tachogram
/ˈtækəˌɡræm/
noun
- A record or graph produced by a tachometer, showing the speed of a rotating shaft or engine over time.
- Modern cars store tachogram data that can be used to diagnose performance issues.
- The mechanic studied the tachogram to see if the engine had been running at safe speeds.
- A tachogram from the test flight showed a sudden drop in rotor speed.