Originally Posted by
TiredSoul
Yeah there’s a more technical reason for it too....although I forgot
I can only speak to the 525's, but to service the hydraulic system you need flaps T/A and gear down. I believe that is the only condition under which the sight gauge is accurate. There's a placard on the reservoir about it. This way if you need a top off, there's no need to start engines just to move the flaps (although I've never needed one in 5+ years of Citation flying).
Whatever. Silly thing to complain about.