Patent GB-1334108-A (GB)
Title: Training simulator with malfunction insertion
IPC: G09B9/08
Filed: 1971-10-06
Abstract: 1334108 Aircraft training simulators SINGER CO 6 Oct 1971 [30 Oct 1970] 46394/71 Heading G4G A training simulator comprises a computer for simulating operational characteristics of a system, e.g. an aircraft, and storage means for reference values of certain variable output parameters of the system which can be compared with the actual values of these parameters whereby a given difference may be used to generate a malfunction signal. Two kinds of malfunction may be simulated viz.:-those which occur automatically when certain conditions are met and those rendered probable by certain conditions. As an example of the first kind, loss of oil pressure under certain conditions of A/C roll, is given. The roll output of the computer is compared with a reference roll value (Fig. 2, not shown) and the output of the comparator integrated. The integrated signal is subtracted from the oil-pressure output signal of the computer whereby the reading of the oil-pressure guage drops, indicating a malfunction. Simulation of malfunctions of the second kind may be inserted into the system at the will of the supervisor using the circuit of Fig. 4 which selects each of e.g. four malfunctions one at a time in random order. As shown, all four malfunctions depend upon different combinations of the outputs of comparators 37, Fig. 4, which compare the three computer outputs corresponding to altitude, airspeed and pitch, with various reference values. The four malfunctions are associated with four AND gates 39 each of which gives an output when the required conditions are signalled by the inputs from the comparators. The output of each gate 39 is fed to a corresponding second AND gate 41. Malfunction selection is initiated by operating switch 43 which disables AND gates 41 and feeds clock signals to a four-bit counter 45. Release of the switch stops the counter and causes one of four latches 47 to operate and provide an input signal to a corresponding one of the AND gates 41. At the same time, the input signals to gates 41 from the switch 43 is restored. Thus only one of the second malfunction gates 41 will operate and only if the required conditions are signalled by the corresponding first gate 39. The outputs of gates 41 are connected to a warning lamp 49 by an OR gate 51. Each latch 47 contains an AND gate 61, Fig. 5, having inputs from the counter 45 and from a flip-flop 63 (assumed in "0" state). A second AND gate 67 receiving the output of gate 61 and a signal from the normally-closed reset switch 53. The output of gate 67 provides an input to a corresponding gate 41, and at the same time, re-sets the flip-flop 63 whereby the gate 61 is disabled. Gate 67, however, continues to operate by virtue of the feedback indicated and is not disabled until the supervisor opens reset switch 53 after the required malfunction has occurred. The latch 47 (and the corresponding malfunction) cannot again be selected until the other three have operated. When all four latches have operated, each will supply a signal from the "1" output of flip-flop 63 to an AND gate 57 which thereupon sets each flip-flop over line 71.