Darkest Hour - Dev Diary #18 - Tech Tree Part 2

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Feb 24, 2009
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Here we are today for the second DD about our new tech tree! No more waiting, here it is!


The first unarmed airplanes for reconnaissance are introduced in 1910 and they soon evolve in the first real Interceptors and MultiRole fighters during the Great War. Naval Torpedos Brigades are also activated and upgraded by the Interceptors and the Multirole branches. There are 16 different models for Interceptors and 13 for Multi-Role Fighters.
The first Tactical Bombers are introduced in 1911 whereas the first generation of four-engine bombers are introduced in 1914 (and will evolve in Strategic Bombers and eventually Intercontinental Strategic Bomber in 1958). There are 13 different models for Tactical Bombers and 10 for Strategic Bombers.
The first Naval Bombers are introduced in 1918 (9 models), the Air Transport Planes in 1926 (6 models) and the Close Air Support in 1934 (8 models).
We've also introduced the Seaplane as a new Naval Brigade which increases the reconnaissance value of a ship. They are introduced in 1911 whereas the first Carrier Air Group is introduced in 1922 (9 CAG models).

Air Doctrines

The first Air Doctrines are introduced before the Great War, with the Powered Flight Concept followed by the Reconnaissance Plane Utilisation, the Air Duel Doctrine and the Bombdropping Doctrine.
With the start of WWI these doctrines are refined and evolve with the introduction of the Close Airsupport Concept, the Naval Aerial Support and Maritime Attack Concepts and obviously the Flying Circus Doctrine.
During the interwar period there are some doctrines that will lead you to the WWII doctrines which are the known techs you're already familiar with, take a look at their names and you'll see. Even if the names are familiar, they are not the same techs as they may have different bonus than what you'd expect.
For the beginning of the cold War, we've created whole new branches of air doctrines. They are two paths for the post-WWII techs for interceptors and multirole fighters:
- Defensive Air Superiority (Warsaw Pact and Asian States Doctrine)
- Offensive Air Superiority (NATO / Israeli Doctrine)
whereas for Tactical Bombers and CAS the following paths are available:
- Bomber priority (Target Destruction Doctrine)
- CAS priority (Land Units Destruction Focus, with focus on Jungle Operations)
There are also two different paths for Strategic Bombers and Missiles:
- Strategic Bomber Focus
- Strategic Missile Focus
The Airborne Assault and Naval Bombardment doctrines do not have differentiated paths, but they both have their own post-WWII doctrines.


Destroyers starts as Torpedo Gunboats in 1885 and evolve into Missile Destroyers in 1955 (10 models).
Light Cruisers start in 1881 and evolve into Missile Light Cruisers in 1953 (9 models).
Heavy Cruisers start as Armored Frigates in 1873 and evolve intoMissile Heavy Cruisers in 1953 (9 models).
Battlecruisers are introduced in 1906 and evolve into Modern Battlecruisers in 1951 (only 6 models).
Battleships are introduced in 1874, become Dreadnoughts in 1904 and finally evolve in Modern Battleship in 1947 (10 models). The Super Heavy Battleships are introduced in 1937 and have only 2 different models.
The first Converted Carrier are introduced in 1922 and evolve in the standard Carriers (8 models) whereas the Seaplane Carriers are introduced in 1912 and evolve in the Light Carriers (7 models).
Submarines are introduced as Dive Boats in 1896 and evolve in Modern Submarines in 1955 (10 models).
There are 4 different models for Transport Ships (this will probably be subject to changes).
In this tab you can also see the ASW Naval Brigade (6 models) and the Naval Torpedos branch which increases the Convoy Attack and Naval Attack of Destroyers, Submarines and sometimes Naval Bombers (again, the bonus is immediate and no events/annexations are needed).

Naval Doctrines

The first Naval Doctrines are the Engagement Theories introduced in 1890. This branch will unlock most of the other branches.
The Engagement Tactics branch is divided into two separated, mutually exclusive paths: Fleet-in-Being and Indirect Approach. I guess you might have expected that. :D
Now, below Engagement Tactics you can find the Carrier Tactics, introduced in 1925. This is divided into two paths too, but they are not mutually exclusive, you can research both. The Scouting Focus path focuses on Carriers as part of a naval task force and the engagement with enemy fleet, whereas the Aerial Supremacy focuses on the CAG and the missions it can perform (so for instance it grants increased efficiency for Port Strike and Airbase Strike).
The Naval Supremacy branch is focused on the defence of convoys and therefore it gives bonus to convoys, ASW and Naval Scramble. On the other hand, the Naval Interdiction branch is focused on Convoy Raiding and Submarine Warfare.
Finally the Amphibious Warfare branch introduced in 1916 gives bonuses to Amphibious Assaults (well, obviously! :D ) whereas the Logistic Support branch introduced in 1914 increases the range of ships.

Secret Weapons

We've already talked about the first WWI Experimental Tanks in the previous Dev Diary. The other Secret Technologies that can be discovered in this tab are: Rocket Interceptors, Flying Bombs and Flying Rockets, Electronic Computers, Semiconductors and Transistors, Nuclear Bombs, Ships with Nuclear Propulsion (Battleship, Super-heavy Battleships, Heavy and Light Cruisers, Submarines and Carriers), Air Cavalry Divisions, Air-to-Surface Missile (ASM), Surface-to-Air Missile (SAM), Mobile Mines and Teletanks. The Mobile Mines and Teletanks techs do not activate a new unit, but give bonuses to Engineering and Light Armor Brigades respectively.

To close this Dev Diary, here are some information related to the new technologies and modding:
- added 10 new research types: avionics, munitions, vehicle_engineering, carrier_design, submarine_design, fighter_design, bomber_design, mountain_training, airborne_training, marine_training;
- Added 20 more Research Type (components): Maneuver Tactics, Blitzkrieg Tactics, Static Defense Tactics and Medicine, rt_user_x (x = 1..16)
# Use new Technology page layout - allow for more techs and better view. 0 - use vanilla; 1 - use new
       1 #0 (Darkest Hour uses the new Technology page layout)
# Max active tech teams at a time (cannot be more then 50). Note: New Technology page layout will be auto-set for values above 5!
       5 #5
# Min active tech teams at a time (available teams regardless of current IC)
       1 #1
# Required IC for each tech team above the min
       20 #20

And of course, we've done a complete overhaul of all the tech teams for every nation, so expect new and different tech teams! :)
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It seems good.

The background pictures are also great.
But, there is a part of a swastika on the tail in the air doctrines picture.
I'm curious about the new TTs. I think the TT improvement team made a pretty good research for AoD (I understand that TTs need to be changed to accomodate the new components, but there won't be too many new to choose from in case of minor countries)
New Research Components? ACE! Have been wanting this for a while: there just aren't enough skill categories at the moment, particularly for mods that span a large time frame. This will free up enough components to let me create the unique tech teams I have wanted (from routine stuff like 'Materials Science', 'Jet Propulsion', 'Small Arms', to cool stuff, like 'Tesla Research', 'Zombie Technology', etc;))

The ability to change max number of research slots, and to mod the IC required for each slot, is also a very useful addition. Proper respect is due to the DH team for paying attention to modding possibilities. A BIG thanks guys!
Humm... I doubt there were multiroles during ww1, fighters would fit better the date since only dedicated planes like bombers could actually carry bombs (unless you consider trowing grenades from planes bombing :p) and they couldnt fight other planes. I guess you wanted to differentiate the dogfight special planes and the classic biblanes. Do please give some soft attack to fighters since they were able to strafe the trench lines.
I really like the new depth of these techs.