I am planning to install a T fitting on the IN side of each of my two
Facet fuel pumps and run a short crossover aluminum line connecting the
these two fittings. The purpose here is to provide a connection between
the two wing tanks so that if one pump fails, the other will continue to
pull fuel from both wings.

I believe that some of you have installed a ball valve in this line so
that if for any reason one wing tank needed to be drained, the other
tank would be isolated. My inclination would be to leave this valve
normally open so that each pump would be feeding the header tank from
both wings at all times. Do any of you see a problem here?

Question: Is there any benefit to having this ball valve readily
accessible in flight from the cockpit?

Happy Holidays!

Angier Ames