Charles McGrath was born on December 16, 1948, in Maryland. He enlisted in the U.S. Air Force Reserve on January 6, 1970, and went on active duty on March 23, 1970. McGrath was trained as a Pararescueman and after completing Airborne School, Scuba Divers School, Medical Training, Mountain Climbing School, and the Pararescue Technician Course, he deployed to Southeast Asia in May 1971. He served with the 40th Aerospace Rescue and Recovery Squadron at Udorn Royal Thai AFB, Thailand, until being wounded in action in June 1972, during a mission for which he would later be awarded the Air Force Cross. Sgt McGrath continued in the Pararescue career field until 1979, when he received a commission in the Air Force and cross-trained into computer programming, serving at the Pentagon with the Unit Status and Identity Report System from January 1980 to June 1985. This system allowed the Joint Chiefs of Staff to monitor U.S. Military readiness. Capt McGrath's final assignment was as an analyst with United States Atlantic Command at Langley AFB, Virginia, where he served from June 1985 until his retirement from the Air Force on July 31, 1990.

His Air Force Cross Citation reads:

The President of the United States takes pleasure in presenting the Air Force Cross to Charles D. McGrath, Sergeant, U.S. Air Force, for extraordinary heroism in military operations against an opposing armed force as a Pararescueman on a HH-53C Rescue Helicopter of the 40th Aerospace Rescue and Recovery Squadron, Nakhon Phanom Royal Thai Air Base, Thailand, SEVENTH Air Force, in action in North Vietnam on 27 June 1972. On that date, while penetrating dense jungle to rescue a severely injured American airman, Sergeant McGrath exposed himself to intense ground fire in order to drag the incapacitated survivor to a suitable recovery area. Seeing his rescue aircraft crippled by the hostile fire, he directed air strikes against surrounding hostile ground forces until he was able to secure the survivor and himself to the penetrator of a backup helicopter. Rising through constant accurate ground fire, he shielded the survivor with his own body until they were successfully recovered into the aircraft where he immediately began providing the vital medical assistance required to save the lives of the survivor and an injured crew member. Through his extraordinary heroism, superb airmanship, and aggressiveness in the face of the enemy, Sergeant McGrath reflected the highest credit upon himself and the United States Air Force.