A geophysical survey is conducted, using specialized instruments, to measure the gravity field by flying over a terrain of interest. A series of nominally parallel survey lines can be flown until a total region to be surveyed has been covered. The geophysical survey data is collected using an airship or self-propelled lighter-than-air craft sometimes referred to as a dirigible or blimp. In particular, a rigid airship may be used, that includes all extensions, like fins and a control car, attached to a rigid frame.