I have been debating whether to post this here or to put it in the Q&A section or simply put it in the Russian section on here. Since it is about history I have decided to post the piece here and then keep fingers crossed.
The Zenit-2 and Zenit-4 were the Soviet Union's first series of photoreconnaissance satellites, first flying in 1961 (briefly - the launch vehicle failed!) and 1963 respectively. Both satellites were designed and developed by Korolyov's bureau but at some time during the 1964-1965 period the manufacture and further development of these satellites was handed over to Kozlov's team in Samara.
Are there any Russian publications which specifically say (a) when the Zenit-2 and Zenit-4 productions were passed to Samara (probably not at the same time) and (b) which were the first Samara-manufactured Zenit-2 and Zenit-4 satellites to be launched? Chertok's memoirs say that the development of testing of Zenit-4 was done within the Korolyov bureau, so maybe it was only passed to Samara when the system was declared to be operational, sometime after the Zenit-2 had made the transition?
Of course, it could be that such precise information has not been published by the Russians - I am willing to believe that.
One other thing. The majority of the photoreconnaissance satellite series had what I call "Ministry names": for example, the Zenit-2M was Gektor and Zenit-4M Rotor. However no Ministry names appear to have been assigned to Zenit-2 and Zenit-4. Was this simply because the practice of using such names had not been established in 1961-1963 when the launches started in these programmes?
Any gap-filling or thoughts would be appreciated, please.
https://www.samspace.ru/upload/iblock/835/kosmicheskoe_apparatostroenie.pdfAccording to RKTs Progress' satellite history (link above, p. 20) the first Zenit-2 serially built by the Progress factory in Kuibyshev was Kosmos-9, launched on 27 September 1962.
On p. 21 the text says:
"On 16 November 1963 the first Zenit-4 was launched... In 1964, beginning with satellite nr. 14, serial production and development of automated low-orbiting remote sensing satellites (read : photorecon) was turned over to branch nr. 3 of OKB-1, headed by D.I. Kozlov, and to the Kuibyshev factory Progress".
Not sure if nr. 14 is a Zenit-2 or Zenit-4. Should check further.
"In 1964, beginning with satellite nr. 14, serial production ... to the Kuibyshev factory Progress".
Zenit 2 14L was launched 1963 (failure)
Zenit 4 14L 1966
They are talking about Zenit 4.