WASHINGTON--The controversial F111 military airplane has been grounded for the fifth time in less than two years in the wake of a Nevada training crash which killed two pilots, including a former Viola, Ill. man.
  The Air Force announced it has grounded its fleet of 223 swingwing jets until it determines what caused the crash that killed Lt. Col. Thomas J. Mack, 38, son of Mr. and Mrs. Bert Mack of Viola, and Maj. James L. Anthony, 35, of Big Spring Tex.
  They went down with the $8 million plane Monday during a training mission at the bombing and gunnery range at Nellis Air Force Base, about 45 miles northwest of Las Vegas.
  After Air Force problems with the F111, a contract for a Navy version was canceled last year and a contract for an Air Force bomber version was sharply curtailed.
  Development of the F111 began under former Secretary of Defense Robert S. McNamara seven years ago. Since then a fleet of the airplanes has been used in Vietnam, then recalled.
  The most recent grounding of F111A jets occurred last month and affected 89 Air Force planes. The air force said suspension was a result of a heat-duct leak in two aircraft and one engine undergoing ground test. Trouble developed earlier in the plane's wing structure and hydraulic system.
  The plane originally was designed to serve both the Air Force and the Navy as bombers and fighters. The body of Col. Mack will be taken to Chicago for funeral services.
He was born near Preemption. He was a 1949 graduate of Winola High School and attended St. Ambrose College, Davenport, two years. He entered the Air Force in 1951. He had served in that branch of the military since then. He was graduated from the University of Utah.
  Col. Mack was a member of the 47th Tactical Air Command Fighter Wing Squadron.
  On March 21, 1959 he married Linda Nelson of Chicago in Chicago.
Survivors include his wife; daughters, Kelly, 10, and Karen, 6; a son, Keith, 8; his parents; a grandmother, Emma Jordon, Viola; sisters, Mrs. Maurice Conner, Canton, Ill., and Jeanne Mack, Wyoming, Ill.; brothers, Gerald, Santa Ana, Calif., and James, Torrance, Calif.
(Rock Island Argus - January 1970)