Steam News14 January 20265mo ago

Meco 0.4.0: Turbopumps Are Here

Three New Missions Mission 7: Gearing Up — gear reduction and torque transitions Mission 8: Pump It Up — an RL-10 inspired LOX pump on a test stand Mission 9: Turbine Trials — F-1 engine turbopump dynamics Mission 9 was

In this update3

Full notes

Full Meco Rocket Simulator update

Read the full published notes in a cleaner layout. The original post stays linked below.

What changed

1 fix2 additions8 changes0 removals

Gameplay
UI and audio

changedThree New MissionsMission 7: Gearing Up — gear reduction and torque transitions

changedThree New MissionsMission 8: Pump It Up — an RL-10 inspired LOX pump on a test stand

changedThree New MissionsMission 9: Turbine Trials — F-1 engine turbopump dynamics

changedThree New MissionsMission 9 was honestly my favorite to build. I spent way too many hours reading old NASA documents about the Saturn V turbopumps. The F-1 pumped something like 15,000 gallons of kerosene per minute. Wild. You won't be replicating that exactly—Meco's models are simplified—but you'll feel the same tradeoffs those engineers dealt with. Admission ratios, efficiency curves, that moment when you realize you can't just crank everything to max.

addedThree New MissionsThe sim engine got real turbine loss modeling now. You can see actual eta_ts values (that's total-to-static efficiency, for the uninitiated) and watch how your design choices ripple through the whole system. New sampler tools let you visualize pump and turbine performance curves as you tweak things.

fixedBig UI ImprovementsSome editor stuff that's been bugging me for months, finally fixed:

Meco Rocket Simulator changes

changedMission 7: Gearing Up — gear reduction and torque transitions

changedMission 8: Pump It Up — an RL-10 inspired LOX pump on a test stand

changedMission 9: Turbine Trials — F-1 engine turbopump dynamics

changedMission 9 was honestly my favorite to build. I spent way too many hours reading old NASA documents about the Saturn V turbopumps. The F-1 pumped something like 15,000 gallons of kerosene per minute. Wild. You won't be replicating that exactly—Meco's models are simplified—but you'll feel the same tradeoffs those engineers dealt with. Admission ratios, efficiency curves, that moment when you realize you can't just crank everything to max.

addedThe sim engine got real turbine loss modeling now. You can see actual eta_ts values (that's total-to-static efficiency, for the uninitiated) and watch how your design choices ripple through the whole system. New sampler tools let you visualize pump and turbine performance curves as you tweak things.

Three New Missions

Mission 7: Gearing Up — gear reduction and torque transitions
Mission 8: Pump It Up — an RL-10 inspired LOX pump on a test stand
Mission 9: Turbine Trials — F-1 engine turbopump dynamics

Mission 9 was honestly my favorite to build. I spent way too many hours reading old NASA documents about the Saturn V turbopumps. The F-1 pumped something like 15,000 gallons of kerosene per minute. Wild. You won't be replicating that exactly—Meco's models are simplified—but you'll feel the same tradeoffs those engineers dealt with. Admission ratios, efficiency curves, that moment when you realize you can't just crank everything to max.

The sim engine got real turbine loss modeling now. You can see actual eta_ts values (that's total-to-static efficiency, for the uninitiated) and watch how your design choices ripple through the whole system. New sampler tools let you visualize pump and turbine performance curves as you tweak things.

Big UI Improvements

Some editor stuff that's been bugging me for months, finally fixed:

Pin the component editor so it stays open while you work on the schematic
Simulation auto-runs when you change things (no more clicking Run after every tiny edit—this alone has saved me so much frustration)
Nudge controls with +/- buttons and mouse wheel for fine adjustments
Colorblind-friendly chart colors using Okabe-Ito. Should've done this ages ago.

Try It Out!

I also built a bunch of internal tools to author missions faster. More content is coming.

If you bounced off Meco before because it felt overwhelming—honestly, fair—this might be a good time to try again. The new missions hold your hand a bit more through the turbomachinery concepts.

And if you play and have a minute, a Steam review really does help. Visibility is everything for a small project like this.

Source

Steam News / 14 January 2026

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