His shadow swung like an irregular pendulum across the pavement, describing the course of a soundless battle: it was a man fighting himself to enter that door or to escape.
In the deep blue above it, the stranger’s plane was a single spark changing color and flashing from side to side, like the tip of a pendulum swinging in the darkness, beating time.
Flung from side to side, like a battered pendulum, clinging to the wheel, half in her seat, half on her knees, she fought to pull the ship into a glide, for an attempt to make a belly-landing, while the green ground was whirling about her, sweeping above her, then below, its spiral coils coming closer.
There are no more uses of "pendulum" in the book.
Show samples from other sources
The clock uses a pendulum to keep time.
Now the pendulum has swung the other direction and voters are demanding...