# 0011: Grounded Newtonian Spaceship Flight

Status: Accepted

Date: 2026-05-25

## Context

The Sci-Fi Hard Vacuum cell promises grounded spaceship simulation with
flip-and-burn maneuvers, PDC/railgun/torpedo combat, and gravity-zone changes.
Arcade flight would undermine that cell identity.

## Decision

V5 uses a Newtonian flight model for Hard Vacuum ships. Thrust, mass,
orientation, recoil, drift, and gravity zones are modeled explicitly, with
assist layers exposed as accessibility and difficulty settings rather than a
replacement model.

## Consequences

- Ship combat tests must cover inertia and flip-and-burn behavior.
- Input and HUD must communicate velocity vectors and burn planning.
- PvP prediction work must respect deterministic ship-state integration.