Vertical take-off and landing (VTOL) tilt-wing passenger aircraft

Abstract

Disclosed herein is a VTOL tilt-wing aircraft that serves as a 4-6 passenger airliner for scheduled service between city centers and that is optimized for travel distances from 100-500 miles fully loaded with passengers and fuel. The VTOL aircraft solves technical, cost, and time problems inherent in other forms of transportation, including, but not limited to, rail, passenger airlines, and helicopters. The VTOL aircraft (1) takes off and lands like a helicopter, (2) flies fast like a jet, and (3) costs less than or comparable to a helicopter.

Claims

1. A vertical take-off and landing (VTOL) tilt-wing aircraft comprising: a fuselage made of carbon fiber, aluminum, or both, the fuselage further comprising: a front section with cockpit; a middle section passenger cabin, the passenger cabin having a fire-resistant cabin interior; a tail section containing an engine and a fuel tank; and seating for up to 6 occupants; a horizontally mounted stabilizing propeller connected at a center of an end of the tail section; two horizontal stabilizers connected to the tail section on opposite sides of the horizontally mounted stabilizing propeller; two vertical stabilizers connected one to each horizontal stabilizer; a single wing rotatably coupled to the fuselage, the single wing having a tapered leading edge and a tapered trailing edge, the single wing notched in the center so that the single wing can rotate about an attachment at a top of the fuselage and trailing portions of the single wing on each side of the notch pass to either side of the middle section passenger cabin as the single wing tilts from 0 degree of wing angle to a maximum of 120 degrees of wing angle, wherein the attachment between the single wing and the fuselage comprises two trapeze mounts affixed on either side of the top of the fuselage, wherein each trapeze mount includes a circular hole with bearing affixed within, and wherein a circular tube inserted into the bearing is joined to the single wing such that as the circular tube rotates within the trapeze bearings, the single wing member rotates and alters the wing angle; a slew-ring worm drive controlling rotation of the circular tube, the slew-ring worm drive comprising a circular worm-wheel gear encircling the circular tube, the worm-wheel gear engaged to a zero-backlash worm gear, the worm gear placed on a shaft driven by dual-redundant coaxial electric motors; two wing propellers connected one to each end of the wing, each mechanically coupled along a drive path to the engine, wherein an input shaft from the engine is attached to a T gearbox centrally located in the single wing, and two wing shafts at opposite 90-degree angles to the input shaft attach the T gearbox to two L gearboxes, one L gearbox in each side of the single wing, and each L gearbox has an output shaft rotated 90 degrees from the connected wing shaft; landing skids or footpads which extend from the fuselage for takeoff and landing and retract flush with the fuselage during flight; wherein the wing propeller plane or rotation is approximately horizontal when in helicopter mode for takeoff and landing, and approximately vertical when in airplane mode during flight; and wherein the VTOL tilt-wing aircraft has a maximum takeoff weight of 6990 pounds, a cruise speed of at least 350 knots, and a maximum range of at least 500 miles.

2. The aircraft of claim 1, further comprising the passenger cabin having a split cabin door and an emergency door opposite the split cabin door.

3. The aircraft of claim 1, wherein each output shaft connects to a double universal joint which is connected to a second shaft riding within an elastomer lined circular bearing and connected to one of the wing propellers.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings, closely related figures and items have the same number but different alphabetic suffixes. Processes, states, statuses, and databases are named for their respective functions.

(2) FIG. 1 shows the aircraft in helicopter mode, gear down, left front top perspective.

(3) FIG. 2 shows the aircraft in helicopter mode, gear down, left front bottom perspective.

(4) FIG. 3 shows the aircraft in helicopter mode, gear down, front (nose of aircraft).

(5) FIG. 4 shows the aircraft in helicopter mode, gear down, back (tail).

(6) FIG. 5 shows the aircraft in helicopter mode, gear down, right.

(7) FIG. 6 shows the aircraft in helicopter mode, gear down, left (door side).

(8) FIG. 7 shows the aircraft in helicopter mode, gear down, top.

(9) FIG. 8 shows the aircraft in helicopter mode, gear down, bottom.

(10) FIG. 9 shows the aircraft in helicopter mode, gear up, left front top perspective.

