Abstract: Stratospheric airships are at present a focus of worldwide near-space development due to their specific applications. Because of the reduction of buoyancy provided by per volume of the stratospheric airship in comparison with normal mid-low attitude airships, a stratospheric airship exhibits a cyclic relationship between its hull volume, drag and weight. Realization of the lightweight of the airship is therefore the most important topic of stratospheric airship development which attracts high attention. This article introduces some main methods and techniques to realize lightweight structure, and provides a review of current research on stratospheric airships with lightweight structures. Advantages and drawbacks of these methods are compared with each other. The technique of deployable stratospheric airships is analyzed. The results reveal that improving the material performance of the envelope, changing the structural style and developing a new type of deployable airship are the main methods to realize lightweight of stratospheric airships. Among them, the new type deployable airships can considerably reduce structure weight and manifest excellent development potential.

Key words: near-space, stratospheric airships, deployable airships, envelope, lightweight