Showing papers on "Landing gear published in 1994"

Multi-purpose aircraft

Abstract: Several innovative systems for an aircraft, and aircraft incorporating them, are disclosed. Features include inboard-mounted engine(s) (24, 25) with a belt drive system (84, 99) for turning wing-situated propellers (8, 9); compound landing gear integrating ski (29, 114), pontoon and wheel (18, 19, 21) subcomponents; pivotal mounting armatures (6, 7) for landing gear and/or propellers which provide a plurality of possible landing gear and/or propeller configurations; and a compound wing structure (14, 15) featuring extendable wing panels (4, 5) that permit the wing span of the aircraft to be nearly doubled while in flight. Aircraft incorporating such features will enjoy several safety advantages over conventional multi-engine aircraft and will be capable of modifications during flight which permit landings on any of snow, hard surfaces (runways) and water.

Ground state-fly state transition control for unique-trim aircraft flight control system

Abstract: An aircraft control system for an unique-trim, model-following system includes a feedforward shaping function that provides quickening of pilot input, and an automatic trim function that accommodates return of the cockpit controller to an unique, centered position during trimmed flight. The basic control law is reconfigured in response to the changing state of landing gear contact to support transitions between ground state and fly state conditions. The state of the landing gear is monitored continually to recognize the occurrence of initial ground contact and whether the aircraft is constrained about a rotational axis due to ground contact. The control is altered progressively as the transition proceeds so that command of the control surface is consistent with the degree of constraint imposed by ground contact.

Aircraft steering system and method for large aircraft having main landing gear steering during low taxi speed while nose gear is castored

Abstract: A steering method and system for large aircraft wherein during low speed taxi the main landing gear wheels are steered and the nose gear is free to castor. During high speed taxi such as during take off and landing, the main gear steering is locked out while the nose gear is steered.

Fighter aircraft having low aerodynamic drag and low radar signature configuration

Abstract: A fighter aircraft achieves low aerodynamic drag and radar signature without sacrificing flight performance through a unique arrangement of the main weapons bay, the auxiliary weapons bays, and the main landing gear. Separate main and auxiliary weapons bays permit a narrower fuselage than could be obtained with a single common bay. Also, the auxiliary weapons bays and the landing gear can be aligned outboard of the main weapons bay without needing to increase the length or width of the aircraft. The air intake ducts extend aft from the intake and curve upwardly and inwardly over the main weapons bay. The result of the design configuration is an aircraft which has a forward aspect reduced to the minimum necessary to accommodate the components that need forward visibilities, which translates to minimum aerodynamic drag and radar signature.

Model aircraft constructed with extruded fluted plastic sheet

Abstract: Aircraft components utilize flexible fluted extruded twin wall plastic sheet to form aileron hinges, horizontal stabilizers and elevators, vertical stabilizers and rudders, compound landing gear, struts, and control systems which are lighter in weight and lower in cost than previously available structures. The landing gear has damping characteristics superior to previous gear. The invention is particularly well suited to remotely controlled flying model aircraft.

Landing and anchoring mechanism for an airship

Abstract: A landing and anchoring mechanism for an airship takes advantage of the ship's supporting frame that has a row of cross-ribs interconnected by lengthwise beams arranged between neighboring ribs. In order to make it possible to land on any landing field even without conventional and costly apparatus, and to anchor the airship against the effects of wind and weather, a bi-pod landing gear is combined with an anchoring device. The landing gear is articulately connected to the supporting frame on the one hand and to the airship gondola by respective landing gear lateral rocker arms on the other hand. The bi-pod landing gear is arranged in a crosswise plane in front of the aerodynamic center of wind pressure of the airship. At least a portion of the anchoring device is provided on the floor of the airship gondola in the area of the attachment of the landing gear lateral rocker arms to the gondola floor. The anchoring device is provided for connecting the airship with a mooring on the ground, whereby another portion of the anchoring device may be located on the ground.

Landing and mooring apparatus for an airship.

Abstract: The invention relates to landing and mooring apparatus for an airship (1) with an airframe consisting of a series of transverse girders (3) and longitudinal girders disposed therebetween. To allow the airship to land and to be secured against weather conditions without use of a mooring mast, it is proposed that a two-strut landing gear (5, 5), which is connected, in an articulated manner, on the one hand to the airframe and, on the other hand, by means of landing gear arms (15) in each case, to the airship gondola (2), and which is disposed in a transverse plane in front of the wind pressure centre of the airship, and an additional mooring device on the base of the airship gondola (2) in the vicinity of the connection of the landing gear arms (15) on the gondola base be provided for the connection of the airship to a mooring site.

Flight investigation of the use of a nose gear jump strut to reduce takeoff ground roll distance of STOL aircraft

Abstract: A series of flight tests was conducted to evaluate the reduction of takeoff ground roll distance obtainable from a rapid extension of the nose gear strut. The NASA Quiet Short-haul Research Aircraft (QSRA) used for this investigation is a transport-size short takeoff and landing (STOL) research vehicle with a slightly swept wing that employs the upper surface blowing (USB) concept to attain the high lift levels required for its low speed, short-field performance. Minor modifications to the conventional nose gear assembly and the addition of a high pressure pneumatic system and a control system provided the extendible nose gear, or 'jump strut,' capability. The limited flight test program explored the effects of thrust-to-weight ratio, storage tank initial pressure, and control valve open time duration on the ground roll distance. The data show that the predicted reduction of takeoff ground roll on the order of 10 percent was achieved with the use of the jump strut. Takeoff performance with the jump strut was also found to be essentially independent of the pneumatic supply pressure and was only slightly affected by control valve open time within the range of the parameters examined.