(11) FIG. 10 shows the aircraft in helicopter mode, gear up, left front bottom perspective.

(12) FIG. 11 shows the aircraft in helicopter mode, gear up, front (nose of aircraft).

(13) FIG. 12 shows the aircraft in helicopter mode, gear up, back (tail).

(14) FIG. 13 shows the aircraft in helicopter mode, gear up, right.

(15) FIG. 14 shows the aircraft in helicopter mode, gear up, left (door side).

(16) FIG. 15 shows the aircraft in helicopter mode, gear up, top.

(17) FIG. 16 shows the aircraft in helicopter mode, gear up, bottom.

(18) FIG. 17 shows the aircraft in airplane mode, gear up, left front top perspective.

(19) FIG. 18 shows the aircraft in airplane mode, gear up, left front bottom perspective.

(20) FIG. 19 shows the aircraft in airplane mode, gear up, front (nose of aircraft).

(21) FIG. 20 shows the aircraft in airplane mode, gear up, back (tail).

(22) FIG. 21 shows the aircraft in airplane mode, gear up, right.

(23) FIG. 22 shows the aircraft in airplane mode, gear up, left (door side).

(24) FIG. 23 shows the aircraft in airplane mode, gear up, top.

(25) FIG. 24 shows the aircraft in airplane mode, gear up, bottom.

(26) FIG. 25 shows the fuselage general layout, top view.

(27) FIG. 26 shows the fuselage general layout, perspective view.

(28) FIG. 27 shows the tilt-wing, perspective view.

(29) FIG. 28 shows the tilt-wing, close-up perspective view.

(30) FIG. 29 shows the tilt-wing gear mechanism, perspective view.

(31) FIG. 30 shows the tilt-wing gear mechanism, left top view of the tilt-wing gear mechanism.

(32) FIG. 31 shows the tilt-wing gear mechanism, front top view of the tilt-wing gear mechanism.

(33) FIG. 32 is a diagram of the fly-by-wire system components.

(34) FIG. 33 is a diagram of the software architecture design.

(35) FIG. 34 is a diagram of the networked integrated flight control electronics (N-IFCE) components.

(36) FIG. 35 is a perspective drawing of the emergency exit as viewed from the port rear passenger seat.

(37) FIG. 36 is a perspective view of the interior showing the optionally installable sixth seat.

(38) FIG. 37 is a cutaway drawing of the elastomeric main propeller drive shaft bearing and universal joint interface to the output of the L gearbox.

DETAILED DESCRIPTION, INCLUDING THE PREFERRED EMBODIMENT

(39) In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which are shown, by way of illustration, specific embodiments which may be practiced. It is to be understood that other embodiments may be used, and structural changes may be made without departing from the scope of the present disclosure.

Terminology

(40) The terminology and definitions of the prior art are not necessarily consistent with the terminology and definitions of the current disclosure. Where there is a conflict, the following definitions apply.

(41) CTOL aircraft—Conventional take-off and landing aircraft (www.wikipedia.org/wiki/CTOL).

(42) eVTOL aircraft—Electric VTOL aircraft.

(43) FIKI—Flight into known icing.

(44) Inside-the-city—SEE within-city.

(45) IoT—Internet of Things (www.wikipedia.org/wiki/Internet_of_things).

(46) PAC—Personal aircraft, a single-person aircraft.

(47) PAV—Personal air vehicle (www.wikipedia.org/wiki/Personal_air_vehicle).

(48) Proprotor (AKA “prop-roter”)—A spinning airfoil that is used as both an airplane-style propeller and a helicopter-style rotor (www.wikipedia.org/wiki/Proprotor).

(49) QTR aircraft—Quad tiltrotor aircraft, i.e. an aircraft using four tiltrotors.

