Finland Enhances F-35 Strike Power With New US Weapons

The Finnish Ministry of Defence announced on Thursday that it has authorized the procurement of GBU-53/B Small Diameter Bomb II (SDB II) precision-guided glide bombs from the United States. The acquisition will add an air-to-ground capability to the Finnish Air Force’s future fleet of 64 Lockheed Martin F-35A Lightning II fighter jets, supplementing a prior weapons contract finalized in 2023.

The munitions, also known as StormBreaker, will be manufactured by Raytheon, a subsidiary of US defence contractor RTX. The transaction will proceed under a Letter of Offer and Acceptance (LOA) within the US Foreign Military Sales (FMS) program. In addition to the munitions themselves, the procurement package includes technical manuals, documentation, spare parts, accessories, transportation services, and ongoing training, maintenance, repair, and contractor support.

The deal builds on a 2020 authorization by the US Congress, which approved the potential export of up to 500 SDB II weapons to Finland as part of the F-35 package offered during the HX fighter procurement program. Finland later signed an initial FMS agreement for the Raytheon-developed munitions in 2023, valued at approximately €35 million (US$40.1 million).

“This procurement complements a previous order as part of the overall F-35 acquisition,” Finnish Minister of Defence Antti Häkkänen said. “It represents a new type of capability that strengthens Finland’s defence capability even under demanding conditions. The glide bomb is a technically advanced system that supports the effective use of F-35 materiel as part of the defence system.”

The GBU-53 StormBreaker weighs approximately 113 kg and carries a shaped-charge blast-fragmentation warhead designed to neutralize both soft and hardened tactical targets. Its core architecture features a tri-mode seeker that integrates millimetre-wave radar for tracking objects through obscured environments, imaging infrared for target recognition, and semi-active laser guidance.

Operating alongside GPS and inertial navigation systems, an internal mission computer allows the weapon to autonomously locate and classify targets. An integrated two-way datalink enables in-flight retargeting and tracking updates, supporting engagement of moving targets in rain, smoke, dust, and darkness. Its compact design allows a single F-35 aircraft to carry multiple munitions simultaneously.

Finland originally committed to its broader fighter modernization programme in 2021, purchasing 64 F-35A aircraft in an €8.4 billion (US$9.63 billion) agreement. The first deliveries are scheduled to begin in 2026, with full operational capability expected by 2030.

“The precision-guided glide bombs now being procured will supplement our previous order as part of the F-35 weapon package,” said Colonel (ret.) Henrik Elo, Director of the F-35 Programme. “The SDB IIs are technologically advanced and will bring the F-35 armament capabilities the Finnish Air Force did not previously have. The ability of the glide bomb to strike moving targets in challenging weather conditions will enable effective use of the F-35 in Multi-Domain Operations across all defence branches.”