The following is the Aug. 23, 2018 Congressional Research Service report, Air Force OA-X Light Attack Aircraft Program.
From the report:
On August 6, 2018, the U.S. Air Force issued a presolicitation notice declaring its intent to acquire a new type of aircraft. The OA-X light attack aircraft is a small, two-seat turboprop airplane designed for operation in relatively permissive environments. The announcement of a formal program follows a series of Air Force “experiments” to determine the utility of such an aircraft.
Why Light Attack?
In a number of venues during 2018, Air Force Secretary Heather Wilson expressed the purpose of a new light attack aircraft as giving the Air Force an ability to free up more sophisticated and expensive assets for other tasks, citing the example of using high-end F-22 jets to destroy a drug laboratory in Afghanistan as an inefficient use of resources. Per-hour operating costs for light attack aircraft are typically about 2%-4% those of advanced fighters. She and other officials have also noted that the 2018 National Defense Strategy put a greater emphasis on potential conflicts against capably armed nation-states, further stressing a need to minimize the use of high-end assets in other types of conflict. (For more on that document, see CRS Insight IN10855, The 2018 National Defense Strategy, by Kathleen J. McInnis.) Conversely, Former Secretary of Defense Robert Gates had criticized the Air Force as focusing excessively on the kind of high-end, near-peer conflicts in that strategy; the light attack aircraft can be seen as making the Air Force more relevant to low-end and counterinsurgency warfare.