(50) Tiltrotor aircraft (AKA “tilt-rotor aircraft”)—A tiltrotor aircraft generates lift and propulsion by way of one or more powered rotors mounted on rotating engine pods or nacelles usually at the ends of a fixed wing or an engine mounted in the fuselage with drive shafts transferring power to rotor assemblies mounted on the wingtips. It combines the vertical lift capability of a helicopter with the speed and range of a conventional fixed-wing aircraft. For vertical flight, the rotors are angled so the plane of rotation is horizontal, lifting the way a helicopter rotor does. As the aircraft gains speed, the rotors are progressively tilted forward, with the plane of rotation eventually becoming vertical. In this mode the wing provides the lift, and the rotor provides thrust as a propeller. Since the rotors can be configured to be more efficient for propulsion and it avoids a helicopter's issues of retreating blade stall, the tiltrotor can achieve higher speeds than helicopters (www.wikipedia.org/wiki/Tiltrotor).

(51) Tiltwing aircraft (AKA “tilt-wing aircraft”)—A tiltwing aircraft features a wing that is horizontal for conventional forward flight and rotates up for vertical takeoff and landing. It is similar to the tiltrotor design where only the propeller and engine rotate (www.wikipedia.org/wiki/Tiltwing).

(52) Transcend Vy 400—The VTOL disclosed in this patent document.

(53) TRL—Technology readiness level (www.wikipedia.org/wiki/Technology_readiness_level).

(54) TVF—Transformative Vertical Flight. Since 2014, AHS International has been leading a series of workshops with NASA, AIAA, and SAE on Transformative Vertical Flight (TVF), and built a community of aerospace professionals that includes technical, regulatory, and business elements, and exploring the potential for new forms of air transportation systems with innovative propulsion systems. The focus has been on systems that embody combinations of on-demand, electric and hybrid-electric propulsion, and vertiport-capable configurations and designs (www.vtol.org/what-we-do/transformative-vtol-initiative).

(55) V/STOL—A vertical and/or short take-off and landing (V/STOL) aircraft. VTOL aircraft are a subset of V/STOL aircraft that do not require a runway (www.wikipedia.org/wiki/V/STOL).

(56) VTOL aircraft—Vertical take-off and landing (VTOL) aircraft (www.wikipedia.org/wikiNTOL).

(57) Within-city—Intra-city, as opposed to inter-city or city-to-city.

Operation

(58) Referring to FIGS. 1-25, the Vy 400 is a single hull VTOL tilt-wing passenger aircraft 100 having a maximum takeoff weight of 6990 pounds, cruise speed of 350 knots, and a maximum range of 500 miles. The Vy 400 VTOL tilt-wing aircraft has a fuselage 2500, the fuselage having a front section 2510 with a cockpit for an optional pilot occupant, a middle section 2520 having a cabin for multiple passenger occupants, and a rear section 2530 for the engine and fuel tank. A single wing member 110 is rotatably coupled to the fuselage, each end of the wing having a propeller 120 disposed at a fixed position on the outer edge of the wing, each propeller mechanically coupled along a drive path to the single engine, which is deposed on the rear section of the fuselage. The rear (or tail) section of the fuselage includes a horizontally-mounted stabilizing propeller 130 at the center of the tail section, two horizontal stabilizers 140 connected to the tail section, connected to two vertical stabilizers 145. Helicopter-style skids or footpads 150 extend from the hull for takeoff and landing and retract flush with the hull during flight.

(59) Like all VTOL aircraft, the Vy 400 flies like a helicopter (helicopter mode) when the wings are rotatably angled so that the plane of rotation is approximately horizontal 1500, the precise angle selected dynamically to achieve desired flight behavior with regard to flight path angle, rate of climb, station keeping et al., and the Vy 400 flies like a jet (airplane mode) when the wings are rotatably angled so that the plane of rotation is approximately vertical 1900, the precise angle selected dynamically to achieve desired flight behavior with regard to flight deck angle, rate of climb, true air speed, et al.

(60) This Vy 400 has been designed with a single market as its only application, namely a 6-seat thin haul commuter airline. This has resulted in many design tradeoffs: range has been traded for speed, accommodations have been traded off for inexpensive operation, and the aircraft is designed with the goal of a low unit cost. With a price of $3.5 million, the Vy 400 costs significantly less than the projected $25 million price for the AgustaWestland AW609 (AKA Leonardo 609), the closest comparable aircraft. The price per seat is $583,333 for the Vy 400, $2.8 million for the Leonardo 609, and $400,000-$840,000 for a typical commercial airliner. A price-optimized autonomous Vy 400 delivers a price per seat of only $400,000.

