II. Force structure on the eve of the war:

The Soviet V-VS force structure on the West at the eve of Barbarossa is well known. The hypothetical mid-May 1942 structure is then closely patterned on data at hands. VVS forces in the West were deployed in 5 military districts, Leningrad, Baltic-special, Western-special, Kiev-special, Odessa.
By May 1942 however, the V-VS would have been organized around "Air Armies" (probably one for each Military District), composed of independent Regiments and Air Divisions (AD) each composed of 3 to 4 Regiments (Polki) with 40 planes.
Total fighter regiments (IAP): 57 (for 19 IAD) including 800 Mig-3/3D, 1,480 Yak-1 and LaGG-3.
Total bomber regiments (BAP): 48 (for 16 BAD) including 1000 Pe-2, 40 Tu-2, and 880 older Il-4/DB3F.
Total ground attack regiments (ShAP): 24 (for 8 ShAD each with 2 "heavy" regiments flying on Il-2 and one "light" regiment flying on Polikapov I-153Sh) with 640 Il-2 and 320 I-153Sh.
Total reconnaissance regiments: (RAP): 8 with 100 Pe-2, 100 Mig-3, 40 Yak-4, 80 SB-2bis.

TOTAL: 5480 planes of which 4240 "modern".
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Force distribution:

Leningrad VO
7th Air Army, Col. Gen. I.M. Sokolov with 880 planes and:
239, 240, 258, 259 IAD (480 fighters)
242, 261 BAD (240 bombers)
260 ShAD (120 assault planes)
2 separate RAP (80 reconnaissance planes)

Baltic-special VO
3rd Air Army, Maj. Gen. M.M. Gromov with 880 planes and:
209, 210, 256 IAD (360 fighters)
210, 211 and 270 BAD (360 bombers)
212 ShAD (120 assault planes)
1 separate RAP (40 reconnaissance planes)

Western-special VO
1st Air Army , Maj. Gen. T.F. Kutsevalov, with 1,160 planes and:
201, 202, 234 and 235 IAD (480 fighters)
213, 214, 215 BAD (360 bombers)
231, 232 ShAD (240 assault planes)
2 separate RAP (80 reconnaissance planes)

Kiev-special VO
2nd Air Army, Maj. Gen. S.A. Krasovskiy, with 1,200 planes and:
205, 206, 207, 236 and 237 IAD (520 fighters)
208, 222 and 223 BAD (360 bombers)
225 and 226 ShAD (240 assault planes)
2 separate RAP (80 reconnaissance planes)

Odessa VO:
4th Air Army, Maj. Gen. K.A. Vershinin, with 1,000 planes and:
216, 217 and 229 IAD (360 fighters)
132, 218 and 229 BAD (360 bombers)
230 and 238 ShAD (240 assault planes)
1 separate RAP (40 reconnaissance planes).
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V-VS WESTERN SOVIET UNION RESERVE

(1) The Soviet High Command (STAVKA) would have most certainly created a strategic reserve around Moscow. This could have been a special Air Army:
6th Air Army, Maj. Gen. Stepanov, with 880 planes and
220, 283 and 284 IAD (360 fighters)
221, 262 BAD (240 bombers)
228, 291 ShAD (240 assault planes)
1 separate RAP (40 reconnaissance planes).

(2) A special force of Long-Range aviation (ADD) would have been formed under direct STAVKA command and would have been made of 320 bombers mixing Pe-8, Yer-2 and DB-3F.
Commander: Lt. Gen. A Ye. Golovanov.
One special Heavy Bomber Air Division (probably called 80 TBAD) where heavy Pe-8 bombers would have been allocated to 2 regiments (80 planes) supplemented by 2 others flying on DB3F.
81 BAD (with 4 regiments).

(3) The North-Caucasus military district would have played the role of a strategic reserve for the Western front once Soviet authorities convinced that British-French forces were not to attack them in Baku.

5th Air Army, Col. Gen. S.K. Goryunov, with 880 planes and:
265, 268 & 269 IAD (360 fighters),
238, 271, 272 BAD (360 bombers)
243 ShAD (120 assault planes)
1 separate RAP (40 reconnaissance planes)

By combining the 6th and the 5th Air Armies and the ADD, STAVKA would have had 2,080 planes (of which probably at least 1300 "modern") as a strategic reserve. Probably up to 1,800 could have been used against Axis forces.

IA-PVO:
The IA-PVO was tasked with defence of area of strategic relevance. This command was organized around Interceptor Air Corps (IAK) each with 5 to 6 regiments of 40 planes. However a large part of PVO units would have been deployed around the Caspian in the Transcaucasus VO to protect Baku oilfields at least till winter 41/42. It is possible that improvements in Soviet to GB/France relations by March/April 42 could have allowed some of these units to be re-deployed to the West.

40 IA-PVO fighter regiments (or seven IAK) would have been deployed in Western military districts, with 1,520 MiG-3/3D and 80 Pe-3, or a total of 1600, all "modern" types.
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Repartition

Leningrad VO or Northern PVO zone: two IAK (400 planes)
Baltic-Special or Northwestern PVO zone: one IAK (240 planes)
Western PVO zone: one IAK (240 planes)
Kiev PVO zone: one IAK (240 planes)
Odessa or Southern PVO Zone: one IAK (240 planes)

Reserve: Moscow with one IAK (the 6th IAK).
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Naval aviation (VVS-VMF)
1,445 planes were deployed by the Northern, Baltic and Black Sea Fleets by June 1941 on a total of 2,824 planes in VMF inventory.
Of these 1,445 planes, 650 would have been fighters, 220 bombers (with 40 Pe-8, 40 Pe-2, 140 DB3), 150 torpedo-bombers (all Il-4/DB-3F) and the rest older types and flying boats.

By Mid-May 1942 one could expect that 1860 planes would have been deployed in the 3 "Western" Fleets, with 800 fighters (360 Mig-3, 240 Yak-1, 200 LaGG-3), 720 bombers and torpedo-bombers (40 Pe-8 and 80 Yak-1SB parasite dive-bombers, 120 Pe-2, 480 DB-3F), 100 reconnaissance planes and 240 flying boats.
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repartition:

Northern Fleet (220): 80 fighters, 80 bombers and torpedo-bombers, 20 reconnaissance and 40 flying boats.
Baltic Fleet (840): 360 fighters, 360 bombers and torpedo-bombers, 40 reconnaissance and 80 flying boats.
Black Sea Fleet (800): 360 fighters, 280 bombers and torpedo-bombers, 40 reconnaissance, and 120 flying boats.
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