Convert Pound square inches to Slug square feet

Convert Pound square inches (lb·in²) to Slug square feet (slug·ft²) instantly and accurately.

Pound square inches (lb·in²)
Slug square feet (slug·ft²)

Conversion Formula

slug·ft² = lb·in² × 0.0002158399317

About Pound square inches

The pound square inch (lb·in²) equals ≈2.926 × 10⁻⁴ kg·m², the standard US customary unit for motor and machinery rotors. Rockwell Automation, Parker Hannifin, and Allied Motion servo sizing catalogs express rotor inertia in lb·in²; US machine-tool spindle and conveyor drive specifications use lb·in². High-speed spindle rotors: 5-50 lb·in². 1 lb·in² ≈2.926 × 10⁻⁴ kg·m² = 1/144 lb·ft².

About Slug square feet

The slug square foot (slug·ft²) equals ≈1.3558 kg·m², the fundamental moment of inertia unit in US customary aerodynamics and spacecraft attitude dynamics. Pre-SI spacecraft inertia tensors are tabulated in slug·ft² - NASA Apollo CSM principal moments ranged 12 000-90 000 slug·ft². USAF flight manuals and NACA stability reports use slug·ft². 1 slug·ft² ≈1.3558 kg·m² = 32.174 lb·ft².

Quick Reference Table

Pound square inches (lb·in²)Slug square feet (slug·ft²)
1 lb·in²0.00021584 slug·ft²
2 lb·in²0.00043168 slug·ft²
5 lb·in²0.0010792 slug·ft²
10 lb·in²0.0021584 slug·ft²
25 lb·in²0.005396 slug·ft²
50 lb·in²0.010792 slug·ft²
100 lb·in²0.021584 slug·ft²

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