Northrop Grumman has received an Air Force contract to develop a new ground attack weapon for the F-35 Lightning II stealth fighter, reports the defense firm.

On Thursday, Northrop Grumman said it had received a $2 million contract with follow-on options to develop the Stand-in Attack Weapon (SiAW) missile. The deal has a three-month period of performance, with three competitive gates for three prime contractors to validate their capabilities.

Under the first phase, the Air Force...