AGM-158B是聯合空對地的戰區外匿蹤巡弋飛彈，而AGM-158C型是反艦型的。
過去這個增程型被稱呼AGM-158D或者EX，據說攻擊距離高達1000nm，約1800公里。
Lockheed Martin set to commence JASSM AGM-158B-2 LRIP
by Robin Hughes
The US Air Force Life Cycle Management Centre (AFLCMC) has awarded Lockheed Martin Missiles and Fire Control a USD428.4 million contract for Lot 19 production of the Joint Air-to-Surface Standoff Missile – Extended Range (JASSM-ER) precision standoff missile for the US Air Force (USAF).
Announced by the US Department of Defense on 22 January, the contract provides for 400 JASSM-ER missiles, work on which is expected to be completed by July 2025. The Lot 19 award also paves the way for a future production cut-in modification to facilitate low-rate initial production (LRIP) of 40 AGM-158B-2 ‘extreme-range’ variant JASSMs, previously referred to as JASSM-XR or AGM-158D.
Lockheed Martin declined to comment specifically on the AGM-158B-2 development, but told Janes, “Lockheed Martin and the US Air Force continue to test upgraded subsystems and plan to qualify the new parts to be put into the next JASSM-ER variant at a later production cut-in date.”
In September 2018 the AFLCMC awarded Lockheed Martin a USD51 million contract “to undertake all-up round-level systems engineering and programmatic activities to align and phase work necessary to design, develop, integrate, test, and verify component and subsystem design changes to the JASSM-XR baseline electronics, hardware, firmware, and operational flight software”. The contract also provided for “preparation for final all-up round integration, system-level ground and flight testing, qualification, and incorporation into a future production baseline engineering change proposal”. In parallel, the company was charged with maturing a new missile control unit and necessary hardware and infrastructure “to support future JASSM-XR production cut-in”. Work on the contract is scheduled for completion in July 2023.
