August 1969 9th Supply and Transport Battalion, 16 December 1966 – 23 August 1969 709th Maintenance Battalion, 26 January 1967 – 20 August 1969 9th Adjutant General Company, 30 December 1966 – 26 August 1969 9th Military Police Company, 19 December 1966 – 25 September 1969 335th Army Security Agency Company (a.k.a. "335th Radio Research Unit"), 12 January 1967 – 5 April 1971 99th Support Battalion, 1 October 1969 – 12 October 1970 493 Military Intelligence Detachment, 3/9th Inf Div, 19 December 1966 - 20 August 1970 One of the experimental units serving with the division was the 39th Cavalry Platoon (Air Cushion Vehicle) which used three of the specially designed hovercraft to patrol marshy terrain like the Plain of Reeds along the south Vietnamese/Cambodian border. Other experimental units were the 1st and 2nd Airboat Platoons, which operated Hurricane Aircat airboats. From 1967 on, one of the division's brigades (the 2d Brigade) was the Army contingent of the Mobile Riverine Force (MRF). This brigade lived on the ships of Navy Task Force 117, and were transported on their infantry missions throughout the Mekong Delta on Tango boats (converted landing craft) supported by various other armored boats. The MRF was often anchored near the South Vietnamese city of Mỹ Tho, or near the Division's Đồng Tâm Base Camp and they conducted operations in coordination with the Navy SEAL teams, the South Vietnamese Marines, units of the ARVN 7th Division and River Assault Groups. Following the Tet offensive in 1968, General Westmoreland stated that the Division and the MRF saved the Delta region from falling to the People's Army of Vietnam forces. In 1969, the division also operated throughout IV Corps. Chuck Hagel, former Secretary of Defense, served in the 9th ID from 1967 to 1968. Holding the rank of Sergeant (E-5), he served as an infantry squad leader. Hagel served in the same infantry squad as his younger brother Tom, and they are believed to be the only American siblings to do so during the Vietnam War. In the 1994 film Forrest Gump, the eponymous main character was a member of the 9th Infantry Division in Vietnam, notably: 4th Platoon, Company A, 2nd Battalion, 47th Infantry. The Division's major units departed South Vietnam on 27 August 1969 (HHC & 1st Brigade) to Hawaii; 27 August 1969 (2nd Brigade) to Fort Lewis, Washington; 12 October 1970 (3rd Brigade) to Fort Lewis. Post