Given this, "descending 3 top" could easily be a misremembered version of "descending 3:1 rule to the Top of Descent." It's plausible that a user heard this phrase in a flight simulation or aviation video and later attempted to search for it.
She stepped into the lobby as the 3 Top doors opened. Inside, a man in a navy suit and a face like a closed ledger entered, phone pressed to ear. A young woman with bright red headphones spun toward the glass, absorbed. The elevator carried them down with the soft sigh of machinery; Sata felt the motion as a change in the building’s breath. sata jones in descending 3 top