1900s Launch preparations for Soyuz 5 went smoothly and the frigid mid-winter weather at the cosmodrome moderated a bit on January 15, with temperatures climbing to −7 °C (19 °F).

A technician had to strip down to his underwear in the chilly winter air to be able to fit inside the instrument compartment and remove four bolts holding the regulator in place.

While this had occurred on various Vostok and Voskhod flights, it was a much more serious problem for Volynov, as the Soyuz service module was much larger than the small retropack the earlier vehicles employed.

When the Soyuz started aerobraking in the upper reaches of the atmosphere, the combined spacecraft sought the most aerodynamically stable position - nose forward, with the heavy descent module facing directly into the air stream with only its light metal entry hatch at the front to protect it.

[6] As the thermal and aerodynamic stresses on the combined craft increased, struts between the descent and service modules broke off or burned through before the hatch failed.

[6] There was one final problem in store for Volynov when the parachute cables partially tangled and the soft-landing rockets failed, resulting in a hard impact which broke some of his teeth.

[6] The capsule came down in the Ural Mountains at 200 km (120 mi) of the southwest of Kostanay, near Orenburg, Soviet Union, far short of its target landing site in Kazakhstan.

The Yastreb had a regenerative life support system in a rectangular white metal box placed on the chest and abdomen to facilitate movement through the Soyuz's hatchways.