Lockheed Martin F-35 Lightning II

The F-35 Lightning II emerged from the U.S. Department of Defense's Joint Strike Fighter program, which was developed in the 1990s to produce a family of next-generation strike fighters for multiple military branches while maximizing commonality in airframe, engine, and avionics components.[3] The program of record consists of 2,456 production aircraft; the Department of Defense plans to purchase 2,470 aircraft in total and estimates development and production costs of at least $485.2 billion.[2]

Nineteen governments had agreed to purchase F-35 aircraft as of the Congressional Research Service's November 2024 research.[2] For Israel, the F-35I was expected to improve operations in areas protected by advanced surface-to-air missiles and enable the aircraft to build its own intelligence picture.[6]

The aircraft's fifth-generation features include stealth shaping and radar-absorbent coatings, an internal weapons bay, composite materials, active electronically scanned array radar, 360-degree visible-light and infrared sensors, sensor fusion that merges data from multiple onboard systems into a single picture, and the ability to fly supersonically without an afterburner for limited periods.[2][6] These attributes combine offensive capability with enhanced survivability.

The F-35 originated in the U.S. Department of Defense's Joint Advanced Strike Technology program, launched in late 1993 in response to the Bottom-Up Review of American defense policy.[3] The program was designed to replace several aging-aircraft programs, including the Navy's A-12/AFX and the Air Force's multirole fighter intended to succeed the F-16. In 1995, an advanced DARPA short-takeoff-and-vertical-landing project was folded into the effort, opening participation to the U.S. Marine Corps and the British Royal Navy; the program was subsequently renamed the Joint Strike Fighter.[3]

On November 16, 1996, the Department of Defense selected Boeing and Lockheed Martin to compete in the concept-demonstration phase.[3] On October 26, 2001, the Lockheed Martin-led team was chosen to develop and produce the Joint Strike Fighter family.[3] The design sought to maximize commonality among the three variants in airframe, engine, and avionics components to reduce production, operating, and support costs.[3] The planned primary engine was the Pratt & Whitney F135, derived from the F-22A's F119, while the General Electric F136 was established as an alternative intended to compete for production and sustainment contracts.[3]

The program envisioned three variants built on a common platform.[3] The F-35A was the conventional-takeoff-and-landing aircraft primarily for the U.S. Air Force, intended to replace F-16s and A-10s. The F-35B was a short-takeoff-and-vertical-landing design for the U.S. Marine Corps and British Royal Navy, replacing Harrier aircraft and using a shaft-driven lift fan connected to the main engine together with thrust-vectoring nozzles. The F-35C was the carrier-capable variant, featuring strengthened landing gear and airframe, an arresting hook, and folding wingtips for the U.S. Navy. Projected component commonality across the three variants ranged from 70 to 90 percent in production cost.[3]

The planned weapons configuration for all three variants included two internally mounted 2,000-pound weapons, AIM-120 AMRAAM air-to-air missiles with an approximate range of 26 nautical miles depending on altitude, and a 25-millimeter cannon of the type used on the AV-8B Harrier.[3] Primary weapons are carried internally to preserve the aircraft's low radar signature; additional weapons can be carried externally when stealth is less critical.[2]

All three F-35 variants are single-seat aircraft sharing advanced stealth characteristics, common weapons and avionics, and the same basic engine.[2] They can reach speeds of up to Mach 1.6 and have combat radii ranging from 450 to 600 nautical miles.[2] Stated roles include strategic attack, suppression and destruction of enemy air defenses, offensive and defensive counter-air operations, anti-surface warfare, strike coordination and reconnaissance, and close air support.[2]

The F-35A, the conventional-takeoff-and-landing variant, accounts for 1,763 of the 2,456 aircraft in the program of record and is primarily assigned to the Air Force.[2] The F-35B, the Marine Corps's short-takeoff-and-vertical-landing variant, uses a swiveling rear exhaust nozzle and a mid-fuselage lift fan; the Marine Corps plans to procure 353 F-35Bs.[2] The F-35C, the carrier-suitable variant, is distinguished by its strengthened airframe, arresting hook, and folding wingtips; the Navy plans to procure 273 F-35Cs, with the Marine Corps adding 67 more.[2]

