Hearts of Iron IV - The Invisibles (mod description) 
Royal Hellenic Air Force, technology tree 
Fighter
Naval Bomber
Close Air Support
1933
GRE_early_fighter.png
GRE_CAS1.png
1936
GRE_fighter1.png
GRE_naval_bomber1.png
GRE_CAS2.png
1940
GRE_fighter2.png
GRE_naval_bomber2.png
GRE_CAS3.png
1944
GRE_fighter3.png
GRE_naval_bomber3.png
1945
1950
GRE_jet_fighter1.png
GRE_jet_fighter2.png
Avia BH-33
Avro 652 Anson
Curtiss SBB2C Helldiver 
Dornier do 22kg
Fairey Battle B1
Fairey III
Gloster Gladiator
Hawker Hurricane
Potez 633 B2 Grec 
PZL P.24 
T-33 Shooting Star
F-84F Thunderstreak
Scout Planes
Transport Plane
1933
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Ju 52
1936
GRE_scout_plane_1_1.png
Potez 25 A2
1940
GRE_scout_plane_2_2.png
Henchel 126
Tactical Bomber
Strategic Bomber
Heavy Fighter
1933
GRE_early_bomber.png
Breguet Br.19 A2
GRE_heavy_fighter1.png
1936
Bloch 151 MB
GRE_tactical_bomber1.png
Airspeed oxford
GRE_heavy_fighter2.png
1940
Spitfire
GRE_tactical_bomber2.png
Blenheim Mk.I
GRE_heavy_fighter3.png
1944
Tomahawk
GRE_tactical_bomber3.png
Blenheim Mk.IV
GRE_strategic_bomber1.png
Leo 451G
GRE_strategic_bomber2.png
A-30 Martin
GRE_strategic_bomber3.png
Martin Maryland
1945
GRE_jet_tactical_bomber1.png
RT-33A
1950
GRE_jet_tactical_bomber2.png
F-84G Thunderjet
GRE_jet_strategic_bomber1.png
R-52 Hera