Pacific Air Lines Flight 773

Pacific Air Lines Flight 773 was a Fairchild F27A Friendship airliner that crashed at 6:49 a.m. on May 7, 1964, near Danville, California. The crash was most likely 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.
This crash is relatively similar to Pacific Southwest Airlines Flight 1771, which happened under the same circumstances.

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