Factorio 2.1.21 changes the tradeoff behind space-platform speed.

A visible damage budget

Wube’s October 9, 2026 Friday Facts #448 explains that Factorio 2.1 ties collision damage to an asteroid’s remaining health. Shooting it before impact reduces the damage it can still inflict; asteroids are destroyed when that health is exhausted.

In 2.1.21 a medium asteroid deals 2,000 damage to a moving platform and 100 to a stationary one. These are version-specific figures, not a claim about the 2.0 stable branch.

Mass replaces an outsized width penalty

The revised drag component uses mass rather than width. Adding an edge tile therefore costs the mass of that tile instead of nearly imposing the penalty of an entire wider column. The new component is (mass / 200)^0.8, replacing width × 0.5; this is only the drag component, not the complete acceleration formula.

Wube says the formula is in 2.1.21 and affects existing platforms. Its testing found the largest losses on ships that excessively stacked thrusters, while wider ships and small starter platforms gained speed. Those are the developer’s test results.

Our analysis: compactness still matters

Removing width as the dominant speed penalty does not make empty floor free. More mass still needs more thrust. A wider layout may fit additional engines, but it also presents a different defensive frontage; fitting useful equipment into fewer tiles remains worthwhile.

The design question becomes what each added tile enables. Room for an engine, ammunition supply or production equipment has a purpose that a bare extension lacks. Compare alternative blueprints on the same branch with the same equipment quality and load rather than assuming a silhouette determines performance.

The announcement discusses an experimental branch. We have not benchmarked these layouts, and the examples do not establish an optimal ship for every route. Keep the version attached to any speed claim or blueprint recommendation.