russian soviet fighter designed late 1920s entered service retired advent fighters higher performance design development development began investigations loss completed new shared characteristics earlier design including layout wings new design designed russian supervision head designer department debate proper powerplant new fighter rejected wright tornado radial engine decided favor liquid cooled engine wooden mock completed april formal approval design come june static tests sized model began october time negotiations license engine finished oval section semi fuselage covered birch small fuselage engine enclosed metal wings covered fabric clark profile internal wires fitted reinforce wings control surfaces framed covered fabric provided differential type type separated wings attached upper wing fuselage profile reinforced steel wires conventional fixed rubber shock main gear replaced like fitted engine semi retractable extended fuselage rear main gear fuel tanks fitted main fuselage small imp gal gal tank mainly start engine center section upper wing engine tank total fuel carried initially fitted fixed synchronized vickers machine guns later replaced machine guns central optical provided ring sight offset starboard aircraft bomb racks carry bombs prototype completed early flight february manufacturer trials finished march state acceptance trials april pilots russian air force scientific test institute criticized lack directional stability high speeds slight problem control response maneuvers area vertical tail increased elevators given horn alleviate problem split addressed second problem production begun aircraft actually approved service use aircraft completed smaller second prototype completed august tested different propeller high speed increased speed mph lengthened run aircraft completed plus prototypes imported engines remainder license built approximately built gordon citing sources state provide yearly production table lists built add prototypes included operational use initial deliveries units replaced equipped 4th 7th squadrons russian air squadron later fighter squadrons russian 13th later 7th fighter squadrons 17th 19th squadrons later units based ukraine began receive theirs following year equipped later air detachment later 33rd fighter squadron delivered 1st 2nd october service year later hand january fell year later end relegated secondary roles newer powerful fighters entered service notably variants russian enlarged seat variant extra frame added fuselage extended wingspan enlarged rudder machine guns mounted ring observer cockpit prototype completed early flight year prototype crashed failure dive later killing pilot operators soviet_union soviet air_force specifications data general characteristics crew length wingspan height wing area clark weight loaded weight powerplant engine performance maximum speed mph range nmi service ceiling wing loading power mass time altitude min horizontal turn time sec armament machine guns
Polikarpov I-3