Mars 1M No.2 (Korabl 5)
The Soviet probe Korabl 5 (1M No. 2) was destroyed on October 14, 1960, during its launch to Mars after a catastrophic third-stage (Block I) failure at T+290 seconds. A liquid oxygen leak froze the kerosene in the turbopump, preventing ignition and forcing a suborbital re-entry over Siberia.