FMP - Anti-aircraft Weapons 1939

AAMGs and Light AA Guns

In 1939 Finnish Air Defence was very weak. New twin anti-aircraft machine gun model 7.62 mm ItKk/31 intended for the close defence of troops was although under production which continued until the end of the war with improved model 7.62 mm ItKk/31-40 but the total number of these weapons was rather low. During the Winter War Light AAMG Platoons and Companies were equipped with these weapons. Also many anti-aircraft batteries had these for close-defence. During the Continuation War light AAMGs were additionally issued to artilllery and Air Force units.

A notable amount of new modern 20 mm ItK/30 light AA cannons had been ordered from Germany before the war but only about 100 pcs had arrived in Finland before the deliveries ended because of the Winter War. Heavy AAMG Companies were equipped mainly with these guns. Light 20 mm guns were also bought from Italy (Breda) and for the Navy from Denmark (Madsen). Late in 1942 a new more effective Finnish 20 mm ItK/40 light twin AA cannon designed by A. Lahti finally entered service. It had light but too weak carriage.

The most important light anti-aircraft gun model during the Winter and Continuation War was Swedish 40 mm Bofors m/38 (40 ItK/38) which was also licence-made in Finland by State Gun Factory (VTT). In the late summer 1944 the deliveries of 37 mm German AA guns were about to began to replace the losses of Bofors guns but only first batch of four second hand pieces arrived in Finland by the end of the Continuation War.
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Heavy AA Guns

There were only a few heavy 75 or 76 mm AA batteries in 1939 and their guns were largely obsolescent and fixed. Heavy guns were urgently obtained from Great Britain and Italy and since late 1940 also from Germany. During the Continuation War in 1941 Finnish troops captured a large number of heavy Soviet AA guns. In 1943 and 1944 a considerable quantity of German 88 mm ItK/37, Soviet-made 76 mm ItK/31 ss and re-worked Soviet-made 88 mm ItK/39 ss (originally 85 mm) heavy AA guns were bought from Germany to strengthen the anti-aircraft defence of the largest cities in Finland and also for the coastal defence.

In November 1942 modified heavy anti-aircraft shells for Skoda and Bofors guns were tested in Finland. "Electron metal" was added to shells which were designed to flash stronger than normally used ones to imitate explosions of much heavier calibre guns and hits closer to planes. The idea was to bluff enemy pilots to drop their bombs away too early especially at night and escape immediately to avoid direct hits. Evaluation was succesful and shells for other gun models were also re-worked.
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Battery Computers, Range-Finders, Searchlights and Audible Direction-Finders

In 1939 there were a total of ten battery computers (one m/29 Berkog, and nine m/34 Vickers: 2x "Va", 3x "Vb", 4x "Vc"), eighteen two to four meter range-finders (8x 2 m, 7x 3,5 m and 3x 4 m), 31 searchlights and five audible direction-finders in Finland.

Computers used in heavy AA batteries were largely obsolete or worthless during the Winter War. Therefore many heavy batteries used simple 3-T firing method developed by Lt.Gen. P. Nenonen. It was a development of the WW I calculating methods: firing values were calculated mean values of several estimates. Method was too slow against any faster aircraft but all heavy batteries used it used as back-up. New more advanced computers were bought from Germany soon after the Winter War but equipment stayed very heterogeneous until the end of the WW II.

Light AA batteries used lighter range-finders for measuring distance between target and guns. During the war a total of 32 different models were in use in Finland and their base widths varied from 0.6 to 4 m. A typical small one was German-made 1.25 m range-finder Hahn-Cassel which had been used already during the WW I and was obsolete by WW II. Stereo range-finders like the British 3.5 m range-finder Barr & Stroud were although better suited for AA batteries.

There were also too few searchlights in 1939. After the Winter War and during the Continuation War a lot more anti-aircraft equipment was obtained both from Germany and Finland. Searchlights were either designed for searching targets or to follow a certain target. Audible direction-finders were used in conjuction with searchlights and belonged to searchlight batteries but their meaning was quite minimal because their accuracy proved to be too weak. New radars bought in 1943 from Germany were much more accurate but their number remained low.

