Key point: The Air Force is working toward having the F-35 fire a wide range of emerging weapons.
The Air Force is already working on an emerging 4th F-35 "software drop" designed to enable the stealth multi-role fighter to fire an even wider range of emerging weapons such as the new, high-tech Small Diameter Bomb II.
Following the drop of the now-operational 3F, the aircraft will incorporate new software drops in two-year increments in order to stay ahead of new threats - and service developers say a 4th software drop will be ready by 2020 or 2021.
Block 4 will include some unique partner weapons including British weapons, Turkish weapons and some of the other European country’s weapons that they want to get on their own plane, service officials explained.
A big part of the developmental calculus for Block 4 is to work on the kinds of enemy air defense systems and weaponry the aircraft may face from the 2020’s through the 2040’s and beyond.
In terms of weapons, Block 4 will eventually enable the F-35 to fire cutting edge weapons systems such as the Small Diameter Bomb II – an air-dropped bomb able to destroy targets on-the-move.
While the Air Force currently uses a laser-guided bomb called the GBU-54 able to destroy moving targets, the new SDB II will be able to do this at longer ranges and in all kinds of weather conditions. In addition, the SDB II is built with a two-way, dual-band data link which enables it to change targets or adjust to different target locations while in flight.
The Small Diameter Bomb II uses a technology called a tri-mode seeker, drawing from infrared, millimeter wave and laser-guidance. The combination of these sensors allows the weapon to track and eliminate moving targets in all kinds of weather conditions from long distances.
A tri-mode seeker provides a range of guidance and targeting options typically not used together in one system. Millimeter wave radar gives the weapon an ability to navigate through adverse weather, conditions in which other guidance systems might encounter problems reaching or pinpointing targets.
Imaging infrared guidance allows the weapon to track and hone in on heat signatures such as the temperature of an enemy vehicle. With semi-active laser technology, the weapon can be guided to an exact point using a laser designator or laser illuminator coming from the air or the ground.