Vostok 8A92M | IRS-1B
The Earth Science flight Vostok 8A92M | IRS-1B departed Baikonur Cosmodrome, Republic of Kazakhstan atop a Vostok 8A92M, bound for LEO.
- Launch time
- Status
- SUCCESS
- Operator
- Soviet Space Program
- Mission type
- Earth Science
- Rocket
- Vostok 8A92M
- Launch site
- Baikonur Cosmodrome, Republic of Kazakhstan
- Launch pad
- 31/6
- Payload
- —
- Target orbit
- LEO

Mission timeline
- 1991-08-29T06:48:43.000ZVostok 8A92M roars off the pad at Baikonur Cosmodrome, Republic of Kazakhstan.
- The vehicle reaches Max Q, the highest aerodynamic load of the flight.
- MECO — first-stage propulsion ends after a nominal burn.
- Clean stage separation confirmed.
- The upper-stage engine lights up after separation.
- Orbit insertion confirmed — now circling in LEO.
- All mission objectives achieved.