Designation Calibre [mm] Type/Model Year .	Effective Range [m]	Rate of Fire [rds/sec]	Number [pcs 39/ (40)/41/44]	Country of Origin	Notes
Anti-Aircraft Machine Guns (AAMG) / Ilmatorjuntakonekiväärit (It.Kk.) .
7.62 ItKk/09 7.62 ItKk/31, 7.62 ItKk/31-40 7.62 ItKk/33-39 . 7.62 ItKk/09-31 8.00 ItKk/36 .	<1.000 1.000 . 1.000 . <1.000 1.000	7,5/15 30 . 15,5 . 30 ?	? 80/135/ 475 -/-/130 . -/80/? (?)/-/-	Rus, Fin Fin . Fin . SU Swe	Ordinary Maxim MG, part with AA mount. Twin AAMG, 135 made by 1940, improved version made 1940-44. AA version of Lahti L-33 observer MG, mainly used by Navy on small craft. In-line quad AAMG, war booty 1939 - 1942. Twin AAMGs of Swedish SFK in 1940.
Anti-Aircraft Rifles / Ilmatorjuntakiväärit (It.Kiv.) .
Lahti L-39/44 (20 ItKiv/39-44) .	1.200	5	-/-/300	Fin	20 mm full-automatic version of L-39 AT rifle.
Light Anti-Aircraft Guns / [Kevyet] Ilmatorjuntakanuunat (It.K) .
20 ItK/23 20 ItK/39 M . 20 ItK/30 BSW . 20 ItK/38K . 20 ItK/35 20 ItK/40 . 40/40 V15 40/40 V34 40 ItK/35 B 40 ItK/36 B 40 ItK/36 BK 40 ItK/36 BK2 40 ItK/38 B 40 ItK/38 BK 40 ItK/39 B .	1.000 1.200 . 1.200 . 1.200 . 1.200 1.200 . 1.500 2.500	2,5 6,6 . 4,6 . 7,5 . 4 23 . 3,3 3,7 2 2 2 4 2 2 2	4/4/4 (50)/150/ 200 30/132/ 172 -/-/53 . -/88/83 -/-/170 . 9/9/6 8/8/8 64/210/290	Sui Den . Ger . Ger . Ita Fin . UK/Ita UK Swe, Pol Swe, Hun Swe Swe Fin Fin Swe	Semag-Oerlikon, bought for trials in 1924. Madsen automatic gun, used mainly on ships in 1939-44. Gustloff-Werke and Berliner Suhlen Werke (BSW). Gustloff-Werke and BSW, K = fixed model. Breda. 48 pcs delivered between 2.-3.1940. Twin gun made by State Rifle Factory (VKT) mainly in 1943-44. Vickers-Armstrong / Terni 2 pdr "Pom-Pom", used on ships. Bofors, MAVAG, used also in ships, K = fixed twin guns of Väinämoinen and Ilmarinen, State Gun Factory (VTT), K = fixed/static, special model used in trains.
Designation Calibre [mm] Type/Model Year .	Range [km]	Rate of Fire [rds/min]	Number [pcs 39/ (40)/41/44]	Country of Origin	Notes
Heavy Anti-Aircraft Guns / [Raskaat] Ilmatorjuntakanuunat (It.K) .
75 ItK/97-14 PK . 75 ItK/30 B . 75 ItK/37 . 76 ItK/14 76 ItK/02-34 76 ItK/16 . 76 ItK/16 Br, 76 ItK/16-35 Brk 76 ItK/27K 76 ItK/28 76 ItK/29 76 ItK/31 ss 76 ItK/31-40 . . 76 ItK/34 V 88 ItK/37 RMB 88 ItK/37K 88 ItK/39 ss . . .	? . 5 . 4-6 . 5 5 4 . ? . 5 . . ? . . . ? 6 . ?	? . ? . 12 . 12 4-5 5-6 . ? . 12 . . 12 . . . ? 12 . 12	-/24/24 . -/9/9 . -/20/20 . 2/-/- 8/8/8 -/24/24 . -/12/12 . 8/8/8 4/4/4 4/4/4 -/-/115 = . . 