A fluid level gauge assembly for measuring a level of a fluid in a fluid container is provided. The fluid level gauge assembly includes a first coaxial cable section having a first end and a second end, the first coaxial cable section including a first center conductor, a first outer conductor and a solid dielectric between the first center and outer conductor; a second coaxial cable section having a first end and a second end, the second coaxial cable section including a second center conductor, a second outer conductor and an air dielectric between the second center and outer conductor; and a coupling between the second end of the first coaxial cable section and the first end of the second coaxial cable section. The second coaxial cable section being disposed in a fluid for determining a level of the fluid.