lbf
Units & Measurements abbreviation · Engineering Unit
| Stands for | Pound-force |
|---|---|
| Categories | Units & Measurements |
lbf stands for Pound-force, an engineering unit abbreviation.
The force of gravity on one pound of mass at standard gravity, about 4.448 newtons. US engineering uses lbf for thrust, structural loads and pull strength, adding the f to separate force from mass (lbm).
Example: Each engine generates 27,000 lbf of takeoff thrust.
Usage notes
US rocket and jet thrust is quoted in lbf; the Saturn V's first stage produced about 7.5 million lbf. Because everyday "pounds" covers both force and mass, unit errors happen: NASA's Mars Climate Orbiter was lost in 1999 when one team supplied data in pound-force seconds and another expected newton-seconds.