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Related Video Above: What Role Would 5th Generation Stealthy Fighter Jets Play in a War with China?

*A Top Warrior Maven Story - republished for viewer interest 

By Kris Osborn - President & Editor-In-Chief, Warrior Maven

The anticipated timeline for a massive “software drop” Block IV upgrade to the F-35 Joint Strike Fighter, may be impacting the Air Force’s decision to slow F-35A procurement, according to a newly released report on the future fighter force by The Mitchell Institute for Aerospace Studies. 

The report says that delays in the delivery of Block IV to 2029 are potentially impacting the service’s delivery and acquisition plans for the aircraft.

“Block 4 is a suite of mostly classified hardware upgrades, technologies, and software drops that radically enhances F-35 combat effectiveness. The F-35 was planned and produced around a concept of spiraling more capabilities into production aircraft,” the Mitchell Study states.


F-35 Weapon Loads

Many of the JSF’s combat capabilities are of course woven into developmental software increments or “drops,” each designed to advance the platform’s technical abilities. There are more than 10 million individual lines of code in the JSF system.

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The now operational Block 3F F-35 software drop, increased the weapons delivery capacity of the JSF as well, giving it the ability to drop a Small Diameter Bomb, 500-pound JDAM (Joint Direct Attack Munition) and AIM-9X short-range air-to-air missile. The AIM-9X is an Air Force and Navy heat-seeking infrared missile.

F-35 Block IV "Software Drop"

Delays with Block IV certainly run counter to the Air Force’s fast-evolving software upgrade process, as upgrades are accelerating and integrating on much faster timelines to leverage technological advances. 

Air Force leaders have repeatedly explained that software modernization will no longer take place within spread apart, predetermined drop windows often spread apart by a year or more, but rather happen on a more continuous, flowing or “as-ready” kind of basis. 

This kind of strategy complements the broader software drop trajectory and expedites modernization, security patches, AI-enabled functionality, condition-based maintenance and, perhaps of greatest significance, weapons upgrades.

Due to some of the more recent software Block drops, the F-35 can fire the AIM-9X “off bore-sight” and a growing range of other weapons. Now, the Block IV will in the next few years enable the stealth fighter to drop the emerging Small Diameter Bomb II, called Stormbreaker.


An F-35A from the 62nd Fighter Squadron at Luke Air Force Base flies an aerial mission

Given the importance of quickly spiraling in new software to expand weapons and combat functionality, the Mitchell report cites concerns related to the timeline for Block IV arrival. Block IV, the report says, will be needed in any kind of confrontation with China.

Operational analysis has indicated that the even-more-advanced Block 4 configuration is necessary to be effective in a conflict with China. However, challenges with maturing all of the Block 4 technologies has slid delivery of the full Block IV suite to at least 2029, and this is a significant factor in the Air Force's decision to slow F-35A procurement,” the Mitchell report states.

Kris Osborn is the defense editor for the National Interest and President of Warrior Maven -the Center for Military Modernization. Osborn previously served at the Pentagon as a Highly Qualified Expert with the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University.

Kris Osborn, Warrior Maven President

Kris Osborn, Warrior Maven President, Center for Military Modernization