Current systems such as satellites, aircrafts, automobiles, turbines, wind power generators and traffic controls are becoming increasingly complex and/or highly integrated as prescribed by the SAE-ARP-4754 Standard. Such systems frequently require accurate generation, distribution and time or phase synchronization of signals with different frequencies that may be based on one reference signal and frequency. But the environment fluctuations or the non-linear dynamics of these operations cause uncertainties (skew and jitter) in the phase or time of the reference signal and its derived signals. So, techniques to reduce those causes or their effects are becoming important aspects to consider in the design of such systems. The PLL techniques are useful for establishing coherent phase or time references, jitter reduction, skew suppression, frequency synthesis, and clock recovery in numerous systems such as communication, wireless systems, digital circuits, rotors, and others.This paper shows the use of PLL (Phase-Locked Loop) techniques for accurate time or phase synchronization in aerospace and automotive systems. This is exemplified by simulating one PLL technique to reduce the skew and jitter and to synchronize: 1) time or 2) phase of a control system composed of: 1) two computation and communication lines; or 2) two classical rigid rotors.The preliminary results suggest that the PLL technique used: A) is very efficient to accurately synchronize: 1) the two computation and communication lines; or 2) two classical rigid rotors in 1) time or 2) phase; B) reduces or even eliminates the unwanted effects of instability and uncertainties; and C) can be used in aerospace or automotive systems.