Mechanical problems in momentous projects of aerospace engineering

With the vigorous development of the momentous projects in aerospace en-gineering field, new mechanical problems emerge continuously. Therefore, the research on engineering mechanics plays a prominent role in the developments of the space technol-ogy. The launch and operation environment for spacecraft is becoming more stringent as the spacecraft nowadays is developing on the track of super high speeds, deep space explo-ration and multifunction. Large-area and large flexible structure equipped on the spacecraft has proposed new challenges on the dynamics of deployment in orbit, modal identification and rigid-flexible coupling dynamics. Meanwhile, high-precision and high-resolution earth-observing request leads to new problems of micro-vibration control and thermally induced vibration control in orbit. All these problems urge more accurate methods for ground sim-ulations and experiments. In this paper, we outline the new mechanical problems arising from the launch of spacecraft, in orbit operation, ground simulations and experiments, etc. We focus on coupled dynamics, aerodynamics, multi-body dynamics, structure dynamics and experimental mechanics. The new problems and development directions of engineering mechanics are discussed in the end.