The Afghan Air Force could receive four more Embraer A-29 light attack turboprop aircraft, adding to 20 already on contract, the US Air Force says in a new contracting notice.

The four aircraft would be assembled by Embraer at the company’s Jacksonville, Florida, facility, but the prime contractor could change.

Sierra Nevada teamed with Embraer to win the original bidding contest with Hawker Beechcraft, which is now part of Textron Aviation.

The USAF is considering other sources to procure up to four A-29s from Embraer for delivery to the Afghan Air Force, according to a “sources sought” notice posted on 6 October.

Sierra Nevada remains on contract to maintain the Afghan air force A-29 fleet to a mission capability rate of 80%, so any new prime contractor must continue working with the Sparks, Nevada-based company.

The A-29 acquisition emerged from a USAF programme called “building partnership capacity”. The programme allows the USAF to procure A-29s and other specialised equipment on behalf of other countries that lack the budget and administrative resources to acquire sophisticated light attack aircraft on their own.

The USAF has acquired 20 A-29s for the Afghan Air Force, of which at least eight have been delivered. As the A-29 is now a US weapon system, it was eligible to be procured in the Foreign Military Sale process. Last year, Lebanon selected the US-assembled A-29 as a close air support aircraft, with Sierra Nevada as the prime contractor.

Embraer also produces the A-29 assembled in Brazil for other customers.