"Pacific Air Lines Flight 773 was a Fairchild F27A Friendship airliner that crashed at 6:49 a.m. on May 7, 1964, near San Ramon, California, USA. The crash was probably the first instance in the United States of an airliner's pilots being shot by a passenger as part of a mass murder/suicide. Francisco Paula Gonzales, 27, shot both the pilot and co-pilot before turning the gun on himself, causing the plane to crash and killing all 44 aboard.

A former member of the Philippine sailing team at the 1960 Summer Olympics, Gonzales, a warehouse worker living in San Francisco, had been "disturbed and depressed" over marital and financial difficulties in the months preceding the crash. Gonzales was deeply in debt and nearly half of his income was committed to various loan payments, and he had advised both relatives and friends that he "would die on either Wednesday, the 6th of May, or Thursday, the 7th of May." In the week preceding the crash, Gonzales referred to his impending death on a daily basis, and purchased a Smith & Wesson Model 27 revolver through a friend of a friend, with serial number S201645. The evening before the crash, before boarding a flight to Reno, Nevada, he had shown the gun to numerous friends at the airport and told one person that he intended to shoot himself. Gonzales gambled in Reno the night before the fatal flight and told a casino employee that he didn't care how much he lost because "it won't make any difference after tomorrow.""