Editing Almaz (section)

==Development==
[[Vladimir Chelomey]] at the [[NPO Mashinostroyeniya|OKB-52]] design bureau promoted Almaz as a response to the U.S. Air Force's [[Manned Orbiting Laboratory]] (MOL) project. MOL had been widely publicized in the American press in the early 1960s, which provided Chelomei plenty of material to use to lobby for a Soviet response.{{citation needed|date=April 2021}}

The Almaz space station program involved three major hardware components:
* Orbital Piloted Station (OPS, 11F71) module, forming the space station core,<ref name=RSWops/>
* [[Functional Cargo Block]] (FGB, 11F77), intended as resupply craft for the stations,<ref name=RSWtks/> and
* [[VA spacecraft]] (11F74, known in the West as the ''Merkur'' spacecraft), intended as launch and return vehicle for the crews,<ref name=RSWtks/> and reusable for up to 10 flights.

The OPS would have a maximum diameter of {{convert|4.15|m}}, a mass of roughly {{convert|20|t}}, and an internal habitable volume of {{convert|47.5|m3}}.<ref name=RSWops/>

Much like its [[Manned Orbiting Laboratory|MOL]]/[[Project Gemini|Gemini]] counterpart, the initial Almaz APOS space station design called for the launch of an Almaz-OPS space station and a [[VA spacecraft|VA return craft]] containing its initial three-man crew, mated together as OPS/VA atop Chelomei's UR-500 [[Proton (rocket family)|Proton rocket]].<ref name="EAapos">{{Cite web |editor-last=Wade |editor-first=Mark |title=Almaz APOS |url=http://www.astronautix.com/a/almazapos.html |url-status=live |archive-url=https://web.archive.org/web/20240509050500/http://www.astronautix.com/a/almazapos.html |archive-date=May 9, 2024 |access-date=August 31, 2012 |publisher=[[Encyclopedia Astronautica]] }}</ref> As with MOL/Gemini, once in orbit the crew would access the laboratory through a hatch in the heat shield at the bottom of the VA capsule. After an extended stay of 30 to 60 days of military observation and photography, the crew would return to Earth by way of a VA return vehicle.<ref name="RSWorigin">{{Cite web |last=Zak |first=Anatoly |title=Origins of the Almaz project |url=https://www.russianspaceweb.com/almaz_origin.html |url-status=live |archive-url=https://web.archive.org/web/20121009023440/http://www.russianspaceweb.com/almaz_origin.html |archive-date=October 9, 2012 |website=RussianSpaceWeb.com }}</ref><ref name="EAtks">{{Cite web |editor-last=Wade |editor-first=Mark |title=TKS |url=http://www.astronautix.com/t/tks.html |url-status=live |archive-url=https://web.archive.org/web/20240211031537/http://www.astronautix.com/t/tks.html |archive-date=February 11, 2024 |access-date=August 31, 2012 |website=[[Encyclopedia Astronautica]] }}</ref>

Unlike the American MOL design, the Soviets designed the Almaz to be recrewed and resupplied. For this, they created the [[TKS (spacecraft)|TKS resupply craft]] (11F72), which consisted of an FGB and a VA return craft to carry the crew, also launched together on a Proton rocket. At the station, one [[Docking and berthing of spacecraft |docking port]] would be available to receive the TKS craft once the previous crew had left the station in their VA capsule.<ref name=RSWtks/>

While the MOL was cancelled in 1969, the Almaz program was integrated into the [[Salyut programme|Salyut program]] and resulted in three flown space stations, two of which were crewed successfully. As "man-rating" the VA spacecraft and the Proton rocket took longer, the first phase called for the launch of three Almaz stations without the VA spacecraft, with the crew instead launched separately by Soyuz rocket in a modified Soyuz spacecraft. Plans called for the first three Almaz stations to be visited by three two-month-long expeditions each. This was realized fully by two missions and partially by one; however, the initial intention of launching Almaz APOS and the TKS spacecraft together with its crew in VA spacecraft would never materialize during the program, and neither would the TKS craft play its intended role as resupply craft. The Almaz APOS design, without VA spacecraft, would evolve into the Almaz OPS station cores of the Salyut program.<ref name="RSWhist">{{Cite web |last=Zak |first=Anatoly |title=History of the Almaz space stations |url=https://www.russianspaceweb.com/almaz_development.html |url-status=live |archive-url=https://web.archive.org/web/20121009083157/http://www.russianspaceweb.com/almaz_development.html |archive-date=October 9, 2012 |website=RussianSpaceWeb.com }}</ref>

===Defense measures===
In addition to reconnaissance equipment, Almaz was equipped with a unique [[Rikhter R-23|23mm Rikhter]] (factory index 261P or 225P) rapid-fire cannon mounted on the forward belly of the station. This revolver cannon was modified from the tail-gun of the [[Tupolev Tu-22]] bomber and was capable of a theoretical rate of fire of 1800-2000 (up to 2600) rounds per minute. Each 168&nbsp;gram (ammo 23-OFZ-D-R ) or 173&nbsp;gram (ammo 23-OFZ-G-R) projectile flew at a speed of 850&nbsp;m/s relative to the station. The cannon was tested at the end of the mission by firing 20 rounds, when the station was operating in uncrewed mode. To aim the cannon, which was on a fixed mounting, the entire station would be turned to face the target.<ref name="ars-2015117">{{Cite news |last=Gallagher |first=Sean |date=November 17, 2015 |title=Russian television reveals another secret: the Soviet space cannon |url=https://arstechnica.com/information-technology/2015/11/russian-television-reveals-another-secret-the-soviet-space-cannon/ |url-status=live |archive-url=https://web.archive.org/web/20230525144255/https://arstechnica.com/information-technology/2015/11/russian-television-reveals-another-secret-the-soviet-space-cannon/ |archive-date=May 25, 2023 |work=[[Ars Technica]] }}</ref> The Almaz series are the only known armed, crewed military spacecraft ever flown.

[[Salyut 3]]/OPS-2 conducted a successful remote test firing with the station uncrewed due to concerns over excessive vibration and noise.

OPS-4 was to have featured two rockets instead of the aircraft cannon, but this system has not been shown publicly and may have never been fully manufactured despite it being used experimentally.{{citation needed|date=April 2021}}