The 1st and 2d Aviation Engineer Battalions were activated in May 1942 as Fleet Marine Force troops attached to IMAC. Lightly equipped, their three companies were intended to be airlifted onto islands to repair captured airfields. With no opportunities to be employed as such and the availability of Naval construction battalions for airfield rehabilitation and construction, they were provided with heavier equipment and re-designated "Separate Engineer Battalions," to differentiate them from the 1st and 2d {Divisional} Engineer Battalions, on 1 May 1944, the 1st and 2d Separate Engineer Battalions were then attached to III AC and VC, respectively. The battalions received a topographic company (Company D) in late 1944, but these were made separate companies in February 1945.

Bn    Activated                                  Deactivated
1st    1 May 1942 at New River         20 Aug 1946 Camp Pendleton
2nd   8 May 1942 Camp Elliot            6 Feb 1946 Camp Pendleton

• Aiken, Luther L, Cpl, (1943-1946)

• Barto, Earl Howard, Cpl, (1942-1944)

• Blankenburg, John Andrew, Sgt, (1942-1950)

• Blasiol, Victor, Sgt, (1941-1946)

• Collins, Theodore, Sgt, (1942-1945)

• Elliott, Richard Morrow, LtCol, (1940-1963)

• Gaffney, Thomas, Cpl, (1944-1958)

• Girman, Walter Elmer, PFC, (1942-1945)

• Harper, James Austin, Col, (1943-1963)

• Jarvis, John Francis, MSgt, (1941-1945)

• Jarvis, John, MTSgt, (1941-1945)

• Jarvis, Jr, John F, MSgt, (1941-1945)

• Jones, Jack C, Sgt, (1941-1953)

• McCrorie, James J, Cpl, (1945-1952)

• Milardovich, George Martin, WO, (1939-1946)

• Montana, Jr., Frank, PFC, (1944-1946)

• Pearson, Max, PFC, (1943-1946)

• Putman, James E., Sgt, (1943-1951)

• Shawaryn, Eugene Timothy, Sgt, (1940-1946)

• Smith, Richard, Sgt, (1954-1962)

• Unger, Werner R, Cpl, (1939-1945)

• Zalewski, William John, MGySgt, (1939-1967)