A hydraulic leak that, along with inclement weather, forced a NetJets Citation on a ferry flight from Appleton, Wis., to Rochester, Minn., to divert to Minneapolis on January 12 was caused by a break in a hydraulic line, not by a bullet strike. During the post-flight inspection in Minneapolis a broken hydraulic line was found inside the left engine compartment, as well as a bullet hole on top of the right wing with the bullet still embedded. At press time authorities had not determined how long the .308-inch-diameter slug had been in the aircraft, but there is speculation that the airplane was hit by a descending bullet that had been fired into the air. The FBI has taken possession of the slug and is investigating.