Also found in: Dictionary.
acceleration error[ak‚sel·ə′rā·shən ‚er·ər]
That error resulting from change in a craft's velocity vector: specifically, either the deviation of an aircraft magnetic compass caused by the action of the vertical component of the earth's magnetic field on the compass magnets when the compass card is thrown off level by accelerations of the aircraft; or the deflection of the apparent vertical, as indicated by an artificial horizon, due to acceleration.
Aircraft accelerates from 180 knots to 210 knots when on course of 090°. The magnetic compass, however, shows as if aircraft has turned from 090 to 120°. Similarly, when aircraft decelerates from 180 knots to 160 knots in a straight and level flight, the compass shows a turn to the left—in this case to 060°. In both cases, compass comes back to the original course as soon as the acceleration/deceleration has stopped.
Note: These changes are for the Northern Hemisphere. The changes will be reversed if the aircraft is operating in the Southern Hemisphere and if the compass has been correctly dip-compensated for the Southern Hemisphere.
ii. An error in a bubble sextant caused by mechanical inertia during changes in an aircraft's velocity.