View source for Engineering:SU-85

{{Infobox weapon
| name = SU-85
| image = SU-85 tank destroyer at the Muzeum Polskiej Techniki Wojskowej in Warsaw.jpg
| image_size = 300
| caption = SU-85 tank destroyer in Polish Army Museum.
| origin = Soviet Union
| type = [[Engineering:Self-propelled anti-tank gun|Self-propelled anti-tank gun]]
| is_vehicle = yes
| service = 1943-1950s (USSR)
| wars = [[Social:World War II|World War II]]
| designer = Lew S. Trojanow
| design_date = 1943
| production_date = 1943-1944
| number = 2,650
| variants = See [[Engineering:SU-85#Variants|Variants section]]
| length = {{convert|8.15|m|ftin|abbr=on}} overall<br />{{convert|6.10|m|ft|abbr=on|sigfig=1}} hull only
| width = {{convert|3.00|m|ftin|abbr=on}}
| height = {{convert|2.45|m|ft|abbr=on|sigfig=1}}
| weight = 29.6 tonnes (65,256&nbsp;lbs)
| suspension = [[Engineering:Christie suspension|Christie]]
| clearance = 0.40 m
| fuel_capacity = 460 L <br /> 810 L - 900 L (with additional fuel tanks)
| speed = 55&nbsp;km/h (34&nbsp;mph) (road)
| vehicle_range = Road: <br />{{convert|280|km|mi|abbr=on}}<br />{{convert|400|km|mi|abbr=on}} (with additional fuel tanks) <br /> Cross-country: <br /> {{convert|140|km|mi|abbr=on}}<br />{{convert|200|km|mi|abbr=on}} (with additional fuel tanks) <ref>Soviet Tanks and Combat Vehicles of World War Two (Steven J. Zaloga, James Grandsen) page 179.</ref>
| primary_armament = 85&nbsp;mm (3.34&nbsp;in) D-5T gun
| secondary_armament = none
| armour = 45&nbsp;mm(1.77&nbsp;in){{clarify|date=March 2020}}
| engine = Kharkiv model V-2 V-12 diesel engine
| crew = 4 (commander, driver, gunner, loader)
| engine_power = 493 hp (500 PS, 368&nbsp;kW)
| pw_ratio = 16.7 hp/tonne (12.43&nbsp;kW/tonne)
}}

The '''SU-85''' (''Samokhodnaya ustanovka'' 85) was a [[Place:Soviet Union|Soviet]] self-propelled gun used during [[Social:World War II|World War II]], based on the chassis of the [[Engineering:T-34|T-34]] medium tank. Earlier Soviet self-propelled guns were meant to serve as either assault guns, such as the [[Engineering:SU-122|SU-122]], or as [[Engineering:Tank destroyer|tank destroyer]]s; the SU-85 fell into the latter category. The designation "85" means the bore of the vehicle's armament, the 85&nbsp;mm D-5T gun.

== Development history ==
Early in [[Social:World War II|World War II]], Soviet tanks such as the [[Engineering:T-34|T-34]] and KV-1 had adequate firepower to defeat any of the German tanks then available. By the fall of 1942, Soviet forces began to encounter the new German [[Engineering:Tiger I|Tiger tank]], with armor too thick to be penetrated by the 76.2&nbsp;mm guns used in the T-34 and KV tanks at a safe range.<ref name="The Russian Battlefield">{{cite web|url=http://www.battlefield.ru/content/view/64/44/lang,en/|title=Самоходная установка СУ-85|work=BATTLEFIELD.RU - всё о Великой Отечественной войне}}</ref> The Soviet command also had reports of the Panther tank, that was in development then and possessed thicker armor than the Tiger; both represented an advance in German tank design. Although the Panther was not seen in combat until July 1943, the new generation of German vehicles meant the Red Army would need a new, more powerful main gun for their armoured formations.

In May 1943, work was begun on a new [[Engineering:Anti-tank gun|anti-tank gun]]. Military planners directed the design bureaus of both Gen. Vasiliy Grabin and Gen. Fyodor Petrov to modify the 85&nbsp;mm anti-aircraft gun for use as an anti-tank weapon. Petrov's bureau developed the D-5 85&nbsp;mm gun. Though much too large for the T-34 or KV-1 turret, it was thought the gun could be mounted upon the chassis of the [[Engineering:SU-122|SU-122]] self-propelled gun to give the weapon mobility. The version of this gun intended to be mounted upon the SU-85 was called the D-5S, with the "S" standing for self-propelled. Initially the production factory at Uralmash rejected the proposed design. Nevertheless, the administrators at Uralmash were persuaded to proceed, and the new design was put into production. The weapon was later modified to include a [[Engineering:Telescopic sight|telescopic sight]] and a new ball gun mantlet. This vehicle was retitled the SU-85-II.<ref name="The Russian Battlefield"/>

