Wiktionary
vb. (present participle of power down English)
Usage examples of "powering down".
Kell saw the two A-wings powering down and was relieved he didn't have to remind them.
Hunter waited for his heart and breathing to slow down a little, then reached out a shaking hand and hit the disconnects, powering down the engines.
Wedge heard the hissing rumble as the factories inside went into standby mode, powering down and cooling off.
The fiery arc had vanished as quickly as it had come after Scotty ordered the powering down of control bus twenty-three.
As it approached, it slowed enough for him to see the bulging of the carbonsponging powering down over the long appendages in thick, rippling lines.
He turned and walked back down the corridor to the abandoned office and resumed his previous seat, powering down his infrared again to sit in the pitch-blackness.