System and method of controlling the circumference of a pressure tank mounted within a vacuum tank

An aircraft, comprising:

• a fuselage;
• a tank system included with the fuselage and comprising:
• a vacuum tank having a vacuum tank main portion having a vacuum tank skin;
• a pressure tank mounted within the vacuum tank and having a pressure tank main portion comprised of one or more pressure tank skin segments having a total circumference that is less than that of a complete circle, resulting in one or more longitudinal gaps respectively between the one or more pressure tank skin segments;
• one or more gap control mechanisms configured to control a width of the one or more longitudinal gaps in a manner facilitating movement of the one or more pressure tank skin segments between at least the following positions:
• a retracted position in which there is a radial gap between each pressure tank skin segment and the vacuum tank skin;
• and
• a fully extended position in which the pressure tank skin segments are in contact with the vacuum tank skin.

A method of varying a circumference of a pressure tank mounted within a vacuum tank, comprising:

• adjusting, using one or more gap control mechanisms, a width of one or more longitudinal gaps respectively between one or more pressure tank skin segments of the pressure tank, in a manner causing movement of the one or more pressure tank skin segments between at least the following positions:
• a retracted position in which there is a radial gap respectively between each pressure tank skin segment and a vacuum tank skin of the vacuum tank;
• and
• a fully extended position in which the pressure tank skin segments are in contact with the vacuum tank skin.