Stand-by HSI displays aircraft position, heading & pitch with respect to the radio beacon & four cardinal points. The indicator comprises sealed electromechanical part and Control & Monitor Unit (BUK-14).

SPECIFICATIONS
Error of current heading, relative bearing of radio beacon         
and selected heading                                                                 ±1° max
Error of distance counter:
                                 - 0-25 km                                                   ±1 km max
                                 - 25-999 km                                               ±3 km max
 Slaving rate of pointers of:
                                - current heading                                        30 °/sec
                                - relative bearing of radio beacon               60 °/sec
                                - selected heading                                      40 °/sec
                                - distance                                                   15 km/sec
Readiness time                                                                          1 min max
Weight                                                                                       2,3kg max