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Aircraft · Air

F-35B Lightning II

Short takeoff and vertical landing variant of the F-35 stealth multirole fighter.

Part of the F-35 Lightning II program →

by Lockheed Martin · First fielded 2015

FieldedAircraftAirCombat useSep 27, 2018
Milestones20082018
  1. First flightF-35B completes first flight, confirmed
  2. ExportFirst international F-35 delivered to United Kingdom, confirmed
  3. Initial operating capabilityMarine Corps declares F-35B IOC, confirmed
  4. Combat useUS Marine Corps F-35B conducts first combat strikes, confirmed

Short takeoff and vertical landing (STOVL) variant of the F-35 Lightning II, with a rear exhaust nozzle that swivels downward and a shaft-driven lift fan so it can operate from amphibious ships and short or unprepared sites. Its primary U.S. operator is the Marine Corps, which plans to procure 353 F-35Bs to replace AV-8B Harriers and F/A-18 strike fighters.

Timeline4

  1. First flightConfirmed

    F-35B completes first flight

    First flight of the short-takeoff/vertical-landing F-35B variant; distinct from both the X-35B demonstrator and the earlier F-35A flight.

  2. ExportConfirmed

    First international F-35 delivered to United Kingdom

    The first international delivery was an F-35B for the United Kingdom; delivery does not indicate UK operational capability.

  3. Initial operating capabilityConfirmed

    Marine Corps declares F-35B IOC

    Variant-specific IOC; not a declaration for the entire F-35 family.

  4. Combat useConfirmed

    US Marine Corps F-35B conducts first combat strikes

    Marine Corps F-35Bs struck targets in Afghanistan during Operation Freedom’s Sentinel. This dates US F-35B combat use, not the first combat use by every F-35 operator.

The latest 10 milestones. Solid entries are confirmed, outlined reported, dashed estimated or still to come; dotted italic entries are speculative. Dates show only the precision the sources give.

Operators5

  • ITItaly
  • JPJapan
  • SGSingapore
  • GBUnited Kingdom
  • USUnited States
First fielded
2015
Combat use
Documented · US Marine Corps F-35B conducts first combat strikes (Sep 27, 2018)

Programs & Awards1 programs

Programs1

Cost to the Government

  • Unit cost (flyaway)Reported
    $121M
    Estimate / observation: 2026-09 · Then-year $

    F-35B average price for Lots 18-19 as confirmed by the F-35 JPO to Breaking Defense (reported Sept 2026); up from $109M in Lots 15-17.

    Source
Earlier cost observations (2)
  • F-35B Lightning II · Unit cost (flyaway) · $74.6M
    Estimate / observation: 2023-12 · BY2012 $ · 353 units

    Average unit recurring flyaway cost from the December 2023 (Modernized) SAR via CRS R48304 Table 2, constant CY2012 dollars, assuming 2,470 U.S. and 918 international sales; hardware includes airframe, vehicle systems, mission systems, engine and ECOs over the life of the program. quantity = planned U.S. buy of this variant in the program of record, not the number of aircraft the figure was priced on.

    Source
  • F-35B Lightning II · Unit cost (flyaway) · $109M
    Estimate / observation: 2023-10 · Then-year $

    F-35B average flyaway price for Lots 15-17 (delivered CY2023-2025) per F-35 JPO spokesman Russ Goemaere to Breaking Defense.

    Source

Unit costs and contract unit prices for this system, and budget figures for the programs that buy it. Each figure states its dollar basis and links its source; contract values are under Programs & awards.