Patent GB-802213-A (GB)
Title: Helicopter flight simulator and pilot training device
IPC: G09B9/46
Filed: 1956-04-04
Abstract: 802,213. Training apparatus for helicopter pilots. BELL AIRCRAFT CORPORATION. April 4, 1956 [Sept. 30, 1955], No. 10267/56. Class 4. A helicopter flight simulator and pilot trainer comprises a simulated cockpit 26 provided with rudder pedals 300 ; a cyclic pitch control lever 302 ; a collective pitch control lever 304 ; an engine throttle control 306 and an instrument display 328, which is duplicated at the instructor's station 29 and consists of an engine manifold pressure gauge, tachometers, air speed indicator, altimeter and compass. A sound generating device 350 is provided to reproduce engine sounds thereby giving the student pilot an indication of change in engine speed and in addition an unbalanced mass type motor 355, Fig. 1, is provided to simulate main rotor vibration. The rudder pedals 300 control a potentiometer 325, Fig. 1, and controls 302, 304 and 306 operate respectively potentiometers 312 and 313, 314 and 322, Figs. 1 and 23. The potentiometers supply signals to an electromechanical analogue computer 28 which is supplied also from a unit 340 at an instructor's station 29 with signals such as wind velocity and direction, temperature, gross weight, C.G. position and rough air. The rough air simulating unit, Fig. 24 (not shown), comprises a motor driving a series of eccentrically arranged cranks which operate a bank of potentiometers to supply random signals representing rough air conditions. The cockpit 26 faces a part-spherical screen 27 and images of sky and ground are projected on to the screen by three projection units P1, P2 and P3 controlled by the output from the computer 28. Unit P1 comprises a revolving drum formed with a transparency T illuminated by a fixed light-source K to project the horizon simulations which appear at all times to remain in the far distance unchanged in size. The drum is arranged to yaw about axis VV when the main projector P2 yaws about its axis ZZ, Fig. 2. Projector P2 comprises a transparency 125 illuminated by an arc lamp L1 and two miniature filament lamps L2 and L3 to project the rear scenery of a flying field. The specification includes detailed description of a preferred embodiment of the projectors P1 and P2, but Fig. 4 shows diagrammatically the movements imparted to the transparencies and the lamps. The projection system is mounted above the student pilot on frame members 30 by means of a gimbal 31 connected through gearing 42 to a " pitch motor 44 and through gearing 46 to a " roll motor 47. Shaft 33 carries a relatively rotatable support post 34-35, the lower end of which carries a rigidly mounted housing 36 formed with slideways 37 for a frame 38. Further sideways 39 on frame 38 carry the transparency 125 and mechanism (not shown) responsive to signals from computer 28 is provided for creating relative movement between the slideways and frame 38, thereby moving the transparency relative to the light source shown at 60 to give the student pilot the illusion of translational flight. An illusion of yawed flight is imparted by rotation of post 34- 35 through gearing 49 from a motor 48. Synchronous rotation of transparency P1 is achieved by a chain and sprocket drive 75. The light source 60 is mounted on a tube 62 mounted for vertical sliding movement in post 34-35 under the action of a motor 64 to give the illusion of change of altitude and a blower is mounted on the top of tube to cool lamp 60. Whereas projector P2 is intended as a " hovering " projector to simulate terrain from touchdown to 55 feet of altitude, projector P3 is intended as an " autorotation " projector to simulate terrain from 55 feet to 500 feet of altitude and only one of the two projectors is operative in combination with projector P1 at any given time for scenery projection. A construction of projector P3 is shown in Fig. 14 wherein a cranked arm 177, supporting the transparency of projector P2, carries a base frame 180 provided with a transversely movable carriage plate 182 which supports a cantilever arm 188 having at its forward end a bracket 189 carrying a support shaft 190 to which is secured the framework 192 for transparency 175. A screw and nut mechanism 202 operated by a motor 208 causes frame 192 to traverse arm 188 and a similar mechanism is used to traverse the frame laterally of the arm, such movements being supplemental to the movements imposed on projector P2 on which projector P3 is mounted. The light source 230 is mounted for relative vertical movement with respect to transparency 175 and a blower 260 is provided to cool the lamp. Mechanism, Fig. 22 (not shown), is provided to apply a simulated landing shock to the cockpit at touch-down and a manual control station 345, Fig. 1, may be used to operate the servo motors controlling the various mechanisms independently of the computer 28.