You were only waiting
Three sounds — four, counting the blackbird dubbed in afterwards: Paul McCartney’s voice, his Martin acoustic, and a tapping that engineer Geoff Emerick spent years insisting was not a metronome but McCartney’s foot on the studio floor. “Blackbird” was cut solo in one evening at Abbey Road, 11 June 1968, and it never needed anything more.
The guitar figure is borrowed Bach: he and George Harrison had learned the Bourrée in E minor as teenagers to show off, and McCartney bent its shape into something of his own. The words, he has said, were aimed at something specific — the Black women of the American civil-rights struggle, “bird” being English slang for a girl, with Little Rock on his mind. In 2016 he met Thelma Mothershed Wair and Elizabeth Eckford, two of the nine students who integrated Little Rock Central High in 1957, and called them the inspiration for the song.
“Take these broken wings and learn to fly.” It was never just birdwatching.