Patent GB-1311120-A (GB)
Title: Aircraft bomsight instrument
IPC: B64D1/04
Filed: 1970-07-07
Abstract: 1311120 Aircraft bombsight SAAB-SCANIA AB 7 July 1970 [9 July 1969] 32869/70 Heading F3C An aircraft bombsight instrument for automatically releasing bombs against a target 3 during an attack thereagainst, comprises an optical sight for directing the aircraft against the target during a directing and measuring phase of a dive attack. Transducer means 8, 9, 10 which measure flight data and convert it into electric signals are provided. A computer 7 is connected to the transducer means for computing the point of time during a release phase of the dive attack at which the bombs are released to hit the target. At the point of time the computer 7 gives a release signal to a release means 13 for providing a release impulse to a bomb release mechanism 14. The optical sight ineludes a sight line indicator 6 connected to the computer 7 and positioned in the pilot's line of sight 4, the indicator having a reflection glass 5 on which is displayed a sighting mark 21 which preferably comprises a pair of parallel lines 26 having a dot 25 interposed therebetween and a visual symbol 20 indicating the velocity vector of the aircraft. The sighting mark 21 and visual symbol 20 are interconnected during the measuring phase and also preferably the directing phase so as to form a combined sight symbol 21a. The transducer means includes a flight position transducer 9 for continuously measuring the attitude angles of the aircraft, acceleration transducers 10 for continuously measuring the accelerations of the aircraft along the co-ordinate axes of the aircraft. A Doppler equipment 11 is provided for measuring the velocity of the aircraft relative to the ground and also a device, e.g. a radar unit 12, for continuously measuring along the line of sight 4 the distance from the aircraft to the target. The computer 7 is operable to compute continuously a speed vector of the aircraft which is referenced to the ground, and during the directing phase and the measuring phase on the basis of the transducer means, the computed ground referenced speed vector, to compute continuously a position vector for the target relative to the aircraft and filtered values of the velocity components of the target including corrections of measured wind components, and during the release phase on the basis of the position vector of the target, the ground referenced speed vector of the aircraft, the target speed components and the target speed vector including wind correction computed during the measuring phase, the acceleration vector of the aircraft, data of bomb ballistics and the attitude angles of the aircraft continuously measured by the flight position transducer to continuously compute a banking and pull-up manoeuvre for the aircraft so that the predicted ground impact error of the bombs in the horizontal plane along as well as crosswise the direction of flight will be equal to zero at the point of time predicted by the computer for releasing the bombs from the aircraft.: The sight line indicator 6 is operable to present to the pilot during the release phase a banking and pul-up command corresponding to calculated manoeuvres in such a way that the visual command displayed can be brought to zero by the pilot at said point of time of bomb release by the pilot in his manoeuvrings of the aircraft.