All of the nouns in the sentence are safety, passengers, concern William J. Snow, pilot, and TWA.
The common nouns are safety, passengers, concern, and pilot.
The proper nouns are William J. Snow and TWA, the name of a person and the name of a company.
The word pilot is a common concrete noun.
jack-o-lanter, jelly, jeans, jack, jam, jazz, job, jock
Lisa Scott on Halloween Safety Concerns
CyberKnife Safety Concerns
Joseph Maroon Talks About Safety Concerns for Resveratrol
Safety Concerns of Sunscreen