Diana Hope (Grasshopper) wrote:
This may be different for different forms of aikido, but I've been told that in Aikikai, you only get to call someone "sensei" when they're yondan or higher.
Your information is not very accurate, I'm afraid. In Aikikai, the evolution is from Fukushidoin to Shidoin to Shihan. Anybody who teaches a class, whether aikido or chemistry or painting is called sensei.