(61) The major components of the aircraft, arranged approximately by decreasing cost, are as follows:

(62) Powerplant.

(63) The Vy 400 is powered by a single Pratt & Whitney Canada PT6 (P&WC) PTEA engine, one of the most reliable engines ever built. The engine is connected via a drivetrain to two propellers, one on each wing, and the horizontally-mounted tail propeller.

(64) Fly-by-Wire and Flight Control.

(65) The first fly-by-wire commercial aircraft was the Airbus A320 in 1988 with a unit cost of $99 million. Since then the price and time between major development milestones have fallen exponentially so that the latest fly-by-wire aircraft, the 2014 Embraer Legacy 450, has a unit cost of $17 million. The complexity of general aviation fly-by-wire systems has also decreased since the first systems in the Dassault Falcon in 2007 and the Gulfstream 650 in 2008.

(66) Referring now to FIG. 32, fly-by-wire system components. Primarily, the Vy 400 fly-by-wire system 3200 performs the following essential functions typical of a fly-by-wire flight control system:

(67) 1. Converts pilot 3210 or autopilot 3220 input into movements of the control surfaces, engine power, and parachute.

(68) 2. Ensures the aircraft is stable in all flight regimes.

(69) 3. Enforces control laws that ensure that the aircraft flies within architectural limits.

(70) Secondarily, the fly-by-wire system automates the transition process from vertical (helicopter mode) to horizontal (airplane mode) flight and back. Any additional flight automation (including, but not limited to, automating takeoff and landing, station holding, and waypoint tracking) is performed by an autopilot system.

(71) Referring now to FIG. 33, software architecture design. Regarding flight control generally, a deterministic network 3300 of Distributed Flight and Actuator Controllers (DFACs) implements Integrated Flight Control Electronics (IFCE) functionality.

(72) Referring now to FIG. 34, N-IFCE, in some embodiments, DFACs 3400 combine Flight Control System (FCS) and Remote Electronics Unit (REU) capabilities, while in other embodiments, FCS and REU functions are implemented by separate units. All units are interconnected via a dual-redundant bus architecture, and the resulting Networked IFCE (N-IFCE) 3300 is less expensive, higher performance, and more flexible, while achieving critical systems engineering safety guarantees.

(73) More specifically, the FCS software includes a system of software modules devised so that certain modules implement “lower-level” or “lower-layer” functionality and certain other modules implement “higher-level” or “higher-layer” functionality, along with certain relationships implemented in a control and communications scheme among the modules.

(74) It is typically the case that lower-level modules perform less complex computations under stricter time and reliability constraints, while higher level modules may perform more complex computations with looser time and reliability constraints. It is a key attribute of the FCS that necessary safety and performance guarantees are always met, while still enabling higher-level computations to be completed on a best-effort basis.

(75) The FCS system may be implemented on one or more physical computing devices. The software code loaded onto each computing device is capable of performing all of the same functions as the code loaded onto any computing device, though the code may differ necessarily to accommodate different compute device attributes (e.g. hardware architecture) or because it was derived from differing source code in order to avoid “common-mode failures.” The code on each device is self-configuring, adapting itself to its specific role based on the overall architecture of the aircraft and the functionality required by the particular computing device it is loaded onto.

(76) The code running on all of the computing devices shares information as required to compute the desired behavior of the aircraft, using one or more proven deterministic control system techniques. Generally, a decisioning scheme compares the computations and decides what actions to take. Computations that fall outside an expected normal variability range cause the software that performed it to be excluded from further participation in the control system, and a warning is logged within the FCS.

(77) Beyond a pre-defined trigger point that may or may not differ by warning type, the FCS signals a caution or warning to the aircraft's pilot, or activates the aircraft parachute, or both.

(78) The lowest level FCS code may be implemented as “firmware” in a field-programmable gate array (FPGA) or other special-purpose memory device, or in any other way that enables the required timing and safety requirements to be met. Higher-level code is implemented as one or more computing processes on a single, or group of cooperating computing devices, any of which may be physically co-located on a single computer board, or distributed throughout the aircraft and connected via a bus or network with appropriate characteristics.

