configured to control the rotors that are configured to operate during forward flight in a power managed regime in which a net electrical power, consisting of the sum of the power being supplied to or drawn from each rotor by its motor, is maintained within a range determined by a feedback control system of the flight control system.

Abstract: A vertical take-off and landing (VTOL) aircraft is provided. The aircraft includes a wing, nacelles supportively disposed at opposite ends of the wing, proprotors respectively attached to each of the nacelles with each of the proprotors being rotatable to generate lift in vertical flight and thrust in horizontal flight and a delta-wing shaped fuselage disposed along the wing between the nacelles.

Abstract: The invention provides a foldable unmanned aerial vehicle comprising a fuselage and an information acquisition device, wherein the information acquisition device is installed on the fuselage; the unmanned aerial vehicle further comprises a first connecting piece, a second connecting piece, at least two rotor shafts, and at least three undercarriages, wherein the rotor shafts are movably connected with the fuselage through the first connecting piece; the at least three undercarriages are movably connected with the fuselage through the second connecting piece. When the unmanned aerial vehicle performs no flight work, the rotor shafts and the undercarriages can be located at a retractive state relative to the fuselage, so as to facilitate carrying by a worker during field operation, meanwhile when the unmanned aerial vehicle needs to perform flight work, the undercarriages can be in the retractive state relative to the fuselage, so that the acquisition device can fly for 360 degrees without being shielded to achieve acquisition work.

Abstract: This work investigates the aerodynamic interference among airplane components caused by rudder deflection for a typical turboprop aircraft geometry through the computational fluid dynamics technique. At no sideslip, an airplane is in symmetric flight conditions. The rudder deflection creates a local sideslip angle close to the vertical tailplane, and this effect is increased by fuselage and horizontal tail. Typical semiempirical methods, such as United States Air Force Stability and Control Data Compendium (USAF DATCOM), do not take into account for these effects, proposing the same corrective parameters both for pure sideslip and rudder deflection conditions. Numerical analyses executed on several aircraft configurations with different wing and horizontal tailplane positions show that the interference factors are smaller than those predicted by the USAF DATCOM procedure, providing guidelines for a more accurate aircraft directional control analysis and hence rudder preliminary design.

Abstract: A disclosed aircraft propulsion system includes a gas turbine engine supported within an aircraft fuselage, a main drive driven by the gas turbine engine and an open rotor propeller system supported outside of the aircraft fuselage separately from the gas turbine engine. A secondary drive that is driven by the main drive drives the open rotor propeller system.

Abstract: An aircraft is provided including a fuselage and an aft engine. The fuselage defines a top side, a bottom side, and a frustum located proximate an aft end of the aircraft. The frustum defines a top reference line extending along the frustum at a top side of the fuselage, and a bottom reference line extending along the frustum at a bottom side of the fuselage. The top and bottom reference lines meet at a reference point aft of the frustum. The fuselage further defines a recessed portion located aft of the frustum and indented inwardly from the bottom reference line. The aft engine includes a nacelle extending adjacent to the recessed portion of the fuselage such that the aft engine may be included with the aircraft without interfering with, e.g., a takeoff angle of the aircraft.

Abstract: An independent partial assessment is provided of the technical viability of the Skylon aerospace plane concept, developed by Reaction Engines Limited (REL). The objectives are to verify REL's engineering estimates of airframe aerodynamics during powered flight and to assess the impact of Synergetic Air-Breathing Rocket Engine (SABRE) plumes on the aft fuselage. Pressure lift and drag coefficients derived from simulations conducted with Euler equations for unpowered flight compare very well with those REL computed with engineering methods. The REL coefficients for powered flight are increasingly less acceptable as the freestream Mach number is increased beyond 8.5, because the engineering estimates did not account for the increasing favorable (in terms of drag and lift coefficients) effect of underexpanded rocket engine plumes on the aft fuselage. At Mach numbers greater than 8.5, the thermal environment around the aft fuselage is a known unknown−a potential design and/or performance risk issue. The adverse effects of shock waves on the aft fuselage and plumeinduced flow separation are other potential risks. The development of an operational reusable launcher from the Skylon concept necessitates the judicious use of a combination of engineering methods, advanced methods based on required physics or analytical fidelity, test data, and independent assessments.