Landing gear for aircraft constructed with extruded fluted plastic sheet

Abstract: Aircraft components utilize flexible fluted extruded twin wall plastic sheet to form aileron hinges, horizontal staibilizers and elevators, vertical stabilizers and rudders, compound landing gear, struts, and control systems which are lighter in weight and lower in cost than previously available structures. The landing gear has damping characteristics superior to previous gear. The invention is particularly well suited to remotely controlled flying model aircraft.

Structure of rotating device of landing gear

Abstract: PURPOSE: To readily mount and demount with a simple structure of a rotary apparatus for a landing gear and accordingly fairly economically maintain it. CONSTITUTION: In a structure of a rotary apparatus of a landing gear of an aircraft, there is provided a modular assembly of one unit which is disposed in a wheel axle 1 of a wheel of the landing gear of the aircraft. This apparatus comprises a rotor 9 mounted in a stator 7 by a stator 7 and two rolling bearings. The stator 7 and rotor 9 are divided into two parts of the stator 7 and two parts of the rotor 9, respectively, and the two parts of the rotor 9 form an electric signal generator, and an electromagnetic coupling of a rotating transformer type for a sensor supported by a wheel, respectively.

Agfatl- active gear flexible aircraft takeoff and landing analysis

Abstract: The Active Gear, Flexible Aircraft Takeoff and Landing Analysis program, AGFATL, was developed to provide a complete simulation of the aircraft takeoff and landing dynamics problem AGFATL can represent an airplane either as a rigid body with six degrees of freedom or as a flexible body with multiple degrees of freedom The airframe flexibility is represented by the superposition of up to twenty free vibration modes on the rigid-body motions The analysis includes maneuver logic and autopilots programmed to control the aircraft during glide slope, flare, landing, and takeoff The program is modular so that performance of the aircraft in flight and during landing and ground maneuvers can be studied separately or in combination A program restart capability is included in AGFATL Effects simulated in the AGFATL program include: (1) flexible aircraft control and performance during glide slope, flare, landing roll, and takeoff roll under conditions of changing winds, engine failures, brake failures, control system failures, strut failures, restrictions due to runway length, and control variable limits and time lags; (2) landing gear loads and dynamics for up to five gears; (3) single and multiple engines (maximum of four) including selective engine reversing and failure; (4) drag chute and spoiler effects; (5) wheel braking (including skid-control) and selective brake failure; (6) aerodynamic ground effects; (7) aircraft carrier operations; (8) inclined runways and runway perturbations; (9) flexible or rigid airframes; 10) rudder and nose gear steering; and 11) actively controlled landing gear shock struts Input to the AGFATL program includes data which describe runway roughness; vehicle geometry, flexibility and aerodynamic characteristics; landing gear(s); propulsion; and initial conditions such as attitude, attitude change rates, and velocities AGFATL performs a time integration of the equations of motion and outputs comprehensive information on the airframe, state-of-maneuver logic, autopilots, control response, and aircraft loads from impact, runway roll-out, and ground operations Flexible-body and total (elastic plus rigid-body) displacements, velocities, and accelerations are also output in the flexible-body option for up to twenty points on the aircraft The AGFATL program is written in FORTRAN IV for batch execution and has been implemented on a CDC CYBER 170 series computer with an overlayed central memory requirement of approximately 141 (octal) of 60 bit words The AGFATL program was last updated in 1984

The Aluminum Falcon: a Low Cost Modern Commercial Transport

Abstract: The American Institute of Aeronautics and Astronautics (AIAA) released a Request For Proposal (RFP) in the form of an undergraduate design competition for a 153 passenger jet transport with a range of 3,000 nautical miles. The primary requirement for this aircraft was low cost, both in acquisition and operation, with a technology availability date of the year 2000. This report presents the Non-Solo Design Group's response to the RFP, the Aluminum Falcon (AF-1). Non-Solo's approach to development was to take the best elements of seven individual preliminary designs, then combine and refine them. The resulting aircraft meets or exceeds all requirements of both the RFP and the Federal Aviation Administration (FAA). Highlights include a revolutionary wing planform, known as an M-wing, which offers many advantages over a conventional aft swept wing. For example, the M-wing lessens the travel in the aircraft center of gravity caused by fuel being stored in the wing. It also reduces the amount of torque imposed on the center wing box because more of the lifting load acts near the fuselage joint, rather than behind it. In essence, the M-wing offers the best of both worlds: using a forward swept wing root places the aerodynamic center of the wing further forward and allows the landing gear to be placed without the use of a yahudi. At the same time, with the outboard section swept backward the tip retains an amount of aeroelastic dampening that is lost on a completely forward swept wing. The result is a wing which has many advantages of a straight, unswept wings without the severe compressibility effects at high Mach numbers. Other highlights include judicious use of composites, giving recognition to the importance of weight and its effect on aircraft cost and performance, and an advanced passenger entertainment system which can be used as a source of revenue for the airlines. This aircraft meets the low-cost doctrine with an acquisition cost of $29 million and a direct operating cost of 3.5 cents per seat mile. The AF-1 incorporates new ideas with existing technology to result in an aircraft that will retain market viability well into the next century.