(79) The FCS software interfaces with software running on third-party systems and equipment, including but not limited to sensors, autopilots, radios, actuators, motor control modules, cameras, batteries, and displays.

(80) The highest level FCS software implements the role of captain of the aircraft during unpiloted operation. The captain software validates and accepts missions; monitors aircraft systems; directs lower-level FCS software via simulated control inputs for power, propeller blade pitch, wing angle, rudder motion, elevator motion, flaperon motion, gear position, pressurization, cabin temperature, and parachute deployment; communicates with air traffic control (ATC); computes deviations from flight plans and implements them; acts on conflict resolution advisories from other aircraft systems; and performs other tasks required for the safe and efficient piloting of the aircraft.

(81) A particularly valuable feature of the FCS is its capability to perform a fully automated preflight check of all aircraft systems. The nominal values derived during certification, as embodied in the Vy 400's Pilot Operating Handbook and applicable maintenance manuals, are programmed into routines in the FCS that make use of the various sensors and other feedback mechanisms available to the FCS to ascertain that all values are within nominal ranges prior to accepting takeoff command inputs from the pilot. This enhances operating safety while at the same time reduces the time required for preflight checks, which increases the operating efficiency of the Vy 400 in airline use.

(82) The programming of the FCS with regard to the handling of fault conditions makes use of techniques proven by NASA for the Space Shuttle and other spacecraft, as well as by state of the art implementations on other fly-by-wire jet aircraft, such as the Embraer Legacy 450 and the Gulfstream G650. Such techniques generally involve, but are not limited to, the use of predetermined fault-trees, which are logical structures that direct and constrain actions in accord with detected fault conditions, current aircraft flight parameters, and other system inputs. Unlike the example aircraft above, an advantage of the Vy 400 design is that the FCS is not programmed in highly complex ways to make use of multiple redundant systems in order to enable the aircraft to land while protecting the occupants. Instead, the Vy 400 makes use of its whole-airframe parachute to protect occupants, greatly simplifying the required fault-handling logic, and the programming, testing, certification, and maintenance of the same over time.

(83) The FCS is also programmed to perform aircraft missions while protecting occupants from attempts to mis-fly the aircraft. The mission protection functionality makes use of commercially available terrain and obstacle databases such as those mandated by ICAO (www.skybrary.aero/index.php/Electronic_Terrain_and_Obstacle_Data_(eTOD)), and the ever more finely grained ones developed to facilitate drone-based services (www.airmap.com/platform/), along with fused real-time sensor data, to ensure that the aircraft cannot be flown into terrain or obstacles such as trees, buildings, boats, etc. In the most common case, attempts to mis-fly the aircraft are ignored when they do not accord with the pre-programmed flight plan. Should an aircraft occupant, including the pilot, manage in some way to induce a flight action that results in a projected impact, the aircraft maneuvers to avoid or minimize the impact energy, making use of the parachute and reorientation of the aircraft's attitude.

(84) Propellers.

(85) As VTOL aircraft gain speed and travel through the transition corridor (i.e. to/from vertical/horizontal flight), there are significant loading issues on both the propellers and gearbox. The Vy 400 uses propeller blades designed by FlexSys (www.flxsys.com/rotocraft). The FlexSys adaptive blades morph during operation, thereby reducing overall stress on the blades and gearbox (www-personal.umich.edu/-adriaens/Site/UM_CleanTech_files/Kota.pdf). With VTOL aircraft, there are design trade-offs between speed and hover efficiency of the propellers that are based on propeller disk size, chord, and twist. By employing blade-morphing technology, the Vy 400 changes the twist and the disk size, as required, during each rotation, without the complexity that is inhering in a helicopter hub.

(86) In one embodiment, the main propellers have three blades, a disc diameter of fifteen feet, and a maximum tip speed of 855 feet per second (fps). In another embodiment, there are four blades with a maximum tip speed of 660 fps.

(87) In one embodiment, the tailfan propeller has two blades, a disc diameter of three feet, a blade profile with no twist, and a tip speed of 855 feet per second (fps). In another embodiment, there are twelve blades with a maximum tip speed of 600 fps.

(88) Avionics.

