In parallel with the I-26 (or Y-26), the Yakovlev design bureau developed a two seat version under the designation Y-27. One pre-production I-26 was completed to this configuration. It was intended to not only serve as a dual control fighter trainer but also as a liason and unit support aircraft. Compared with the I-26, the Ya-27 was simplified and reduced in weight, the tandem cockpits being enclosed by an extended glazed canopy. The resulting Yak-7 aircraft entered production in May 1941 and was soon found to have better flying qualities than that of the series Yak-1 aircraft. This performance, combined with the urgent need for for more fighters, led to production of a single seat version of which the first was flown in June 1941. In the following month the fighter was officially designated the Yak-7A and the two seater Yak-7V. By the end of 1941, a new single seater, the Yak-7B had replaced the Yak-7A. Total delivery of all versions of the Yak-7 was 6,399 aircraft with production ending in early 1943. Of this number, some 1,500 were Yakovlev Yak-7Vs.

Yak-7A

series version of a single seat fighter with the 1,050 hp (783 kw) M-105P engine. The rear cockpit was deleted and faired over and a new pointed wing with a span of 33 ft 7 3/4 in (10.00 m) was introduced.

Yak-7V

Definitive designation for the two seater which by July 1941 was in large scale production with the same wingspan as the Yak-7A. Some Yak-7Vs had fixed landing gear that could operate with wheels or skis.

Yak-7B

Wingspan was reduced to 32 ft 9 3/4 in (10.00 m) but still the same wing area as the Yak-7A and Yak-7V. Landing gear was simplified and equipment was improved. This version proved to be a very important type in the V-VS inventory that performed well against enemy fighters. Over 5,000 of this type were produced.

Yak-7D

Experimental version with wooden wings and metal spars and increased fuel capacity.

Yak-7/M-82

A version with a redesigned fuselage to mount the M-82 radial engine and armed with one fuselage mounted 12.7 mm (0.50 in) UBS machine gun and two 20 mm ShVAK cannon. Was tested in 1941.

Yak-7T

Two aircraft tested with engine mounted heavy cannon for anti-tank duties. One had the 37 mm NS-37 cannon and the other the 45 mm NS-45 cannon.

Yak-7K

A field conversion of 1944 for use as a VIP transport with a very comfortable rear cockpit. Several examples were modified to this version.

Yak-7PVRD

Two series aircraft tested with two DM-4C ramjets on pylons under wings. Maximum speed was increased by 56 mph (90 km/h).

Specifications (Yakovlev Yak-7A)

Type: Two Seat Tandem Trainer & Liason

Design: Aleksandr Sergeyevich Yakolev

Manufacturer: State Industries

Powerplant: One 1,050 hp (783 kw) M-105P 12-cylinder Vee engine.

Performance: Maximum speed 407 mph (655 km/h) at 10,170 ft (3100 m); service ceiling 35,105 ft (10700 m).

Range: 559 miles (900 km) on internal fuel.

Weight: Empty equipped 4,641 lbs (2105 kg) with a maximum take-off weight of 5,864 lbs (2660 kg).

Dimensions: Span 33 ft 7 1/2 in (10.25 m); length 27 ft 10 1/4 in (8.49 m); height 7 ft 11 1/4 in (2.42 m); wing area 159.53 sq ft
(14.83 sq m).

Armament: One engine mounted 20 mm ShVAK cannon with 140 rounds and two synchronised 12.7 mm (0.50 in) UBS machine guns with 348 rounds each.

Variants: Ya-27 (prototype), Yak-7 (initial designation for the two seat liason/trainer and also for the first single seat conversion), Yak-7A, Yak-7V (official designation for the two seat trainer), Yak-7B (shorter winspan of (10.00 m) 32 ft 9 3/4 in), Yak-7D (experimental) Yak-7/M-82 (M-82 radial engine), Yak-7T (anti-tank), Yak-7K (VIP transport), Yak-7PVRD (ramjets under wings).