Gas measurement eddy current probe

A gap measurement probe for measuring the gap between a tube and an antivibration bar in a steam generator includes a shaft and first and second sensors mounted on a C-shaped end of the shaft. Each of the sensors is self orienting and includes a flexible coil form having a first portion fastened to the shaft and having a resilient second C-shaped portion surrounding a portion of the periphery of the shaft. A test coil is mounted on the second C-shaped portion of each of the coil forms and the test coils are arranged such that they extend about different portions of the circumference of the shaft so as to sense different portions of the circumference of the tube when the gap measurement probe is inserted in the tube. The probe self-orients in the U bend of the tube.