Bald eagles produce a weak, stuttering call, usually written as a rapid series of chirps and whistles delivered from a perch or in flight. The sound carries poorly and does not match the visual weight of a bird with a wingspan approaching two metres.
Sound editors long ago substituted the drawn-out descending scream of the red-tailed hawk, a common and far more cinematic call. The swap is now so entrenched that many people identify the hawk's voice as the eagle's, and hear a genuine eagle recording as wrong.
What remains less settled is why the voice is so slight. Bald eagles are highly vocal at nests and roosts, so the calls clearly work at short range; the usual reading is that a bird which hunts by sight over open water has little use for long-distance advertisement. That is an interpretation rather than a measured result.