The US military plans to order 1,400 to 1,600 Raytheon GBU-49 Enhanced Paveway bombs in the fourth quarter to distribute to certain foreign customers of the Lockheed Martin F-35, according to an acquisition notice released on 30 April.

The notice from the Air Force Material Command (AFLCMC) appears only two months after Naval Air Systems Command (NAVAIR) revealed plans to acquire 400 more GBU-49 precision guided munitions for the US military’s own fleet of F-35s.

The GBU-49 is an enhanced version of the laser-only GBU-12. Both are 227kg (500lb) bombs, but the GBU-49 adds a GPS antenna for guidance.

In 2016, the Pentagon’s director for test and evaluation criticised the military’s plan to deploy the F-35As with GBU-12s, saying the weapon’s laser-only guidance system was of limited use for moving targets on the ground.

As an interim replacement, the F-35 joint programme office decided to use the GBU-49 to give F-35s fielded with Block 3F a capability to strike moving targets.

The latest acquisition notice expands the US military’s acquisition of GBU-49 to certain foreign partners that are already approved to acquire the weapon.

The notice itself serves as a required “sources sought” notification, allowing any competitors to offer alternatives to the GBU-49. Boeing also offers the 227kg-class GBU-54, but it’s not clear if the company will respond to the AFLCMC’s sources sought notice.

The AFLCMC suggests the GBU-49 might be its only option. Its goal in releasing the sources sought notice is to “confirm there are no other sources capable of meeting this requirement,” the documents states.

The requirement is for a 227kg-class bomb that is compatible with an F-35 using Block 3F software, and that can “consistently” hit moving targets traveling in a constant direction and at a constant speed up to 113km/h (70mph) and manoeuvring targets with speeds up to 64km/h.