F-35 modernization to increase internal missile capacity by 50 percent

The Pentagon has unveiled plans for a major modernization of the F-35 Lightning II fighter jet, part of the broader Block 4 upgrade. A central component of this initiative is the ‘Six in the Bay’ program, which aims to increase the aircraft’s internal missile capacity by 50 percent, moving from four to six missiles. This enhancement allows the jet to carry more ordnance without using external weapon stations, thereby preserving its stealth characteristics and radar-evading capabilities during high-threat missions.

In addition to increased firepower, the F-35 is expected to receive a new Beyond Line of Sight (BLOS) communication system. This system will utilize Starshield satellites to transmit target data over long distances to command centers and other military units.

While the technical roadmap targets completion by September 2030, the specific F-35 variants to be upgraded and the exact types of missiles to be used remain unconfirmed. Discussions also persist regarding the strategic implications for NATO allies, including whether Polish F-35 fleets will receive these upgrades and the potential for these aircraft to participate in nuclear sharing missions involving B61 bombs.