... most time consuming (several minutes, typically).3. Transfer alignment in a moving host vehicle, using velocity matching with analigned and operating INS. This method is typically several times ... which gyrocompassing is performed.Alignment accuracy is also a function of the time allotted for it, and the timerequired to achieve a speci®ed accuracy is generally a function of sensor errormagnitudes ... accurate clock. It has given us the time units of days, hours, minutes, andseconds we use to manage our lives, and we continue to use its rotation as ourprimary time reference, adding or subtracting...