g/cm³ to lb/in³
Aerospace is the one industry that measures density in pounds per cubic inch. An aluminum airframe alloy is 0.0975 lb/in³; a titanium part is 0.160; a steel landing gear fitting is 0.283. The conversion from the datasheet's g/cm³ — aluminum 2.7 — goes through 0.036127292, a number that carries both the 1959 pound and the inch cubed.
lb/in³ = g/cm³ × 0.036127292
1 g/cm³ = 0.036127292 lb/in³ — the 1959 pound over the inch cubed
The factor is exact — derived from SI definitions and the 1959 yard/pound agreement.
Common g/cm³ to lb/in³ Conversions
| g/cm³ | lb/in³ | Material / context |
|---|---|---|
| 1 g/cm³ | 0.0361 lb/in³ | The definitional anchor. |
| 2.7 g/cm³ | 0.0975 lb/in³ | Aluminum 6061. |
| 4.43 g/cm³ | 0.160 lb/in³ | Titanium 6Al-4V. |
| 7.85 g/cm³ | 0.284 lb/in³ | Carbon steel. |
| 8.96 g/cm³ | 0.324 lb/in³ | Copper. |
| 19.3 g/cm³ | 0.697 lb/in³ | Gold. |
Engineering Context
Density links the mass and volume families on this site — it is their ratio. For the mass numerator, the kg to g and lbs to kg converters carry the same 1959 constants that appear here; for the volume denominator, the liters to mL and cubic feet to cubic meters pages supply the cubed lengths. The density hub collects all ten converters in this family.
More: Lb In3 To G Cm3 · G Cm3 To Lb Ft3 · G Cm3 To Kg M3 · Density
Related Unit Converters
Frequently Asked Questions
Why does aerospace use lb/in³?
Because aircraft weight is computed from inch-based geometry. A part's volume in cubic inches, multiplied by density in lb/in³, gives weight in pounds directly — no foot-to-inch conversion mid-calculation.
Is aluminum really 0.0975 lb/in³?
Yes — 6061 aluminum is about 2.70 g/cm³, which converts to 0.0975 lb/in³. Aerospace weight engineers know it by heart alongside steel's 0.283 and titanium's 0.160.
How does density affect aircraft weight?
Directly — every airframe part's weight is volume × density. Switching from aluminum (0.0975 lb/in³) to titanium (0.160) increases a bracket's weight by 64%.