Abstract: The negative impact of aircraft noise includes effects on population’s health, land use planning and economic issues such as building restrictions and operating restrictions for airports. Thus, the reduction of noise generated by aircraft at take-off and approach is an essential consideration in the development of new commercial aircraft. Among the different aircraft noise sources, landing gear noise is one of the most significant during approach. This research presents results from the European Clean Sky funded ALLEGRA project, which investigated a full-scale Nose Landing Gear (NLG) model featuring the belly fuselage, bay cavity and hydraulic dressing. Tests were performed for a variety of wind speeds and yaw angles. In this paper, a characterization of the noise generated by the full-scale Nose Landing Gear (NLG) model is presented and the different techniques used for characterizing acoustic sources on the NLG are described. The landing gear noise source is characterized in terms of OASPL, directivity, source spectra, PNL and PNLT. A comparison between the NLG with and without the application of low noise technology is presented.Copyright © 2015 by ASME

Abstract: An unmanned aerial vehicle 2 comprising: a fuselage 4 ; and a wing 6 comprising a central wing section 12 pivotably mounted to the fuselage 4 and a pair of outer wing sections 14 a, 14 b pivotably mounted to the central wing section 12 ; wherein the wing 6 has a folded configuration in which the central wing section 12 and the outer wing sections 14 a, 14 b are stacked on top of one another and are aligned with a longitudinal axis of the fuselage 4 ; and a deployed configuration in which the central wing section 12 is substantially perpendicular to the fuselage 4 and the outer wing sections 14 a, 14 b extend from the central wing section 12 away from the fuselage 4.

Abstract: The reduction of noise generated by aircraft at take-off and approach is crucial in the design of new commercial aircraft. Landing gear noise is significant contribution to the total noise sources during approach. The noise is generated by the interaction between the non-aerodynamic components of the landing gear and the flow, which leads to turbulence generated noise. This research presents results from the European Clean Sky funded ALLEGRA project. The project investigated a full-scale Nose Landing Gear (NLG) model featuring the belly fuselage, bay cavity and hydraulic dressing. A number of low noise treatments were applied to the NLG model including a ramp door spoiler, a wheel axel wind shield, wheel hub caps and perforated fairings. Over 250 far field sensors were deployed in a number of microphone arrays. Since technologies were tested both in isolation and in combination the additive effects of the technologies can be assessed. This study describes the different techniques used to quantify the contribution of each technology to the global noise reduction. The noise reduction technologies will be assessed as a function of frequency range and through beamforming techniques such as source deletion.Copyright © 2015 by ASME

Abstract: A five-wing aircraft transitions smoothly between vertical and horizontal flight modes, and enhances pitch neutrality of the aircraft when in flight at all speeds to improve flight efficiency. The aircraft includes a fuselage, a fixed wing assembly coupled to the fuselage and having a front fixed wing and a rear fixed wing, the front fixed wing coupled to the front portion of the fuselage and the rear fixed wing coupled to the rear portion of the fuselage, the front fixed wing and rear fixed wing being connected together by winglets, a tilt-wing pivotably mounted to the central portion of the fuselage, and a pair of rotary wings coupled to the tilt-wing. The tilt-wing pivotably adjusts to permit the aircraft to transition smoothly between vertical and horizontal flight. The rotary wings generate thrust or lift depending on the orientation of the tilt-wing.

Abstract: A mechanism for stowing and/or adjusting a ducted propeller of a flying object, the flying object comprising a fuselage and at least one pair of wings, the outer walls of which together define a shell of the flying object, comprising a ducted propeller comprising a substantially cylindrical duct, which defines a longitudinal axis of the ducted propeller and is open at the base faces thereof, a rotor comprising a plurality of rotor blades, which is set up to rotate in a plane perpendicular to the longitudinal axis of the ducted propeller, and a drive device for driving the rotor; a receiving chamber, provided in the fuselage and/or a wing of the flying object, for the ducted propeller; a mechanism which is set up to transfer the ducted propeller from a stowed state into a deployed state.

Abstract: The wake characteristics of a rotorcraft are affected by the proximity of a rotor to the ground surface, especially during hover. Ground effect is encountered when the rotor disk is within a distance of a few rotor radii above the ground surface and results in an increase in thrust for a given power relative to that same power condition with the rotor out of ground effect. Although this phenomenon has been highly documented and observed since the beginning of the helicopter age, there is still a relatively little amount of flow-field data existing to help understand its features. Joint Army and NASA testing was conducted at NASA Langley Research Center using a powered rotorcraft model in hover at various rotor heights and thrust conditions in order to contribute to the complete outwash data set. The measured data included outwash velocities and directions, rotor loads, fuselage loads, and ground pressures. The researchers observed a linear relationship between rotor height and percent download on the fuselage, peak mean outwash velocities occurring at radial stations between 1.7 and 1.8 r/R regardless of rotor height, and the measurement azimuthal dependence of the outwash profile for a model incorporating a fuselage. Comparisons to phase-locked PIV data showed similar contours but a more contracted wake boundary for the PIV data. This paper describes the test setup and presents some of the averaged results.

