We have updated our
Community Code of Conduct . Please read through the new rules for the forum that are an integral part of Paradox Interactive’s User Agreement.
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser .
How to read the diagrams
Each diagram lists the research fields required for research of the item.
Each diagram lists the specific theories and applications required for research of the item.
Some diagrams have warnings about the effects of certain research choices so be mindful of them before making your selection.
Points to keep in mind
The diagram threads use the same ID numbering system as State Machine's Technology Charts and Analysis pages and (of course) the Hearts of Iron tech database.
Many research items have the effect of deactivating other research choices e.g. research of an Improved Medium Tank with a 40mm+ Tank Gun automatically deactivates the 20mm+ and 30mm+ research options.
The diagrams list only the specific components needed for research. Be mindful of the fact that many of these components might require that multiple sub-components of their own be researched before your research goals can continue.
The diagrams are listed in platform groups e.g. all Light Tanks are listed together to aid in searching... at least how I would search if I was looking for something.
My use of colors, specifically blue , indicates only the required prerequisites that are part of the research progression (e.g. the 40mm+ requires successful research of the 30mm+ tank gun) and are components of a given diagram item.
Your research choices could very well result in an item I have marked green being listed as [color=FF9933]in the process of being researched[/color] or already successfully researched .
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Basic Dive Bomber
Required research fields:
Heavy Aircraft Research
Air Warfare Doctrine
Required components
Level 1 Theory:
Basic Bomber Development
Level 0 Application:
Blitz Bombing Doctrine
Level 1 Application:
Basic Light Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Improved Dive Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 5 Theory:
Improved Bomber Development
Level 5 Application:
Improved Light Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Basic TurboJet Dive Bomber
Required research fields:
Heavy Aircraft Research
Industrial Research
Required components
Level 8 Theory:
Advanced Bomber Development
Level 7 Application:
Basic TurboJet Bomber Engine
Level 8 Application:
Advanced Light Bomber Prototype Tests
Level 9 Application:
Teflon
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Basic Naval Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 1 Theory:
Basic Bomber Development
Level 1 Application:
Basic Medium-Range Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Improved Naval Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 5 Theory:
Improved Bomber Development
Level 5 Application:
Improved Medium Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Advanced Naval Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 8 Theory:
Advanced Bomber Development
Level 8 Application:
Advanced Medium Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Basic Torpedo Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 1 Theory:
Basic Bomber Development
Level 1 Application:
Basic Light Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Improved Torpedo Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 5 Theory:
Improved Bomber Development
Level 5 Application:
Improved Light Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Advanced Torpedo Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 8 Theory:
Advanced Bomber Development
Level 8 Application:
Advanced Light Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Basic Tactical Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 1 Theory:
Basic Bomber Development
Level 1 Application:
Basic Medium-Range Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Improved Tactical Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 5 Theory:
Improved Bomber Development
Level 5 Application:
Improved Medium Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Advanced Tactical Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 8 Theory:
Advanced Bomber Development
Level 8 Application:
Advanced Medium Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Semi-Modern Tactical TurboJet Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 11 Theory:
Semi-Modern Bomber Development
Level 11 Application:
Semi-Modern Medium Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Basic Air Transport
Required research fields:
Heavy Aircraft Research
Required components
Level 1 Theory:
Basic Bomber Development
Level 1 Application:
Basic Heavy Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Improved Air Transport
Required research fields:
Heavy Aircraft Research
Required components
Level 5 Theory:
Improved Bomber Development
Level 5 Application:
Improved Heavy Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Advanced Air Transport
Required research fields:
Heavy Aircraft Research
Required components
Level 8 Theory:
Advanced Bomber Development
Level 8 Application:
Advanced Heavy Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Basic Strategic Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 1 Theory:
Basic Bomber Development
Level 1 Application:
Basic Heavy Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Improved Strategic Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 5 Theory:
Improved Bomber Development
Level 5 Application:
Improved Heavy Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ
Advanced Strategic Bomber
Required research fields:
Heavy Aircraft Research
Required components
Level 8 Theory:
Advanced Bomber Development
Level 8 Application:
Advanced Heavy Bomber Prototype Tests
Green is an item that can be researched.
Rust is an item being researched.
Blue is an item that has been researched.
Toggle signature
After updating FAQ diagrams to v1.04, my mini-vacation will be over and I'll be mired in work and study again.
Here is the Hearts of Iron FAQ