General Information
Type Yak-1 improved
Function Series Fighter with modifications
Year 1942 1943
Crew 1
Type VK-105PF
Power at ...
Length 8.48m
Height ?m
Wingspan 10.0m
Wing area 17.25m2
Weights and loads
Empty (kg) 23952316
Loaded (kg) 29002884
Wing Load (kg/m2) 168167
Power load (kg/hp) 2.402.40
Speed (km/h)
at 0m 523531
at 3850m 590n/a
at 4100m n/a592
Landing 140137
Turn time (sec) 1819
Roll (m)
Landing 500560
Takeoff 320340
Range (km)
Practical 650700
Ceiling (m)
Ceiling 1000010050
to 5000m 5.6min5.4min
during combat turn 900m1150m
Fuel 305kg
Gun Type 1*20mm ShVAK
Position Through the hub
Ammo 120
Gun Type 1*12.7mm UBS
Position Engine cowling
Ammo 200
Salvo 1.997 (kg/sec)
Bombs see Yak-1 with bombs
Rockets see Yak-1 with rockets

Yak-1 variants with improved airdynamics (1942 and 1943), A.S.Yakovlev

(18k b/w) A 1943 'Standard' Yak-1, one of the last of its type. "Soviet Combat Aircraft of the Second World War" by Yefim Gordon and Dmitri Khazanov, Vol.1 p.130
Courtesy of Thomas Heinz

Efforts of the A.S.Yakovlev OKB aimed on the Yak-1 airdynamic refinement continued through all the production period. Normally, this work was performed on the team initiative and gradually introduced on the production lines.

But few cases really stay out of those regular efforts.

During Summer and Fall of the 1942 during Stalingrad Battle air combat situation for Soviet Army worsened: Luftwaffe put into action new Bf-109F-4 and Bf-109G-2 with more powerful engines. Those Messerschmitts had substantial advantage over series Yaks in climb and maneuverability and some in speed (specially when 3min boost system was engaged).

Following major efforts were undertaken by A.S.Yakovlev OKB:

The GKO order was to increase aircraft speed by 20km/h: 525km/h at ground level and 590km/h at 3750m. Research centers TsAGI and LII recommended, and designers introduced following measures:

In October 1942 series built Yak-1 N°16-99 was flown before and after airdynamic improvements. Trials took place at LII by test-pilot V.N.Kochenuk (from Factory N°292) and engineer V.Ya.Molchanov (LII). Results were positive - performance of improved Yak matched demands of VVS.

As a part of research program influence of different factors on the aircraft speed were studied:

Production lines quickly adopted required changes in construction. One year later (October-September 1943) another series built Yak-1 N°23-148 was taken through same procedure: flight test program, refinement of the plane, and another flight test. This time only minor gain was achieved in aircraft speed (~5km/h), proving that aircraft manufacturers used all reserves of the Yak-1 improvement. Technological process finally reached its perfection. Speed variation among series Yaks also was within +/-5km/h interval.

'Clean' series Yak-1 was superior to the Bf-109G-2 in all respects up to 5000m. On higher altitudes 'Messer' gained speed advantage (up to 96km/h at 7000m). This advantage was not that crucial - Yak's maneuverability and handling remained superior up to 8000m, and high altitude air combat was not typical for the East Front.

Improvements discussed here were introduced in mass production starting from 111th batch (December 1942) until the last 192th batch that rolled out in July 1944, totaling 4461 aircraft.


  • "Yak fighters of the Great Patriotic War period" by A.T .Stepanets
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  • Created July 29, 2000 Back to
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