Abstract: The invention relates to an automatic landing system and method of a rotor aircraft. The system comprises a controller, a laser generator, a camera, an electronic speed regulator and a motor for driving a propeller of the rotor aircraft to rotate; the laser generator and the camera are located at the bottom of a fuselage of the rotor aircraft; the laser generator is provided with two emission heads; laser beams emitted by the two emission heads are axially symmetrically distributed by taking the central axis of the fuselage as the symmetrical axis; the central axis is vertical to the horizontal plane of the ground; and an included angle formed between the laser beams and the central axis is an acute angle. According to the automatic landing system and method of the rotor aircraft, the laser generator, the camera and the controller are matched, so that the flying speed and the displacement of the rotor aircraft can be controlled, and the automatic landing effect is realized.

Abstract: The invention discloses a folding type aerial photography aircraft The folding type aerial photography aircraft comprises an unmanned aircraft fuselage, wherein the unmanned aircraft fuselage is movably connected with multiple supporting arms, the supporting arms rotate around the unmanned aircraft fuselage to unfold or rotate to enter the unmanned aircraft fuselage, the supporting arms are movably connected with propeller components, the propeller components rotate to unfold or are folded above the supporting arms, the unmanned aircraft fuselage is movably connected with a pan-tilt, and a camera is arranged on the pan-tilt Through the way, the folding type aerial photography aircraft disclosed by the invention can reduce the volume of the aerial photography aircraft, saves the space, and is easy to carry

Abstract: An aircraft's two wings and joined thruster propellers or turbines serve as rotary wings in helicopter mode and as fixed wings in airplane mode. The thrusters along the wingspans or at the wing tips drive both rotary wing rotation and airplane flight. Large-angle controlled feathering about the pitch change axes of the left and right wings and thrusters allows them to rotate, relative to each other, between facing and thrusting forward in the same direction for airplane flight or facing and thrusting oppositely for helicopter flight. Optional controls include: helicopter cyclic and collective pitch; airplane roll by differential wing pitch; yaw by differential prop thrust; fuselage pitch by wing pitch change and prop thrust change interacting with an underslung craft e.g.; and fuselage yaw control independent of rotor rotation via a powered rotary mast coupling or a tail responsive to rotor downwash. A teetering rotor hub is a further option.

Abstract: The invention is related to an aircraft 1 with a fuselage 2 that accommodates at least one air breathing propulsion engine 8a, said fuselage 2 having a maximum fuselage width determined in the region of said at least one air breathing propulsion engine 8a and comprising at least one front fuselage cowling and at least one rear fuselage cowling that are each covering said at least one air breathing propulsion engine 8a at least partly, said at least one front and rear fuselage cowlings being spaced apart from each other in a direction transverse to a longitudinal axis of said at least one air breathing propulsion engine 8a by a predetermined cowling offset to define a dynamic air intake 9 through which an intake air stream is supplied to said at least one air breathing propulsion engine 8a in operation.

Abstract: This disclosure describes a configuration of an unmanned aerial vehicle (“UAV”) in which the fuselage of the UAV is center mounted and at least some of the motors are configured to encompass at least a portion of the fuselage. In such a configuration, the stator and rotor of the motor extend around a perimeter of the fuselage, the propellers are coupled to an outer perimeter of the rotor, and the propellers extend radially outward away from the fuselage. Likewise, a closed wing may be coupled to the fuselage and positioned to encompass the radially extending propellers and at least a portion of the fuselage.

Abstract: A method and apparatus for processing fuselage sections. A first fuselage section is held in a cradle system. A current shape of the first fuselage section in the cradle system is measured. Forces to change the current shape of the first fuselage section to a desired shape for connecting the first fuselage section to a second fuselage section are identified. The forces identified are applied using a system to change the current shape of the first fuselage section towards the desired shape.

Abstract: For certification, novel fuselage concepts have to prove equivalent crashworthiness standards compared to the existing metal reference design. Due to the brittle failure behaviour of CFRP this requirement can only be fulfilled by a controlled progressive crash kinematics. Experiments showed that the failure of a twin-walled fuselage panel can be controlled by a local modification of the core through-thickness compression strength. For folded cores the required change in core properties can be integrated by a modification of the fold pattern. However, the complexity of folded cores requires a virtual design methodology for tailoring the fold pattern according to all static and crash relevant requirements. In this context a foldcore micromodel simulation method is presented to identify the structural response of a twin-walled fuselage panels with folded core under crash relevant loading condition. The simulations showed that a high degree of correlation is required before simulation can replace expensive testing. In the presented studies, the necessary correlation quality could only be obtained by including imperfections of the core material in the micromodel simulation approach.