(89) In addition to FCS avionics (discussed above), the Vy 400 includes industry-standard avionics systems including aircraft management, collision-avoidance, communications, flight recorders, monitoring, navigation, and weather.

(90) The Vy can optionally be equipped with a standard AR (Augmented Reality) headset for each occupant, such as the Google Glass Enterprise Edition, and others in production and under development (www.aniwaa.com/best-of/vr-ar/best-augmented-reality-smartglasses/). These headsets receive data streamed from the avionics, including flight parameters such as speed, altitude and outside air temperature; journey information, such as moving map GPS displays of the aircraft's position and its ETA; video from external aircraft cameras; et al. Occupants may choose to view a 360° video feed synthesized from a minimum of four external consumer-grade cameras such as the GoPro Fusion (gopro.com/fusion) that have been arranged in such a way that the aircraft structure can be made to disappear from view, allowing the wearer to experience the flight as if they were in an invisible aircraft. This has practical use for the pilot, enabling significantly enhanced situational awareness, particularly during high workload, close quarters takeoff and landing maneuvers. It also has entertainment use for passengers, increasing the perceived value of their flight experience.

(91) Fuel-System.

(92) The Vy 400 has a single centralized primary fuel tank in the rear section of the fuselage, thereby reducing both complexity and cost. The primary fuel tank is crash resistant, and a secondary fuel tank gravity feeds to the engine.

(93) Cabin.

(94) The cabin has metamaterial-based sound dampening; a split cabin door 155 that enables occupants to open just the top of the door, so that in case of ditching in water the fuselage is more likely to avoid flooding; referring also to FIG. 35, an emergency door 3000 on opposite side of the cabin from the main door located high enough so that in case of ditching in water the fuselage is more likely to avoid flooding; and a fire-resistant cabin interior. Referring also to FIG. 26, in addition the passenger cabin features a seat 2600 that may be rotated 180 degrees for forward-facing or rear-facing configurations; and referring to FIG. 36, an optionally installable sixth seat 3100 so that the aircraft can accommodate 1-6 occupants.

(95) Fuselage.

(96) The Vy 400 can be manufactured with carbon fiber, aluminum, or both.

(97) The Vy 400 has a frangible hull with energy absorbing seats and restraints.

(98) Drivetrain.

(99) The Vy 400 uses a simplified mechanical drivetrain where, referring also to FIG. 25, the shaft 2540 from the PTEA engine is attached to a T gearbox that is centrally located in the wing. Also referring to FIG. 29, the T gearbox 2930 has as its output two driveshafts, each at an opposite 90 degree angle to the input shaft, one to power each propeller, and also reduces the rotation speed of the input shaft by one half. Referring also to FIG. 27, each propeller is served by an identical L gearbox 2710, with input from the wing shaft on its side, and output rotated 90 degrees. Referring also to FIG. 37, the output shaft from each L gearbox 3700 connects to a universal joint 3710, which itself is connected to a second shaft 3720 that rides within a circular bearing 3730 that is lined with an elastomer 3740 that enables the propeller to dissipate aerodynamic loads via compression of the elastomer.

(100) Electrical.

(101) The Vy 400 uses doubly redundant data and power busses for all electronics on aircraft. In some embodiments, these are based on based on time-division multiple access (TDMA) over Ethernet.

(102) The Vy 400 uses dual redundant high power busses for the actuators, gear, and tilt mechanism.

(103) The Vy 400 has secure datalinks that are separated from passenger entertainment systems.

(104) Wings.

(105) Referring also to FIG. 27 through FIG. 31, tilt-wing and tilt-wing gear mechanism.

(106) The wing tilt mechanism makes the Vy 400 a tilt-wing, as opposed to tiltrotor, aircraft. The mechanism is space saving, reducing impingement of space on the main cabin. The mechanism employs an optimum design that doesn't generate damaging transient loads on failure.

(107) A single wing with a tapered leading edge, tapered trailing edge, and anhedral chosen to position the propellers at the center of gravity in helicopter mode. The wing is notched in the center in such a way that it can rotate about an attachment at the top of the fuselage and the trailing portions of the wing on each side pass to either side of the cabin as the wing tilts from 0° of wing angle to its maximum of 120° of wing angle. The wing is strengthened by a box spar at the leading edge.

