give the ability of launching manned space vehicles "Soyuz"
of a greater mass comparing to "Vostok" (initially 5.8 t
and then 6.5 t instead of 4.8 t.), the "Vostok" had to be
modified. Mainly, stage III was a matter of concern. Stage
E on LV "Soyuz" was replaced with stage I with LV "Molniya".
Further modifications of launch vehicles derived from rocket
R-7 were made by the Central Specialized Design Office (D.
I. Kozlov) to which all documentation on the R-7 derived
rockets was passed on.