The insignia visible on rear the turret of Archer.
“Lidice”, 1st Czechoslovak Tank Brigade emblem :
This decal is available in game. The condition to get it is : Defeat 585 players while controlling Russian tank.
T-34/76 Mod.43 of 1st Czechoslovak Tank Brigade, September 1943, Novokhopensk.
Source : [Article Series] Weapons of Victory: T-34 "Lidice" - News - War Thunder
“Laughing Swordfish” emblem of the U-96 (Type VIIC) - 7.Unterseebootsflottille :
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U-96 (Type VIIC), Saint-Nazaire, February 1941
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U-96 (Type VIIC), France, May 1941
This decal is available in game. The condition to get it is : Make 1500 points for both factions during the « Battle of the Atlantic - Ships Against Submarines » event.
Source : [Event] Battle of the Atlantic: Ships Against Submarines! - News - War Thunder
“ Rat” emblem of the U-60 (Type II C) - 1.Unterseebootsflottille :
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U-60 (Type II C), Atlantic, circa 1940
This decal is available in game. The condition to get it is : Make 1500 points for both factions during the « Battle of the Atlantic - Ships Against Submarines » event.
Source : [Event] Battle of the Atlantic: Ships Against Submarines! - News - War Thunder
“Red Devil” emblem of the 91. jaktflygdivisionen (Ivar Röd) - Swedish Air Force :
On J 21 (Ingame) :
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On J 22 (Ingame) :
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On J 29 (Ingame) :
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This decal was available during the period between the 23th November to the 23th December 2022. The condition to get it was : Defeat 40 players (20 in RB and SB) while controlling Swedish aircraft, or purchase for 200 GE.
Source : [Decals] New authentic decals (available until December 23rd) - News - War Thunder
Pictures and research published on the Old Forum by Thiky
“Totenhand“ emblem of the Stab./Sturzkampfgeschwader 77 :
On Junkers Ju-88 A-4 (Ingame) :
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On Messerschmitt Bf-110 F2 (Ingame) :
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This decal was available during the period between the 23th November to the 23th December 2022. The condition to get it was : Defeat 50 players on ground vehicles (25 in RB and SB) while controlling German aircraft, or purchase for 200 GE.
Source : [Decals] New authentic decals (available until December 23rd) - News - War Thunder
Credits : FalkeEins - the Luftwaffe blog: Stabsstaffel. StG 77 'Death's hand' emblem on Bf 110 and Ju 88
Emblem of the XVI Gruppo “Cucaracha” - Aviazione Legionaria in Spain :
On CR. 32 (Ingame) :
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This decal was available during the period between the 23th November to the 23th December 2022. The condition to get it was : Score 2,000 points in 5 battles while controlling Italian aircraft, or purchase for 200 GE.
Source : [Decals] New authentic decals (available until December 23rd) - News - War Thunder
Emblem of the No. 63 Squadron - Royal Air Force :
On Hawker Hunter F.6 (Ingame) :
This decal was available during the period between the 23th November to the 23th December 2022. The condition to get it was : Defeat 40 players (20 in RB and SB) while controlling British aircraft, or purchase for 200 GE.
Source : [Decals] New authentic decals (available until December 23rd) - News - War Thunder
Emblem of the 90th guards tank division - Russian Federation :
On T-72B3 (In game) :
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This decal was available during the period between the 23th November to the 23th December 2022. The condition to get it was : Score 1st-3rd place in 7 battles while controlling Soviet ground vehicles, or purchase for 200 GE.
Source : [Decals] New authentic decals (available until December 23rd) - News - War Thunder
Two another example to this insignia from the 370ª Squadriglia
on MC200
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and on MC202
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“To the pilot of the Stalingrad Front ” decal USSR:
On a Yak-1B (in game):
“Eremin’s aerial victories ” decal - USSR:
On a Yak-3 (in game):
These decals were unlockable during the event Legend of Victory: Eremin’s Yak-3 May 8th until May 20th, 2024 for 35k mission points in air battles or purchasing the specific stages for 699(?)GE.
Source: [Event] Legend of Victory: Eremin’s Yak-3! - News - War Thunder
Emblem of the Patrol Squadron 50 - U.S. Navy :
On PBM-5S Mariner (not ingame), under the cockpit :
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U.S. Navy PBM-5S Mariner of Patrol Squadron 50 (VP-50) in flight, April 1956
This decal is available for free by reaching Level 3 on Battle Pass: Season XVI, “Skilled Marksman”.
Source : [Event] [BattlePass] Meet Skilled Marksman, the 16th Season of the Battle Pass! - News - War Thunder
Groupe II/23 GUYENNE / Squadron 346 emblem - Free French Air Force :
On Handley Page “Halifax” Mk.III (In game) :
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This decal was available during the period between the 23th October 2024 to the 21th January 2024. The condition to get it was : reaching Level 22 of the the Battle Pass : “Guided Fury” - Season XVII
Source : [Event] [BattlePass] Meet Guided Fury, the 17th Season of the Battle Pass! - News - War Thunder