12/12/12 -/-/18 -/-/72 -/-/18	Fra/Ger . Swe . Cze/Ger . Rus Rus/Fin UK . Ita . Swe . . SU/Ger . . . UK Ger . SU/Ger	Puteaux, bought from Germany in 1940 for coastal AA batteries, K = fixed. Bofors, arrived in February 1940 for the defence of the city of Turku. Skoda, second-hand guns bought from Germany in 1940. Putilov "Zenit", originally naval guns. Obuhov "Zenit", originally naval guns. Vickers-Armstrong, donated from UK in 1940. Breda, arrived in 1940. . Bofors, K = fixed/static. . . Fixed or with two-wheel carriage; with four-wheel ZU-8 carriage, war booty of 1941, 72 bought from Germany in 1944 for coastal AA batteries. Vickers-Armstrong, bought in 1936. Rheinmetal-Borsig, bought in spring 1943 K = fixed, bought in the summer 1944. Former Soviet 85 mm, reworked in Germany to 88 mm, bought in 1944, ss = sotasaalis [war booty].
Designation Model Year Name . .	Range distance / altitude [km]	Max Target Speed [m/s]	Max Dist. from the Guns [m]	Country of Origin	Notes
Battery Central Computers (Anti-Aircraft Gun Directors) / Keskuslaskimet .
m/29 Berkog . m/30 Äldre . m/34 Vickers . . m/34 Gala-Borletti m/35 Delta . m/36 Gamma-Juhasz . m/37 Skoda T7n, Puaso 3 m/35 Puaso-Aufiere and m/44 Puaso-Aufiere m/40 Lambda . . .	?/? . ?/? . ?/7 . . ?/? 1.2-12 . 0.9-10/ 0.1-8 1-12/ 0-9.6 12.7/8 . . 1.2-18/ 0-12	180 . ? . ? . . ? 150 . I, II 166 III 260 140 . 200 . . 300	500 . ? . ? . . ? ? . 500 . 600 2000 200 . . 500	Ned . Swe . UK . . Ita Ger . Hun/Fin . Cze/Ger SU/Ger SU/Fra/ Ger . Ger	Zeiss Holland, with range-finder, one was used at Viborg during the Winter War only. Three computers came in spring 1940, with 75 ItK/30 B guns. Three sub-models: "Va" for 76 ItK/28, "Vb" for 76 ItK/27, "Vc" for 76 ItK/34, the best computer used in the Winter War. Three bought with Breda guns, worthless. With 88 ItK/37. . Licence-made in Finland by Strömberg, three sub-models: I, II and improved III. With Skoda guns, improved Soviet copies were bought from Germany. German-made combination of French and Soviet computers, for 76 ItK/31; improved m/44 for 88 ItK/39 ss. Three were bought in spring 1943 for 88 ItK/37 RMB, the best computer used in WW II, actually a full fire control device.
Note: there was a spelling mistake in the names of the Finnish Puaso models. Correct spelling should have been Puazo. .
Designation Model Year .	Diameter [cm]	Range [m]	Type	Country of Origin	Notes
Searchlights / Valonheittimet .
m/32 SIA m/35 SIA m/37 . MUG-62 Strömberg m/41 Strömberg m/42 AEG . .	150 90 110 . 62 210 150	10.000 8.000 6.000 . ? 15.000 12.000	Search Follow Follow . ? Search Search	Swe Swe Fin . Fin Fin Ger	Svenska Instrument Ab. Svenska Instrument Ab. Valonheitinkorjaamo [Searchlight Repair Shop]. Strömberg Oy [Ltd]. 69 pcs produced by Strömberg Oy. Allgemeine Elekricitäts Gesellschaft, 180 pcs bought during the war.
Designation Model Year .	Range [km]			Country of Origin	Notes
Audible Direction Finders / Kuulosuuntimet .
m/39 Goerz m/40 Tepas m/42 [ET-2] m/42 RHI m/43 Strömberg .	? ? ? ? ?			Aut/Ger Bel SU Ger Ita/Fin	Also for route determination. . War booty. Bought together with AEG searchlights. Licence-made in Finland by Strömberg Oy.