== Description ==
The SU-85 was a modification of the earlier [[Engineering:SU-122|SU-122]] self-propelled howitzer, essentially replacing the 122&nbsp;mm M-30S howitzer of the SU-122 with a D-5T high-velocity 85&nbsp;mm antitank gun. The D-5T was capable of penetrating the [[Engineering:Tiger I|Tiger I]] from 1000 m.<ref name=RuBF>{{cite web|last1=Potapov|first1=Valeri|title=JS-1 and JS-2 Heavy Tanks|url=http://english.battlefield.ru/tanks/10-heavy-tanks/19-js-2.html|website=The Russian Battlefield|access-date=2015-08-28|archive-date=2018-12-26|archive-url=https://web.archive.org/web/20181226184252/http://english.battlefield.ru/tanks/10-heavy-tanks/19-js-2.html|url-status=dead}}</ref> The vehicle had a low profile and excellent mobility. Initially given an armored commander's cap on the first batch, the SU-85's observational optics were improved by the introduction of a standard commander's cupola - the same as on the T-34/76 model 1942 - in addition to the already existing prismatic observation sights installed in left side and rear. On later vehicles, the same optics were added, allowing all-around observation.<ref>{{cite web|last1=Boldyrev|first1=Eugeni|title=SU-85 Tank Destroyer|url=http://english.battlefield.ru/tanks/11-spg/31-su-85.html|website=The Russian Battlefield|access-date=2015-08-28|archive-date=2018-04-01|archive-url=https://web.archive.org/web/20180401004421/http://english.battlefield.ru/tanks/11-spg/31-su-85.html|url-status=dead}}</ref>

== Production history ==
[[File:Su-85 TBiU 8 2.jpg|thumb|left|SU-85 (1944)]]
SU-85 production started in mid-1943, with the first vehicles reaching their units by August. When the up-gunned T-34-85 medium tank entered mass production in the spring of 1944, there was no point in continuing production of a tank destroyer without superior firepower.<ref>(Zaloga 1984:181, Perrett 1987:84)</ref> In light of this, SU-85 production was stopped in late 1944 after 2,650 vehicles had been produced. It was replaced on the production lines by the [[Engineering:SU-100|SU-100]] tank destroyer, armed with the more powerful 100&nbsp;mm D-10S gun, but due to delays with 100&nbsp;mm ammo, a stopgap version called SU-85M appeared in September 1944, which was SU-100 fitted with 85&nbsp;mm gun, already with thicker frontal armor and commander's cupola.

== Service history ==
The SU-85 entered combat in August 1943. It saw active service across the Eastern Front until the end of the war. Though a capable weapon, it was found that its 85&nbsp;mm weapon was not adequate to penetrate the armour of the larger German armoured fighting vehicles.{{Citation needed|reason=Contrary to ballistic data on D-5T's page itself, showing penetration capacity of 100mm at 1k range. End of production was due to introduction of T-34/85 making SU-85 a redundant platform, as noted in this very page itself.|date=February 2020}} It was replaced by the SU-100.

The SU-85 was withdrawn from Soviet service soon after the war, and was exported to many Soviet client states in Europe and elsewhere. Some SU-85s were converted to use as command and recovery vehicles.<ref>(Perrett 1987:85)</ref> Countries such as North Korea and Vietnam kept it in service for many years.<ref>(Perrett 1987:84)</ref>

== Variants ==
=== Former Soviet Union ===
* '''SU-85''' Basic version with four periscopes and no commander's cupola.
* '''SU-85M''' SU-100-like cupola and thicker frontal armor. 315 built.

=== Poland ===
* '''WPT-34''' (1960s) - Polish repair and maintenance vehicle with a superstructure replacing the casemate, a crane, a large-diameter telescoping snorkel for deep fording operations as well as a large-spade type [[Engineering:Earth anchor|earth anchor]] in the rear. It was converted from SU-85 tank destroyers as well as T-34 medium tanks and SU-100 tank destroyers.

== Operators ==
* {{flag|Bulgaria}}
* {{flag|Czechoslovakia}}
* {{flag|Hungary}}
* {{flag|North Korea}}
* {{flag|Poland}}
* {{flag|Romania}} – 26 armored recovery vehicles based on the SU-85 were received by 1 January 1956<ref>{{cite journal |last=Sămușan |first=Alin |date=2017 |title=Contribuții la istoria dotării cu armament a armatei române între 1944 și 1959 |trans-title=Contributions to the history of the Romanian army's weaponry endowment from 1944 to 1959 |url=https://www.academia.edu/37411353 |language=ro |journal=Bulletin of the National Military Museum |volume=15 |access-date=June 28, 2021}}</ref>
* {{flag|Soviet Union}}
* {{flag|Vietnam}}
* {{flag|Yugoslavia}}
* {{flag|East Germany}} from 1952/56 until 1962<ref>:de:Liste der Technik und Bewaffnung der NVA#Panzer</ref>{{Circular reference|date=March 2019}}

==See also==
* List of Soviet tanks - covers all periods
*[[Engineering:ASU-85|ASU-85]]
*[[Engineering:SU-100|SU-100]]

===Tanks of comparable role, performance and era===

* Germany – StuG III, StuG IV and Jagdpanzer IV
* Italy – Semovente da 75/34
* Romania – Mareșal
* United Kingdom – SP 17pdr, A30 (Avenger)
* United States – M10 GMC

== References ==
{{reflist}}

==Sources==
* Perrett, Bryan (1987). ''Soviet Armour Since 1945,'' London: Blandford. {{ISBN|0-7137-1735-1}}.
* Zaloga, Steven J., James Grandsen (1984). ''Soviet Tanks and Combat Vehicles of World War Two,'' London: Arms and Armour Press. {{ISBN|0-85368-606-8}}.

==External links==
{{Commons|SU-85}}
*[http://english.battlefield.ru/su-85.html SU-85] at Battlefield.ru{{dead link|date=February 2020}}
*[http://www.wwiivehicles.com/ussr/tank-destroyers/su-85.asp SU-85] at WWIIvehicles.com


[[Category:Tracked self-propelled artillery]]

{{Sourceattribution|SU-85}}