David Hensel was born on November 15, 1947, in Pittsburgh, Pennsylvania. He enlisted in the U.S. Army on March 6, 1969, and after completing basic training and advanced individual training as an infantryman, Hensel was sent to Southeast Asia. He served with B Company, 1st Battalion (Mechanized), 5th Infantry Regiment, 25th Infantry Division in the Republic of Vietnam from January 1970 until he was killed in action in Cambodia on May 16, 1970.

His Bronze Star Medal Citation reads:

For distinguishing himself by outstanding meritorious service in connection with ground operations against a hostile force in the Republic of Vietnam during the period 5 January 1970 to 16 May 1970. Through his untiring efforts and professional ability, he consistently obtained outstanding results. He was quick to grasp the implications of new problems with which he was faced as a result of the ever changing situations inherent in a counterinsurgency operation and to find ways and means to solve those problems. The energetic application of his extensive knowledge has materially contributed to the efforts of the United States mission to the Republic of Vietnam to assist that country in ridding itself of the Communist threat to its freedom. His initiative, zeal, sound judgement and devotion to duty have been in the highest tradition of the United States Army and reflect great credit on himself, his unit and the military service.