Editing Yakovlev Yak-4

{{Short description|Soviet light bomber during WWII (1941–1945)}}
{{Infobox aircraft
  |name =Yak-4
  |image =Yakovlev_Yak-4_-_IV.jpg
  |caption =
  |type =[[Light bomber]]
  |manufacturer =[[Yakovlev]]
  |designer =[[Alexander Sergeyevich Yakovlev]]
  |first_flight =20 February 1940
  |introduction =1941
  |retired =1945
  |status =
  |primary_user =[[Soviet Air Forces|VVS]]
  |more_users =
  |developed_from =[[Yakovlev Yak-2]]
  |number_built =90
  |unit cost =
  |variants =
}}

The '''Yakovlev Yak-4''' (Service names '''Yak-4''', '''BB-22bis''' (''Blizhnij Bombardirovschik'', russian ''ближний бомбардировщик'', "short-range bomber")) was a [[Soviet Union|Soviet]] [[light bomber]] used during [[World War II]]. It was developed from the Ya-22/[[Yakovlev Yak-2|Yak-2]].

==Design and development==
[[File:Yak-4, light bomber plane.jpg|thumb|left|Yak-4]]
The Yak-4 was an improved version of the Yak-2 with more powerful [[Klimov M-105]] engines and a number of other changes that were made to try to rectify the problems of the Yak-2. Two additional fuel tanks were added in the outer wings to bring the total capacity up to {{convert|180|L}} and the gunner's canopy was bulged to give him more room to use his {{convert|7.62|mm|abbr=on}} [[ShKAS machine gun]]. The upper fuselage was redesigned to improve the gunner's field of fire and the oil coolers were relocated from the sides of the engine nacelles to the 'chin' position to improve their performance.

==Operators==
;{{USSR}}
*[[Soviet Air Forces|VVS]]

==Specifications (Yak-4)==
[[File:Yakolev Yak-2 3-view.svg|thumb|Yak-4]]
{{Aircraft specs
|ref=The Osprey Encyclopaedia of Russian Aircraft 1875–1995<ref name=osprey>{{cite book | last=Gunston |first=Bill |title=The Osprey Encyclopedia of Russian Aircraft 1875–1995 |year=1995 |publisher=Osprey |location=London |isbn=1-85532-405-9}}</ref>
|prime units?=met
<!--
        General characteristics
-->
|crew=2
|length m=10.18
|length note=
|span m=14
|span note=
|height m=
|height note=
|wing area sqm=29.4
|wing area note=
|aspect ratio=<!-- sailplanes -->
|airfoil=Göttingen 387<ref name="Selig">{{cite web |last1=Lednicer |first1=David |title=The Incomplete Guide to Airfoil Usage |url=https://m-selig.ae.illinois.edu/ads/aircraft.html |website=m-selig.ae.illinois.edu |access-date=16 April 2019}}</ref>
|empty weight kg=4560
|empty weight note=
|gross weight kg=6115
|gross weight note=
|max takeoff weight kg=
|max takeoff weight note=
|fuel capacity=
|more general=
<!--
        Powerplant
-->
|eng1 number=2
|eng1 name=[[Klimov M-105]] 
|eng1 type=V-12 liquid-cooled piston engines
|eng1 kw=821
|eng1 note=

|prop blade number=3
|prop name=constant-speed propellers
|prop dia m=<!-- propeller aircraft -->
|prop dia note=
<!--
        Performance
-->
|max speed kmh=533
|max speed note=
|max speed mach=<!-- supersonic aircraft -->
|cruise speed kmh=
|cruise speed note=
|stall speed kmh=
|stall speed note=
|never exceed speed kmh=
|never exceed speed note=
|minimum control speed kmh=
|minimum control speed note=
|range km=925
|range note=
|combat range km=
|combat range note=
|ferry range km=
|ferry range note=
|endurance=<!-- if range unknown -->
|ceiling m=9700
|ceiling note=
|g limits=<!-- aerobatic -->
|roll rate=<!-- aerobatic -->
|climb rate ms=
|climb rate note=
|time to altitude=
|wing loading kg/m2=
|wing loading note=
|disk loading kg/m2=
|disk loading note=
|fuel consumption kg/km=
|power/mass=
|thrust/weight=
|more performance=<!--<br />
*'''Take-off run:''' {{cvt||m|0}}
*'''Take-off run to {{cvt|15|m|0}}:''' {{cvt||m|0}}
*'''Landing run:''' {{cvt||m|0}}
*'''Landing run from {{cvt|15|m|0}}:''' {{cvt||m|0}}-->
<!--
        Armament
-->
|armament=
* 2 × 7.62&nbsp;mm [[ShKAS machine gun]]s
* up to {{convert|600|kg|abbr=on}} of bombs

|avionics=
}}

==References==
{{reflist}}
{{more footnotes|date=March 2016}}

===Further reading===
* {{cite book |last1=Gordon |first1=Yefim |title=Soviet air power in World War 2 |date=2008 |publisher=Midland |location=Hinkley |isbn=978-1-85780-304-4}}

==External links==
{{commons category|Yakovlev Yak-4}}
* [https://web.archive.org/web/20130430162446/http://www.aviation.ru/Yak/#4 Yak-4 description on aviation.ru]

{{Yakovlev aircraft}}
{{Soviet bomber-attack designations}}
{{WWIIUSSRAF}}

[[Category:Yakovlev aircraft|Yak-004]]
[[Category:1940s Soviet bomber aircraft]]
[[Category:Aircraft first flown in 1940]]
[[Category:Twin piston-engined tractor aircraft]]
[[Category:Aircraft with retractable conventional landing gear]]