During World War II, a project called Project Pigeon was developed to utilize pigeons in guiding missiles. Since pigeons lack hands and therefore cannot pilot missiles like humans pilot planes, B. F. Skinner, the designer of the project, focused on their natural ability to peck at objects.

The core of Project Pigeon was a pigeon-sized cockpit named the “Pelican” that was placed at the front of the missile. Although it didn’t resemble a pelican’s beak, Skinner chose this name because of the saying that pelicans can hold more in their beak than their belly. The Pelican contained a screen that projected an image of the target the missile needed to hit.

When a pigeon was placed inside the Pelican, it was secured in place and trained to peck at the screen. Cables attached to the pigeon’s head would help guide the missile based on its pecking behavior. If the pigeon pecked at the center of the screen, the missile would fly straight. If the pigeon didn’t peck at the center, the cables would adjust the missile’s trajectory until the pigeon started pecking at the center of the projected image.

As Skinner continued to develop Project Pigeon, he discovered that using three pigeons instead of one improved the system. This was because even a momentary pause or mistake by a single pigeon could cause the missile to veer dangerously off course. By having two co-pilots for the pigeon and implementing a “net signal” produced by all three, potential errors were greatly reduced.