For example, take N133AA.
https://www.jetphotos.com/registration/N133AA shows American Airlines photos from the 90s and an helicopter from this decade:
The FAA only shows the helicopter registry:
Transtats shows that the last time N133AA flew from LA to NY was in 2008, and I'd bet that was not the helicopter.
Is it normal that tail numbers get reused? How can I make my cross-searches reliable?