Hey everyone!
The next Skyline Sim public playtest opens on September 7, 2026 at 22:00 UTC, and everyone is welcome. Whether you played last time or are about to start your first airline, we'd love to have you join us.
We've spent the break rebuilding airline founding, bringing seasons and a new weather simulation to the globe, and working through the systems behind schedules, crews, passengers and daily operations. Some changes will be obvious as soon as you open the game. Others are about making your airline's plans line up with what actually happens when its flights operate.
How to join
Visit the main Skyline Sim Steam page, find the playtest section and click Request Access. Install Skyline Sim Playtest through Steam once access is available.
The playtest is open to everyone, including new players. We begin at 22:00 UTC on September 7.
Before you start
This is a development playtest, not the finished game. Expect bugs, rough edges, unfinished elements and systems that still need balancing. The game will continue to change as development progresses.
We recommend starting a fresh airline for this playtest. Saves using the previous booking-system format are no longer compatible. Affected saves are marked as incompatible in the main menu.
What's changed since the previous playtest
A new start for your airline
The main menu and airline-founding experience have been rebuilt around the globe. Choose your founding year and founder, select a country and base airport, create your airline's identity, appoint its leadership and sign the founding charter.
Country selection now has its own globe layers, airport selection includes arrival and departure boards, and you can see your airline's branding take shape during setup. We've also corrected portrait framing and issues with founding progress and confirming your choices.
A changing world outside your aircrafts
The globe now changes with the seasons, following the simulation calendar. Its atmosphere, visible sun, daylight and transition into night have been reworked, alongside fixes for coastlines, night lighting and texture alignment.
Weather has been rebuilt as a connected simulation, not just a visual layer. Moving weather systems, fronts, cloud layers and surface snow feed into the world you see. Volumetric clouds are linked to those conditions, with different cloud types represented in the sky.
A dedicated weather view lets you inspect tracked systems and their coverage, with a collapsible panel for weather information. Forecasts now include uncertainty, so future conditions are not presented as a guaranteed outcome. AI flight operations also use the shared weather simulation.
We've worked on cloud movement, visibility from orbit, fog and low-cloud representation, excessive upper cloud cover, snow display and cloud coverage around moist low-pressure systems. Globe and cloud rendering have also received performance work, including at close zoom.
Finding your way around
The in-game interface has received updates to navigation, contextual actions, notifications and simulation controls. We've refined the presentation of pause, resume, speed changes, time advancement and saving, alongside changes to spacing, typography and readability.
Network planning now exposes more information about bookings and connections. Slot screens provide more context about route slot packages and historical rights, while the aircraft rotation timeline shows when each aircraft will be ready.
Schedules that account for the whole aircraft journey
Flight planning now checks an aircraft's commitments against a shared timeline, including its other flights, maintenance downtime and any positioning flights needed to reach the next departure airport.
Timetable changes are kept in sync with the flights that actually operate. We've tightened checks around conflicting time changes, invalid Auto Schedule plans and fleet changes that would interfere with existing plans.
AI aircraft positioning has also been corrected, with ferry movements accounted for when an aircraft needs to move between airports.
More complete airport slot coordination
Arrivals and departures now count against shared airport movement capacity, with additional checks on capacity within 15-minute windows.
Keeping historical slot rights is based on flights actually operated, with justified non-use taken into account. Allocation now includes rules for new entrants, timing flexibility, regional differences and capacity waitlists. AI airlines also retain historical rights and take part in waitlist promotions.
Level 2 airports now use schedule facilitation. Accepting an offer and applying its timing changes are handled together, and more slot-coordination updates and short-notice awards arrive through the inbox.
Crew availability, reserves and recovery
Crew availability now accounts for location and assigned duties, rather than treating a crew member as available simply because they are on the roster. Assignments are checked against duty limits, training and operational requirements, and are rechecked after changes to flight operations.
Workforce planning exposes shortages of qualified crew, and reserve planning has been aligned with usable capacity. Crew recovery actions are checked together before being applied.
AI workforce planning has also been updated so that staffing availability feeds into its operations.
Maintenance connected to the operating schedule
Maintenance visits now account for the aircraft's physical location, any positioning required and whether the facility can handle the visit. These requirements feed into the aircraft availability used by scheduling.
The maintenance interface reflects operational consequences more accurately, and maintenance-control events can appear in the inbox. AI airlines also have a more complete maintenance lifecycle tied to their aircraft operations.
Flight disruptions and recovery decisions
We've reworked how operational incidents are tracked through to their outcomes, including the handling of player recovery decisions. Those decisions use the current simulation time, with more consistent checks around dispatch timing, diversions and airport constraints.
Regulatory findings now have their operational consequences enforced more consistently. We've also corrected differences that could appear when flight operations crossed midnight or were processed during a time skip.
AI operations have been brought into closer alignment with the rules used by the rest of the simulation, including weather, aircraft positioning, crews and maintenance.
Bookings, connections and passenger journeys
Bookings are now tracked persistently as passengers move through their journey. Seat availability is tracked by cabin and reconciled with the capacity of the flights actually operating.
We've corrected passenger accounting around cancellations and cabin capacity, and connected booking progression, disrupted-passenger recovery and financial settlement more closely.
Demand and connection calculations have also received substantial work, including fixes for outdated connection offers and improvements to how booking activity is carried through time skips. This includes both your network and connections involving AI airlines.
Sponsorships, charters and airline reputation
Sponsorship agreements now handle package ownership, activations and hospitality delivery more consistently. Sponsor results are more closely tied to what your airline actually delivered, and charter settlement has been connected to those commercial outcomes.
Reputation calculations now draw on evidence from your airline's activity, alongside changes to brand positioning. Daily financial postings, payment obligations and cash settlement have received fixes and performance improvements, including corrected ordering of cash-history entries.
Simulation speed, saves and reliability
Fixed an issue that could leave the live game clock frozen. We've also reworked how the simulation advances during time skips, reducing repeated work across flight operations, bookings, weather and AI airlines.
A large part of this work targets memory use during longer simulations and skips. The aim is to spend less time rebuilding information the game already has and keep less unnecessary data in memory as your airline grows.
We've added more checks for differences between normal play and fast-forward, and regression tests around schedules, slots, crews, maintenance, bookings, saves and flight operations. Save restoration fixes also cover older AI and weather data, although saves using the previous booking format remain incompatible.
The previous preset scenario modes have been retired.
Performance is still something we want to hear about during this playtest, especially with larger airlines and longer time skips. This work is not a claim that every slowdown or simulation issue has been solved.
Tell us what happens when you play
Please report bugs and share suggestions at feedback.skylinesim.app.
For a bug report, tell us what you were doing, what happened and what you expected instead. Steps to reproduce the issue and screenshots are especially helpful. For performance problems, include your computer specifications, roughly how large your airline is, and whether the slowdown happened during normal play or a time skip.
We also want to hear about the moments that aren't technically bugs. Was it clear what to do after founding your airline? Could you understand why an aircraft or crew wasn't available? Did managing a larger schedule become repetitive or frustrating? Those experiences matter too.
You don't need to suggest a fix. Knowing where you got stuck is already useful. Please don't assume a problem is too small to report just because the game is still in development.
Thanks to everyone coming back, and welcome to everyone joining us for the first time. We're looking forward to seeing your airlines and hearing how it goes.
September 7, 2026. 22:00 UTC. Open to everyone.