Games like Watch Your Helmet
Games like Watch Your Helmet include Universe Sandbox, Kerbal Space Program, SpaceEngine, Spaceflight Simulator, and Elite Dangerous. We matched them by the tags players give Watch Your Helmet on Steam (Space Sim, Experimental, 2.5D, Space, and Realistic): closest matches first, and among equally close ones the better-known games.

Universe Sandbox
Shared: Space Sim · Space · Realistic

Kerbal Space Program
Shared: Space · Space Sim · Simulation

SpaceEngine
Shared: Space Sim · Space · Realistic

Spaceflight Simulator
Shared: Space Sim · Space · 2D

Elite Dangerous
Shared: Space Sim · Space · Simulation

X4: Foundations
Shared: Space Sim · Space · Simulation

Reentry - A Space Flight Simulator
Shared: Space Sim · Space · Flight

Hardspace: Shipbreaker
Shared: Space · Space Sim · Simulation

STAR WARS™: Squadrons
Shared: Space · Flight · Simulation

Kerbal Space Program 2
Shared: Space · Space Sim · Realistic

Microsoft Flight Simulator (2020) 40th Anniversary Edition
Shared: Realistic · Flight · Simulation

Cosmoteer: Starship Architect & Commander
Shared: Space · Space Sim · 2D

X-Plane 11
Shared: Realistic · Flight · Simulation

Avorion
Shared: Space Sim · Space · Flight

BeamNG.drive
Shared: Realistic · Simulation · Physics

Exo One
Shared: Space · Flight · Space Sim

Endless Sky
Shared: Space · 2D · Simulation

Liftoff®: FPV Drone Racing
Shared: Flight · Realistic · Simulation

Juno: New Origins
Shared: Space Sim · Flight · Realistic

Empyrion - Galactic Survival
Shared: Space · Space Sim · Simulation

X Rebirth
Shared: Space · Space Sim · Simulation

Flight Of Nova
Shared: Space Sim · Flight · Realistic

Uncrashed : FPV Drone Simulator
Shared: Flight · Realistic · Simulation

Starpoint Gemini 2
Shared: Space · Space Sim · Simulation