The aircraft is also designed to function as a node in a networked combat environment, providing sensor fusion, interoperability in contested environments, and enhanced situational awareness to other platforms and commanders.[2] Its Autonomic Logistics Information System was designed to monitor aircraft health and manage maintenance automatically, but it experienced labor-intensive data entry, cybersecurity vulnerabilities, and incorrect results. The Joint Program Office has been transitioning to the cloud-based Operational Data Integrated Network to address those shortcomings.[2]

The F-35 program accumulated significant cost growth from its earliest stages. The December 2005 Selected Acquisition Report estimated total program cost at $276.5 billion in then-year dollars for 2,458 aircraft, a program unit acquisition cost of $112.4 million per aircraft and an average procurement unit cost of $94.8 million.[3] The report noted that the program had breached a Nunn-McCurdy cost-growth limit, with unit-cost growth exceeding 30 percent of the original Acquisition Program Baseline.[3] By the time of the Congressional Research Service's 2014 reporting, the Pentagon planned to spend $391.2 billion on 2,443 U.S. aircraft, and the later CRS estimate stood at no less than $485.2 billion.[2][7]

More than $45 billion in cost growth from the September 2003 baseline was attributed primarily to a one-year extension of the System Development and Demonstration phase, a corresponding procurement delay, revised quantity profiles, labor and overhead rates, and weight-growth problems in the F-35B.[3] The F-35B was identified as the most technologically challenging variant, a major cost driver, and a source of persistent weight-growth difficulties; some analysts proposed canceling it in favor of the carrier variant, while Air Force and Navy civilian leaders supported retaining it.[3]

Full-rate production was approved on March 12, 2024, 23 years after the Joint Strike Fighter development program began, and testing was completed after 990 aircraft had already been built.[2] The aircraft entered initial operational test and evaluation with 873 unresolved deficiencies, including 13 Category 1 deficiencies affecting safety or combat capability.[2] Delays in the Joint Simulation Environment contributed to the timing of the full-rate-production decision.[2]

The Block 4 modernization effort and associated Technical Refresh 3 hardware upgrade are intended to add more than 50 software improvements, enhanced sensors and electronic-warfare systems, long-range precision weapons, and greater data fusion.[2] Block 4 costs rose from an estimated $10.6 billion in 2018 to $16.5 billion by 2023, while many new capabilities were expected to remain unavailable until the 2030s.[2] The Air Force halted acceptance of F-35A deliveries in July 2023 because the TR-3 software was incomplete; deliveries resumed in July 2024 with limited TR-3 capability.[2]

Sustainment is a major long-term challenge. Maintaining the F-35 fleet through 2088 was estimated to cost approximately $1.58 trillion, up from $1.1 trillion in 2018.[2] Fleet readiness in 2023 fell short of service targets across all three variants: the mission-capable rate was 51.9 percent for the F-35A, 59.7 percent for the F-35B, and 61.9 percent for the F-35C, compared with minimum targets of 80 percent for the Air Force variant and 75 percent for the Navy and Marine Corps variants.[2]

Eight countries participated in the F-35's system-development, demonstration, and production phases: the United Kingdom, Canada, Denmark, the Netherlands, Norway, Italy, Turkey, and Australia.[2] Together these partners pledged approximately $4.5 billion to help defray development and production costs, encourage future exports, and stimulate the international market.[3] The United States revoked Turkey's participation in 2019 after Turkey acquired and intended to field the Russian S-400 air-defense system.[2]

The United Kingdom emerged as the program's second-largest partner, supplying 15 percent of its parts.[8] More than 500 British businesses employing thousands of workers contributed to the program, and UK-produced components formed part of a global supply chain serving at least nine countries, including Israel.[8] Israel and Singapore participated as Security Cooperative Participants rather than full development partners, with each believed to have contributed approximately $50 million to the program.[3]

As of the Congressional Research Service's November 2024 research, nineteen governments had agreed to purchase F-35 aircraft.[2] The U.S. program of record assigned 1,763 F-35As to the Air Force, 353 F-35Bs to the Marine Corps, 273 F-35Cs to the Navy, and 67 F-35Cs to the Marine Corps.[2] Israel's planned fleet of 75 aircraft, based on the conventional F-35A configuration, made it a significant international operator by fleet size and operational record.

