CRJ900/CRJ200 difference questions

[dcoded]

Hey,

After flying the CRJ 200 for a few years, and now operating the CRJ 900,
I have collected a few questions.

Why is there no requirement anymore to test the stab disconnect button on the first flight of the day?

Why is the no requirement to test the Gravity Xflow before first flight of the day?
There is still a need for it to be operational before dispatch.

One thing that always was a mystery for me, and which I never got explained,
Why does the powered xflow need to be off before take off?
What's the story behind this limitation?


Some one who could explain?

Thanks!

[Jumbo744]

Hey there, i'm sure you know that the reason why you put it to manual before takeoff is to prevent the system to automatically transfer fuel from one tank to the other in case it detected a fuel imbalance (200lbs). Now i guess if you line up and have a fuel imbalance of 200lbs already you have bigger problems. And why they don't want the system to correct the imbalance during takeoff, I don't know....

[galaxy flyer]

Transfer during critical regimes is to, one, isolate the tank-to-engine so any fuel problem doesn’t affect both engines and two, to ensure pilots don’t forget to the transfer is in progress and cause a greater opposite unbalance.

Testing most things only proves that the device worked that time and says little about the next time. Probably wear was more attributed to test8ng than actual use.