The little family wasn't found until the rescued pilot was already at the naval hospital. They were hiding in the plane's rear hatch and were taken to the mess hall for warm milk.
In 1945, a Coast Guard plane took off from San Diego to rescue a Navy pilot downed at sea. The crew completed the rescue and returned to base, only to discover three unexpected passengers: a cat named Salty and her two kittens.
The cats had stowed away without anyone noticing and spent the whole mission hiding aboard the plane.