Although the flights of stratospheric balloons used for various scientific observations and technological experiments do not take place in the void of space, stratospheric balloons may be placed in the same fields as rockets and satellites, namely space science and technology. This, of course, goes without saying for planetary balloons that are transported into outer space on space vehicles. Organizations that conduct research and development, and that launch and perform operations with this type of scientific ballooning are usually associated with each country's meteorological organizations and space research and development organizations.

Stratospheric balloons are giant pressurized membrane structures that float in the thin atmosphere of the stratosphere. Their volumes range from a few tens of thousands of cubic meters up to several hundred thousand cubic meters. Their flight characteristics are governed by complex relationships of fluid dynamics and thermodynamics. For planetary balloons, various atmospheric conditions that differ from those on the ground also come into effect. Consequently, performing systematic engineering design and analysis is a prerequisite for constructing and launching balloons. Aerologicalknowledge of the atmosphere is indispensable for conducting a flight. Such a foundation also ensures safety and reliability during flights. The aim of this book is to systematically describe the engineering aspects associated with scientific ballooning.