Patent GB-908361-A (GB)
Title: Improvements in convertible aircraft
Inventor: DANCIK PAUL JULIUS
IPC: B64C29/00
Filed: 1960-01-22
Abstract: 908,361. Convertible aircraft. BOEING AIRPLANE CO. Jan. 22, 1960, No. 2372/60. Class 4. An aircraft having a wing pivotally mounted thereon for tilting movement has control means provided for one or more of the following elements of the aircraft: ailerons, elevator, rudder and thrust producing means; wherein the control means control the operation of said one or more of said elements through connecting means; and mechanism is provided responsive to tilting of the wing of the aircraft to render said connecting means inoperative. The aircraft comprises a fuselage 10 and a main wing 11 and elevator 14, both capable of pivotal movement from the full-line positions, for normal flight to the dotted line positions for vertical landing and take-off. A fin 12 carries a rudder 13 and a fan 18, and a horizontal tail structure carries an elevator 14 and a fan 19. Propellers 15, 16 and the fans 18, 19 are driven through shafting from a pair of gas turbine engines 17. Controls for rudder 13 and fan 18. Rudder pedals 111 operate a linkage 114, 113 and 115 to adjust a bellcrank 116 pivotally mounted on aircraft structure. One arm of the bellcrank carries a shaft 117 on which are pivoted links 118 and 119 of equal length and of length equal to the associated bellcrank arm. A bellcrank 120 has one arm 138 connected to a rod 139 (to be described later), a second arm 121 connected by a link 122 to a rod 125 and to link 118 and a third arm 123 connected by a link 124 to a rod 131 and to link 119. A shaft 127 carries a bellcrank 126 and a cable quadrant 132, the former being connected through linkage 128-130 to rudder 13 and the latter being connected by a cable 133 and screw-andnut mechanism 134 to the pitch-adjusting mechanism of the blades of fan 18. Controls for elevator 14 and fan 19. The control stick 21 is mounted in a bracket 22 capable of fore-and-aft rocking movement about a transverse axis and connected by a rod 85 to one arm of a bellcrank 86, the other arm of which carries a shaft 87 on which are pivoted links 88 and 89 of equal length and of length equal to the associated bellcrank arm. A bellcrank 90 has one arm 141 connected to a rod 140 (to be described later), a second arm 91 connected by a link 92 to a rod 95 and to link 88, a third arm 93 connected by a link 94 to a rod 104 and to link 89, and a fourth arm 142 connected to a rod 143. A shaft 97 carries bellcranks 96 and 98 and a cable quadrant 105, the latter two members being connected respectively to rods 143 and 104. Bellcrank 96 is pivotally connected to rod 95 and a link 100 which, together with bellcrank 98, is pivotally attached to a further bellcrank 99 in turn connected by a linkage 101-103 to the elevator 14 for trimming thereof. The quadrant 105 is connected by a cable 106 and a screw-and-nut mechanism 107 to the pitch adjusting mechanism of the blades of fan 19. Controls for ailerons 20. Lateral movement of control stick 21 operates through linkage 23-25 on a lever 26 pivotally mounted on the airframe by a shaft 27, which carries also a further lever 28 having a cranked extension 28a which pivotally supports a bellcrank 29 in turn connected by a link 30 to lever 26. Extension 28a is connected to rod 140, referred to above, and a rod 31 connects bellcrank 29 to a bellcrank 32 loosely supported on the wing tilt axis A-A. Rods 83 and 84 are pivotally attached at their upper ends to wing structure forward of the wing tilt axis A-A and are pivotally attached at their lower ends to the forward ends of levers 28 and 77 (to be described later). A rod 145 is made fast to aircraft structure at one end by shaft 27 and is connected at its upper end to a bellcrank 144 loosely mounted on tilt axis A-A. A link 33 connects bellcrank 32 to a pin 34 on the end of a lever 35 pivotally mounted on wing structure by means, not shown. Pin 34 supports two links 36, 37 of equal length and of length equal to that of lever 35. A bellcrank lever 38 has one arm 39 connected to link 36 by a link 40 and another arm 41 connected to link 37 by a link 42. A rod 43 extends from the connection between links 37 and 42 to arm 44 of aileron cable quadrant 45, from which cables 46 and 47 extend to a quadrant 48 associated with each aileron 20 through linkage 50 and torque tube 52. Pitch adjusting mechanism for propellers 15, 16. Collective pitch lever 72 operates through linkage 73a, 74 on a lever 75 pivotally mounted on the airframe at 76 which also carries a further lever 77 having a cranked extension 77a which pivotally supports a bellcrank 78 in turn connected by a link 79 to lever 75. Extension 77a is connected to rod 139, referred to above, and a rod 80 connects bellcrank 78 to a bellcrank 81 loosely supported on the wing tilt axis A-A. As explained above, rod 84 is connected between lever 77 and a fixed point on the wing structure forward of axis A-A. A rod 82 connects bellerank 81 of a lever bar 60 which carries a pair of cable quadrants 58 and 59 each having cables 61, 62 connected to a jack 70 for collective pitch adjustment through mechanism 66-68 of the blades 63 of the propellers 15 and 16. The quadrants 58 and 59 have arms 56 and 57 connected by a bar 55 in turn connected by a lever 54 and rod 53 to the pivotal connection between links 36 and 40 referred to above. Effect of wing and elevator tilt upon control mechanisms. During normal forward flight the aircraft is controlled by ailerons, elevators and rudder, but when the wing and elevator are swung to the vertical postion, the ailerons and elevator and, due to vertical airflow, the rudder 13, are ineffective, so that rolling control is achieved by differential pitch control of propellers 15, pitching control by fan 19 and yaw control by fan 18. Wing tilt, acting through linkgae 145, 144, and 146-8 rocks bellcrank 38 to adjust the associated linkage to a position, Fig. 4 (not shown) that results in lateral movement of stick 21 operating, through rod 53, the propeller pitch mechanism instead of, through rod 43, the aileron control quadrant. Wing tilt also acting through links 83 and 84, levers 28 and 77 and links 140 and 137 adjust belleranks 90 and 120 respectively so that their associated linkages are adjusted to transfer fore-and-aft movement of stick 21 and movement of pedals 111 from operation of elevator and rudder to pitch adjustment of fans 19 and 18 respectively. With the wing and elevator in intermediate positions operation of stick 21 and pedals 111 will result in simultaneous operation of ailerons and propeller pitch adjusting mechanism; elevator and fan 19 and rudder and fan 18.