Hearts of Iron IV

Hearts of Iron IV 1.17.5

Version
1.17.5
Version Date
March 16, 2026
Links

Patch Notes

Warships of the Pacific - Patch Notes, 1.17.5

Admirals!

Tomorrow we release Warships of the Pacific and with it a big chunk of patch notes for everyone: 1.17.5.

PDX_Gorion will bring you a nicer intro with more of our thoughts in tomorrow’s release post; for now enjoy the Patch Notes.

UI

  • Implemented a simple equipment category dropdown and reset button in the model selector of the division designer
  • Updated equipment model sorting so that special projects are always are at the top
  • Implemented a more flexible pool priority system for equipment model sorting (and removed sorting cohorts)
  • Added more functionality to control group management
  • The Division Designer now uses the same model prioritization as on the map
  • The model selector UI now fits 5 list entries instead of 3
Balance

  • Fixed an "airforce" typo and increased Lindberg's leader trait for air range to a more meaningful 5%, from 1%
  • Reduced the mastery gain debuff France gets from "Victors of the Great War" to -15%
  • Updated "Fund the Navy" focus to take 35 days instead
  • All Puppets now get penalties to faction influence gain, ranging from -10% to -75% depending on their type
Gameplay

  • Broke out Nevada and Tennessee Class ships from Pennsylvania Class in USA naval OOB. Created separate classes
  • USA: Carrier Primacy now gives Essex Class carrier when the tech is unlocked
  • USA: Convoy Tactics now gives Casablanca Class escort carrier design when the special project is unlocked
  • Japanese Carrier Submarine special project now creates I-400 design.
  • Added Leander and County class cruiser designs to Australia to reflect active designs.
  • Added Coastal Defense Ship tech to UK.
  • Added Erebus-class Monitor design to UK (based on Coastal Defense Ship hull).
  • Added HMS Erebus and HMS Terror to Britain's Reserve Fleet.
  • The state of Banat is now included in the option "All of Transylvania" in the Second Vienna Award event chain
  • Added starting paratrooper template to Japan
  • When a fleet decides to repair, it will favor dockyards with more repair slots more strongly now
  • Rebalanced faction influence gain from various sources: Increased for Warscore and Lend Lease, decreased for Scientists, also slightly increases passive initiative gain
  • Added British Monitors namelist for ships.
  • Added Erebus-class 1939 refit design for Britain's 1939 bookmark.
  • Changed "I-400 Class" name to the Japanese "Sentoku Class".
  • While in the model selector grid, it now shows thumbnails of models
  • Successfully imposing naval blockade should no longer restrict your access to trading through blockaded regions
Performance

  • Fixed issue where 'RepairNow' button spams pathfinding calculations
  • Made adjustments to how the game handles large lobbies to smooth out that experience.
AI

  • Tweaked German equipment production to better be in line with their templates, additionally improved decision making for: Convoy raiding, force concentration, and lend-leasing or selling equipment close to war breaking out
  • USA: improved the AI's naval templates and their prioritisation of which to produce
  • Japanese starting paratrooper template now has 3 paratroopers (instead of 2)
  • The Ma Cliques will now not do their mutual guarantees focus until the late game, and the SIK ai will now not become a Soviet puppet unless they fully control all their owned states
  • Update USA strategy so they fight better in the pacific
  • Belgium now correctly unlocks its "Division d'Infanterie" unit
  • Increased research weights causing various navy heavy countries to research more naval technologies
  • The AI now uses 'fund the navy' and will wait more with naval doctrine selection until it has the bonus active
  • The AI will now train their ships more than previously, if possible due to fuel restraints
  • Tweaked AI research weights for Fire Control Methods
Modding

  • Implemented support for sending chains of console commands using '&&'
  • Show icon weights in icon selector of designers when debugging
  • Adds support for SubUnitDefinition-based equipment pools for icons
Bugfix

  • Fixed an issue where scavenged equipment caused infantry to wear uniform from another country
  • Fixed decision timers not progressing
  • Changed an icon for USA jet_strat_bomber and jet_tac_bomber to fix errors that occur without the prototype vehicles pack.
  • Fixed floating geometry on the Big Bob super heavy tank for New Zealand
  • Fixed tank scale for BfB and the same type of tanks in other DLC:s
  • Fixed "Zuikaku" provided through a Japanese focus incorrectly being called "Zaikaku".
  • Japanese Missile Submarine special project is now no longer incorrectly called "I-400-class Missile Submarine" - instead the "I-400 Submarine Carrier" name has been moved to the Japanese Carrier Submarine special project.
  • Fixed a potential crash when a division template was being removed while you had exiled divisions in transfer
  • Added triggers to the "Coalition of Liberty" faction goal, so that it isn't available and can get auto-completed if the right criteria isn't fulfilled
  • Fixes typo in AST focus tree: 'Habsbugs' -> 'Habsburgs'
  • Fix some timing issues with decisions
  • Fixed the Maphilindo flag displaying upside down
  • Fixed an issue where two Khotan Ma advisors became unavailable when forming China
  • Japan - Fixed an issue where the decisions from the focus East Asia Development Board wouldn't properly provide the promised factories
  • Warlords - Fixed an issue where the Reach out to X country focuses in the shared branch could be taken even if said country no longer existed
  • Paraguay - Fixed an issue where the spirit Guión Rojo wouldn't actually give any manpower
  • Fixed an issue where the Japanese tactic Grand Banzai Charge would be enabled from the start instead of being enabled by focus
  • Soviet Union - Fixed an issue where giving a Sinkiangi puppet control of Pamir would lock the Soviets out of taking the focus Gobi Gambit
  • Fixed an issue where Spanish general Enrique Líster wouldn't get Stalinist sympathies if Spain had completed the focus The Popular Front
  • Fixed an issue where a Belgian advisor and two Italian national spirits were attempting to use state based intel modifiers on a country scope
  • Austria: fixed an issue where Godwin von Burmowski would show up in the air chief role without giving air xp, he has been moved to a high command role
  • France: Fixed an issue where the focus Grow the Empire would be unavailable if the states were controlled by a puppet Congo
  • Tweaked the scaling requirements of the Faction Goal "Develop Joint Research Practices" to make it easier to understand, and faster to complete.
  • Updated localization of british infantry weapons to use the correct whitespace
  • Fixed a bug where auto repeat spy operations was not correctly persisted between save & loads
  • Fixed a bug where screens without depth charges would try and keep fighting submarines
  • Fixed a bug where submarine detection chance was not correctly calculated
  • Fixed an issue where some models were incorrectly showing up or missing
  • Fixed a number of typos and other small writing issues