| 释义 |
Lead angle
| (Steam Engine) | the angle which the crank maker with the line of centers, in approaching it, at the instant when the valve opens to admit steam. |
See also: Lead lead angle
lead angle[′lēd ‚aŋ·gəl] (design engineering) The angle that the tangent to a helix makes with the plane normal to the axis of the helix. (metallurgy) The angle at the point of welding between an electrode and a line perpendicular to the weld axis. (ordnance) The angle between the line of sight to a moving target and the line of sight to a point ahead of the target. A dropping angle. (physics) The phase difference between a sinusoidally varying quantity and a reference quantity which varies sinusoidally at the same frequency, when this phase difference is positive. Also known as angle of lead; lead; phase lead. lead angle i. The angle by which an allowance is made for the radius of turn to enable the aircraft to role out on the desired track. The aircraft must commence its turn to the track before reaching it; otherwise, the aircraft will overshoot the desired track. This lead angle depends on the true air speed (TAS), distance, wind velocity, and aircraft rate of turn. In a given time out, its value is constant irrespective of the TAS.
ii. The angular difference between the line of sight and an aiming line. Also called the angle of lead |