AltitudejVelocity Parameter System (SVSP)

The SVSP consisted of air data probes extended from Buran at an altitude of 20 km to measure barometric altitude, true and indicated airspeed, Mach speed, angle of attack, and dynamic pressure, and display that data for the commander and pilot in the cockpit. The SVSP was only supposed to correct the vertical channel of the inertial navigation system in emergency situations where other navigation aids failed, helping the crew to guide Buran to a manual touchdown. The SVSP was the equivalent of the Shuttle’s Air Data System.

High-Altitude Radio Altimeter (RVB) and Low-Altitude Radio Altimeter (RVM)

The RVB was designed for accurate measurements of geometrical altitude using the principle of impulse modulation of an emitted signal. Its information was only supposed to be used for actual flight trajectory changes when the orbiter flew over flat terrain (because the local relief was not necessarily at the same level as the runway) or in emergency situations, where it could have been used to provide elevation data in conjunction with the air data probes.

The RVM accurately measured the altitude above the runway from flare-out at an altitude of 20 m to touchdown as well as absolute flight altitude under 1 km. The RVB has no equivalent on the Shuttle, whereas the RVM performs the same role as the Shuttle’s Radar Altimeters.

The on-board and ground-based components of the RDS, RSBN, and RMS were known together as the Vympel (“Pennant’’) system and were developed by VNIIRA under the leadership of Gennadiy N. Gromov. Vympel also included three ground – based radar complexes that monitored the vehicle’s adherence to the calculated flight path during approach and landing. Each of the complexes contained two radars. The first complex (TRLK-10K or Skala-MK) acquired the vehicle at a distance of about 400 km, using both primary (skin-echo) and secondary (transponder) signals, with the transponder reply transmitting such data as altitude, speed, and heading. At a distance of about 200 km an intermediate-range radar complex (E-511 or Ilmen) took over flight path monitoring. Precision approach radars (E-516V or Volkhov- P) monitored the final approach and landing [24].