The United States and Israel signed an agreement in February 2003 to cooperate in the development of the F-35 Joint Strike Fighter, with Israel joining as a security-cooperation participant rather than a full cooperative-development partner.[9] Under that arrangement, Israel cannot assign personnel to the F-35 Joint Program Office, does not receive full technical briefings, and cannot independently alter the aircraft's core software code.[9]

Israel began the formal acquisition process in 2008.[6] In October 2010, Israel signed a $2.75 billion agreement with the United States to purchase 19 F-35 aircraft, with options for as many as 75.[9] The agreement also supported the integration of Israeli-specific electronic-warfare systems.[9] By December 2016, two batches totaling 33 aircraft had been ordered, and a further request authorized by Israel's security cabinet was expected to bring the total to 50. The 33-aircraft purchase was priced at $5.57 billion, including aircraft, spare parts, and simulators, and financed through U.S. security assistance.[6]

Israel's aircraft are designated the F-35I and bear the Hebrew name Adir — "Mighty One."[1] The Israeli variant uses the conventional F-35A configuration and includes a custom open-architecture layer intended to support Israeli electronic-warfare and indigenous-weapons updates.[2] An Israeli government-affiliated account also claims that Israel received U.S. permission to install its own software and integrate Israeli communications and fire-control systems.[10] INSS reported that Israel received most, if not all, of its demands concerning software control and indigenous-system integration, although whether it received full access to the source code remained unclear.[6]

The Adir's capabilities include a low radar cross-section, active electronically scanned array radar, 360-degree visible-light and infrared sensors, sensor fusion, a helmet-mounted display, and a logistics system that monitors aircraft health, detects faults, issues repair instructions, and can automatically order spare parts.[6] These features were expected to improve Israeli operations in areas protected by advanced surface-to-air missile batteries and allow the aircraft to generate its own intelligence picture independently of ground-based systems.[6]

Israel's role in the F-35 program extends beyond procurement: Israeli defense industries contribute components and systems to the global production line.[11] Israel Aerospace Industries manufactures F-35 wings at its facility in Lod, while an Elbit Systems subsidiary manufactures the aircraft's helmet.[6] Elbit Systems-Cyclone also produces center-fuselage composite components.[11]

Under the original government agreement, Lockheed Martin and engine manufacturer Pratt & Whitney committed to involving Israeli industry in producing F-35 aircraft sold to U.S. forces and other countries, meaning Israeli factories supply components for the broader international fleet.[12] In April 2025, the Pentagon announced two contracts with Lockheed Martin related to Israel, together valued at approximately $26.8 million, covering software development and integration for the F-35 Joint Strike Fighter and reflecting Israel's rights as a security-cooperation participant to contribute to the aircraft's design and configuration.[13]

Israel's Defense Procurement Directorate also signed a contract with Cyclone, a wholly owned Elbit Systems subsidiary, to develop and integrate an extended-range capability for the Adir.[14] Valued at more than $34 million, the contract covers external fuel tanks based on a Cyclone design originally developed for the F-16.[14] The capability is intended to extend the Adir's operational range, reduce reliance on aerial refueling, and increase flexibility during long-range missions.[14]

The first two Israeli F-35I aircraft landed at Nevatim Air Base in December 2016, officially becoming Israeli government property upon touching down after being flown from the United States by American pilots.[15] By December 2017, after receiving nine aircraft, the Israeli Air Force had declared its F-35 fleet operational; those jets were operated by the Golden Eagle Squadron at Nevatim.[1]