(108) The wing is attached to the two trapeze mounts affixed on either side of the top of the fuselage. Each trapeze mount 2900 consists of a load-bearing structure that is roughly triangular with a rounded top. Near the top of each trapeze there is a circular hole, into which is affixed a bearing. Inserted into the bearings in both trapezes is a circular tube 2800 that is itself joined to the wing at multiple points such that, as the tube rotates within the trapeze bearings, the entire wing rotates and thereby effects its tilting.

(109) The mechanism that causes the rotation employs a slew-ring worm drive that consists of a circular worm-wheel gear 2910 of slightly larger diameter than the wing tube that is attached to the port trapeze mount, encircling the wing tube. The worm wheel is thus attached to the fuselage at the trapeze. Engaging the worm-wheel is a zero-backlash worm gear. The worm gear is placed on a shaft that is driven by dual-redundant coaxial electric motors 2920. The motors and drive shaft are attached to the structure of the trailing section of the center portion of the wing in such a way that, as the motors drive the worm-gear in one direction, it engages the worm-wheel and drives around it, increasing the tilt angle of the wing. If driven in the other direction, the worm gear drives around the worm-wheel in the other direction, thereby decreasing the tilt angle of the wing. The zero-backlash nature of the worm-gear ensures there are no uncommanded changes in wing angle when the electric motor(s) are started or stopped.

(110) The Vy 400 achieves vertical flight control with standard flight control surfaces on the main wing and variable pitch propellers. The Vy 400 does not use helicopter-style cyclics, thereby reducing both complexity and cost.

(111) Non-Wheeled Landing Gear.

(112) The Vy 400 uses retractable landing gear. In some embodiments, it consists of gear legs with a non-slip footpad 150, two in the rear, one in the front. In other embodiments, it consists of helicopter-style skids that are skinned, which helps direct airflow when close to the ground in order to enhance low-level controllability. Having no wheels reduces weight and complexity.

(113) Anti-Ice.

(114) The Vy 400 uses electric anti-icing for flight into known icing (FIKI), thereby eliminating the need for an additional fluid management system for de-icing/anti-icing fluid.

(115) Pressurization.

(116) The Vy 400 uses a simple pressurization system capable of maintaining a cabin altitude of no more than 8,000 feet MSL at altitudes up to 20,000 feet MSL. The aircraft hull is designed to appropriately distribute the load from this internal pressure via a system of passive structures embedded in the skin and other members. Gaskets are used around all penetrations of the pressure vessel to minimize air leakage and quiet any noise therefrom.

(117) Parachute.

(118) The Vy 400 employs a BRS Aerospace (brsaerospace.com) whole-airframe parachute to ensure occupant safety and minimize risk to persons and property on the ground in the event the aircraft departs controlled flight for any reason. The parachute system can be activated by a command from the pilot given via the control panel; via the FCS itself when certain critical fault conditions are detected; and by any occupant of the aircraft via pulling a manual trigger handle. The use of the BRS parachute in the Vy 400 design also reduces certification requirements and therefore the cost, risk, and time to complete certification, thereby improving the value of the entire program for all stakeholders.

Other Embodiments

(119) In another embodiment, the turbine engine, fuel tank, and mechanical drive train from engine to the propeller L-gearboxes are replaced by an electric drivetrain, namely an appropriate set of electric energy storage devices, electrical wires, and nacelle-mounted electric motors capable of providing similar power and torque to the propellers while providing similar flight range and operating costs.

(120) As will also be apparent to those skilled in the art, FCS software encompasses alternate embodiments of the software program in which the functions of the system are performed by modules different than those shown in the figures and described above. The FCS software may operate in a serial or parallel fashion, or a combination of the two, without departing from the spirit or scope of the disclosure. The FCS software program may be written in one of several widely available programming languages, and the modules may be coded as subroutines, subsystems, or objects depending on the language chosen.

(121) Furthermore, alternate embodiments that implement the FCS software in hardware, firmware, or a combination of both hardware and software, as well as distributing the modules in a different fashion will be apparent to those skilled in the art and are also within the scope of the disclosure.

(122) It is to be understood that the above description is intended to be illustrative, and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.