At the beginning of the 1950s the USAF engaged in various test programs to know the effects of weightlessness on man’s physical and mental performance. An easy way to gather Zero-G data were through parabolic flights: property executed vertical parabola that produced some seconds of weightlessness and sub-gravity. After using T-33‘s and F-89‘s, their standard asset for zero-G research became the F-94C, which offered a longer parabola due to its better performance and power.
Besides the human data acquired a comparative study with animals were undertaken. It seems they even removed cat’s vestibular organs during tests. Awful science.
In any case, it’s an alluring photo.