Fleet growth continued over the following years. Israel created a second F-35 squadron in 2020.[16] On January 18, 2026, three additional F-35I aircraft landed at Nevatim, bringing Israel's inventory to 48 of the 50 aircraft in its initial order; those jets joined the 116th and 140th Squadrons.[1] The two remaining aircraft from the initial order were still expected.[1]

In June 2024, Israel's Ministry of Defense signed a Letter of Offer and Acceptance for 25 additional F-35 aircraft — a $3 billion transaction funded through U.S. Foreign Military Financing and sufficient to equip a third squadron.[12] Deliveries were scheduled to begin in 2028 at a rate of three to five aircraft per year, with delivery of all 25 potentially extending to 2036 and the total fleet expanding to 75 aircraft.[12][17]

In May 2026, Israel's Ministerial Committee on Procurement approved a plan to acquire a fourth F-35 squadron from Lockheed Martin alongside a second F-15IA squadron from Boeing.[5] The ministry described the combined procurement as part of a decade-long force-buildup plan with a dedicated budget of 350 billion NIS and stated that the agreements would include full fleet integration, sustainment, spare parts, and logistics support.[5] Following the approval, the ministry directed its mission to the United States to begin finalizing agreements with American government and military counterparts.[5]

In May 2018, Israeli Air Force commander Maj. Gen. Amikam Norkin said Israel had used the F-35I in combat on two occasions and was the first country to attack with the F-35 in the Middle East.[4] "We are flying the F-35 all over the Middle East," Norkin said. "It has become part of our operational capabilities. We are the first to attack using the F-35 in the Middle East and have already attacked twice on different fronts."[4] The first-use assertion is therefore presented as an official Israeli claim.

FDD reported that Israeli F-35s struck Iranian targets in Syria in 2018 and shot down Iranian drones over Syria in 2021.[16] In 2023, an Israeli F-35I downed a cruise missile believed to have been launched from Yemen by the Houthis; the interception was described as believed to be the first time an F-35 had destroyed a cruise missile.[16] These reported engagements encompassed strike, drone-interception, and missile-interception missions.

Norkin's statement that Israeli F-35s were flying "all over the Middle East" indicated the aircraft's role in Israel's regional operations.[4] The extended-range capability being developed by Elbit Systems-Cyclone uses external fuel tanks based on an existing F-16 design and is intended to reduce reliance on aerial refueling during long-range missions.[14]

The F-35 program has been contested on multiple fronts since its inception. Cost growth has been the most persistent critique: the program breached a Nunn-McCurdy unit-cost limit as early as 2005, and total development and production estimates grew from $276.5 billion in 2005 to at least $485.2 billion by the mid-2020s.[2][3] The F-35B was singled out in early program reviews as the most technologically challenging design and a major cost driver, prompting proposals — ultimately rejected — to cancel it in favor of the carrier variant.[3] Block 4 modernization costs rose from an estimated $10.6 billion in 2018 to $16.5 billion in 2023, while many capabilities were pushed to the 2030s.[2]

Readiness shortfalls have drawn congressional scrutiny. Mission-capable rates in 2023 stood at 51.9 percent for the F-35A, 59.7 percent for the F-35B, and 61.9 percent for the F-35C, below the respective 80 and 75 percent service targets.[2] The logistical software system designed to underpin fleet readiness experienced cybersecurity vulnerabilities, labor-intensive data management, and erroneous outputs before a transition to a cloud-based replacement began.[2]

Israel's software rights and modification authorities have also been described differently by the sources. The Congressional Research Service account cited by Jewish Virtual Library states that Israel cannot independently alter the F-35's core software code, while an Israeli government-affiliated source claims that Israel received permission to install its own software.[9][10] INSS reported that Israel received most, if not all, of its demands for software control and indigenous-system integration, but said it was unknown whether Israel received full source-code access.[6]

In September 2024, the UK government suspended 30 export licenses to Israel while retaining the license for the F-35 program.[8] In May 2025, the UK High Court heard a challenge concerning the government's refusal to suspend export licenses for British-produced F-35 components, part of a broader controversy over UK arms transfers to Israel.[8]