Editing Contra-rotating propellers (section)

===USSR, Russia and Ukraine===
[[File:Kuznetsov NK-12M turboprop on Tu-95.jpg|thumb|left|One of the four contra-rotating propellers on a [[Tu-95]] Russian strategic bomber]]

In the 1950s, the Soviet Union's [[Kuznetsov Design Bureau]] developed the [[NK-12]] turboprop. It drives an eight-blade contra-rotating propeller and, at {{convert|15000|hp|kW|adj=pre|shaft|abbr=off}}, it is the most powerful turboprop in service. Four NK-12 engines power the [[Tupolev Tu-95]] ''Bear'', the only turboprop bomber to enter service, as well as one of the [[fastest propeller-driven aircraft]]. The [[Tupolev Tu-114|Tu-114]], an airliner derivative of the Tu-95, holds the world speed record for propeller aircraft.<ref>{{cite web |url=http://records.fai.org/general_aviation/current.asp?id1=21&id2=3 |website=Fédération Aéronautique Internationale (FAI) |title=General aviation world records |archive-url=https://web.archive.org/web/20071007145139/http://records.fai.org/general_aviation/current.asp?id1=21&id2=3 |archive-date=October 7, 2007 |url-status=dead}}</ref> The Tu-95 was also the first Soviet bomber to have intercontinental range. The [[Tupolev Tu-126|Tu-126]] AEW aircraft and [[Tupolev Tu-142|Tu-142]] maritime patrol aircraft are two more NK-12 powered designs derived from the Tu-95.

The NK-12 engine powers another well-known Soviet aircraft, the [[Antonov An-22]] Antheus, a heavy-lift cargo aircraft. At the time of its introduction, the An-22 was the largest aircraft in the world and is still, by far, the world's largest turboprop-powered aircraft. From the 1960s through the 1970s, it set several world records in the categories of maximum payload-to-height ratio and maximum payload lifted to altitude.

Of lesser note is the use of the NK-12 engine in the [[A-90 Orlyonok]], a mid-size Soviet [[ekranoplan]]. The A-90 uses one NK-12 engine mounted at the top of its T-tail, along with two turbofans installed in the nose.

In the 1980s, Kuznetsov continued to develop powerful contra-rotating engines. The NK-110, which was tested in the late 1980s, had a contra-rotating propeller configuration with four blades in front and four in back, like the NK-12. Its {{convert|4.7|m|in|order=flip|abbr=off|adj=mid|propeller diameter}} was smaller than the NK-12's {{cvt|5.6|–|6.2|m|in|order=flip}} diameter, but it produced a power output of {{cvt|15665|kW|hp|order=flip}}, delivering a takeoff thrust of {{convert|177|kN|lbf|order=flip|abbr=off}}.<ref name="NK110Sheet">{{cite web |language=ru |page=48 |title=NK-110 |url=http://www.uvauga-dvig.narod.ru/nk-110.pdf |website=Ulyanovsk Higher Aviation School of Civil Aviation}}</ref> Even more powerful was the NK-62, which was in development throughout most of the decade. The NK-62 had an identical propeller diameter and blade configuration to the NK-110, but it offered a higher takeoff thrust of {{cvt|245|kN|lbf|order=flip}}. The associated NK-62M had a takeoff thrust of {{cvt|285.2|kN|lbf|order=flip}}, and it could deliver {{cvt|314.7|kN|lbf|order=flip}} of emergency thrust.<ref name="NKLargeThrust">{{cite magazine |language=ru |year=2018 |number=1 |volume=115 |pages=20–24 |given=V. A. |surname=Zrelov |title=Development of engines 'NK' large thrust on the basis of a single gas generator |magazine=Dvigatel |url=http://engine.aviaport.ru/issues/115/pics/pg20.pdf}}</ref> Unlike the NK-12, however, these later engines were not adopted by any of the aircraft design bureaus.

In 1994, Antonov produced the [[Antonov An-70|An-70]], a heavy transport aircraft. It is powered by four [[Progress D-27]] [[propfan]] engines driving contra-rotating propellers. The characteristics of the D-27 engine and its propeller make it a propfan, a hybrid between a turbofan engine and a turboprop engine.