Software problems discovered during testing have caused delays for the updated extended-range variant of the missile, according to the Government Accountability Office's annual review of the Pentagon's $2.4 trillion weapons portfolio. The program also "continues to experience production delays," the GAO added.

The GAO report did not disclose the amount of payments withheld. Navy officials reported that a successful flight test in December has given them confidence that the missile can achieve operational readiness by September 2026, which is over two years past the original July 2024 target, according to the GAO.

The upgraded missile, known as the AARGM-ER, is built to be fired from Navy and Marine Corps planes to neutralize enemy air defenses. Its extended range allows electronic-warfare aircraft to engage air-defense radar from greater distances. The program's delays have raised concerns about readiness in the Indo-Pacific region, where China has heavily invested in advanced air-defense systems. The missile is expected to be a key asset in any future conflict, providing a critical ability to destroy radar sites without putting crews at excessive risk.

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The program was initiated in 2017, with development beginning in March 2019. This upgraded missile is critical in a potential conflict with China, as it increases the distance from which U.S. electronic-warfare aircraft can engage air-defense radar.

The AARGM-ER is designed to be compatible with several Navy and Marine Corps platforms, including the F/A-18 Super Hornet and the F-35 Lightning II. The Navy has designated this missile as a priority program for the Indo-Pacific region, where China's advanced radar systems pose a significant threat.

The AARGM-ER is an evolution of the AGM-88E AARGM, which has been in service and combat-proven for years. The extended-range variant incorporates a new rocket motor and control section, significantly increasing its reach. This upgrade is crucial for the Navy's strategy in the Indo-Pacific, where vast distances and dense enemy air defenses demand longer standoff capabilities. Development delays are not uncommon for complex weapons, and the program remains a high priority for the Pentagon.

During a May 28 investor conference, Northrop CEO Kathy Warden said the missile is "coming out of development."

The earlier AGM-88E AARGM has been used successfully in multiple combat operations, destroying radar sites while keeping pilots safe. The new AARGM-ER builds directly on that proven technology, adding a larger motor and improved guidance to nearly double the missile's range. That extra reach is seen as essential for penetrating China's layered air-defense network, where long-range surface-to-air missiles can threaten aircraft from hundreds of miles away. Without the extended-range variant, U.S. electronic-warfare planes would have to fly closer to hostile radar, increasing risk to aircrews.

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