My sensei also teaches Chong Shin Kwan, a TKD/Karate hybrid, at the dojo. I suppose he just uses the colored belts of TKD in the aikido classes out of convenience. White is 8th kyu and yellow is 7th.
Our yellow belt requirements look similar to this...
Sean Constable wrote:
katatori ikkyo (irimi, tenkan, mae nage)
katate kosatori kotegeishi ( irimi, tenkan)
katate kosatori kokyunage
demonstration of 3 basic strikes empty handed and with bokken.
And some basic aiki taiso.
...although we were only actually tested on ikkyo, kotegaeshi, and kokyunage.