Originally Posted by
Denti
Draining potable water is normal procedure on our planes here in germany in winter. Kinda dangerous during the walkaround next morning on the huge ice patch below the tail of the plane...
Not sure on airliners, but modern business jets have the ability to purge the water lines while in flight. That minimizes the skating rink on the ramp.
In addition, any liquid needs to be given consideration...Perrier, cans of Coke, bottles of Champaign, etc.
My AFM has a chart that shows outside air temp vs. hours on the ground.
Follow the two selected columns to your answer of how often you must run the Aux Power Unit/Cabin heaters to preclude water system freezing. A heated hangar simplifies the whole process, but some places do not offer such luxuries.