The APR system is designed to eliminate the warhead charge in the air in case of an emergency rocket flight. The APR system issues a command to eliminate the warhead in the following cases:
- if the missile loses stability and the flight direction deviates from the trajectory set by gyro devices along the angles of pitch, yaw and rotation by more than ±10°;
- in case of abnormal operation of the program mechanism of gyro-horizon 1SB9 (emergency contact in 1SB9 device remains closed at the moment of system start-up);
- if the command to turn off the engine prematurely causes the missile to fall to a lower range than allowed;
- if the command to shut down the engine, which causes the missile to fall to a longer range, is received after the command to shut down the engine, which causes the missile to fall to a longer range than allowed;
- if the command to shut down the engine is not passed, up to 67.5 s.
Due to the fact that in a particular application of the missile may no longer be necessary to control some parameters of the missile's movement, the APR system allows for the selection of the controlled parameters of the missile's flight in the following combinations:
- control according to paragraphs 1, 2, 3, 5 - self-liquidation is disabled";
- control pursuant to paragraphs 1, 2, 3, 4, 5 - complete control";
- control in accordance with paragraphs 1, 2, 5 - range disabled".
The APR system provides the possibility of its complete shutdown.
The onboard equipment of the ADF system includes the following devices and cables:
- Device 1SB23 (BAD -3).
- Device 1SB24 (РВ-14).
- Ampoule battery 1SB25M.
- Executive element of a combat unit.
- 1SB26. Onboard cable network.
1SB23 is the main switching device of the APR system and provides:
- choosing the type of missile flight control;
- issuance of data on the state of the APR system prior to missile launch to the 2B26 test panel, and during the technical position check to the 2B25 test panel;
- locking of the ADF system's executive circuits and launching the system at a certain second of flight after the missile reaches a given altitude;
- receiving commands from the control system and converting these commands into a command to detonate the explosives in case of an emergency flight and to disable the automatic control system in case of a normal flight.
The 1SB24 high-altitude relay is used to provide high-altitude blocking of the APR system activation connected with the missile ascent to the height of 5000m and high-altitude blocking of the executive chains connected with the missile ascent to the height of 3000m.
The onboard battery 1SB25 (1SB25M) is a chemical source of single-acting current of ampoule design with the voltage of 27 plus 3 minus 2 volts with the maximum permissible current at discharge of at least 15A during 1s. To bring the battery into operation it is supplied with compressed air at a pressure of 11±1atm. Time of the battery in working condition from the moment of compressed air supply to the battery until the voltage 27V not more than 2 s (for 1SB25M not more than 7 s). To ensure performance in the temperature range from -40 ° C to 0 ° C (for 1SB25M from -40 ° C to -10 ° C) in the battery provides an electric heater 192W (for 1SB25M power 240W) at 27V DC voltage.
The executive element of the APR system destroys the HF charge when an emergency blast signal is received from the APR system.
The executive element is:
- for 8F44 HF - 8B53 fuse device
- for HF 8F14, 9H33, 9H33-1 - fuse device of special equipment remote control and automatic control
- for HF 3H8 - device UHF 9B62
- for HF 8F44G, 8F44G1 - safety executive mechanism I-214A
The 1SB26 on-board cable network of the APR system communicates the APR system devices among themselves and with the control system.