Airpseed LOG ANALYSIS in EK3 Normalised Innovation

Hi, I am learning to interpret the log files looking at video and comparing to mine logs, in the EK3 Normalised Innovation graph I see that airspeed sensor datas not giving me any result , I searched about QRTl mode mandorites but I didn’t see airspeed but even if that fact I wanna use it also in any other modes, but always gave me the perfectly straigth line in graph like:

I wanna know why is showing me like that, also I am trying the hanging my quadplane right now, it’s in first tests and in indoor. so GPS is not working .