And now a larger addition to finish the story of Pr.1141-related unbuilt projects.
Roughly at the same time when Pr.1141P PSKR's were designed (see page 2), so in the first half of the 1970s, works were started on a larger MPK code-named Orlik with more missile-oriented armament. Eventually the design was to be armed with RPK-6 Vodopad ASW missile and what sources describe as Kinzhal SAM missile. It is worth noting that the development of the Tor missile (which evolved into 3K95 Kinzhal) has actually begun only in 1975 and the source drawing shows a somewhat different arrangement (actual Kinzhal has missiles stored in VLS launchers while the available drawing of Orlik shows a launcher more similar to US Mk.13 but with twin missile rail) and apparently much smaller than the finally-built Kinzhal (which can be installed on ships with displacement of at least 800 tonnes). Sources' text also mention 400mm torpedo launchers but their location is unclear.
In 1979 works have begun on missile fast attack craft based on 1141/11451 family, designated as Pr.11452. Two variants were planned - one with two pairs of Moskit launchers and another with as much as 20 (!) Uran launchers (in addition to standard set of AK-176 and AK-630 guns etc.), though unfortunately available sources show only Moskit-armed variant. Designs works showed eventually that Moskit would be too big for this project and design was re-evaluated in 1983 to be armed with Urans plus Kortik air-defence system (then under development).
Below is the Moskit-armed version. It should be noted that sources mention the Kortik as it's SAM armament, yet it's development has only begun around that moment (1979) and the source drawing shows a launcher resembling rather Osa complex, which I therefore decided to use instead.
In 1985-1987 further stage of works started, this time again on ASW ship designated Pr.11455, armed with Medvedka ASW complex and Kortik air-defence system. It had also heavily redesigned wings arrangement.
To be honest, I can't say I'm happy with the way I drawn the "folded" wings, which ended up looking rather blurry. Sorry for that
After the fall of Soviet Union the newly-independent Republic of Ukraine "inherited" two unfinished Pr.11451 hulls. Eventually the idea was conceived to finish them as missile fast attack craft (MRK) armed with Uran missiles, designated Falkon-500.