The F-35 fighter is the technically most advanced fighter jet currently in serial production.
It is capable of performing a diverse array of missions, from air-to-air combat to precision
bombing to radar jamming to intelligence gathering.
With 16 countries having committed to purchasing it, the advanced jet is receiving widespread
acceptance across various nations.
While the original configuration is very well thought out, it will need significant upgrades
to maintain its edge as the fighter will be operating till 2070.
In line with this, the Joint Program Office has begun executing the most ambitious round
of upgrades since the fighter’s inception two decades ago, called Block 4.
Block 4 will introduce over 75 major upgrades to the fighter.
In this video, Defense Updates analyzes how F-35 is getting much more lethal ?
Let’s get started.
To enable the fighter for the Block 4 upgrade it will get a Technology Refresh-3 enhancement.
One could view the TR-3 initiative as a form of brain transplant that will grant the fighter
an immense boost in computational capabilities and memory storage.
Additionally, the new system architecture is tailored not only to enhance the functionality
of nearly every system on board but also to simplify the integration of future upgrades.
As part of the TR-3 program, a new computing core has been incorporated, which boasts a
remarkable 25-fold increase in processing power compared to the current F-35.
As per Defense contractor L3 Harris, this power boost will be combined with other enhancements
to deliver an even more astonishing "37-fold increase in computing power" in due course.
The upgraded processor is expected to have a significant impact on a wide range of onboard
systems, such as radar processing, electronic warfare suite, guidance, communications, and
the distributed aperture system.
In support of all this new power is a similarly impressive 20-fold increase in data storage.
While the Technology Refresh-3 effort could be seen as laying the foundation for massive
upgrades to come, the truth is, this effort alone will result in a dramatic uptick in
the fighter’s capability set.
A significant part of the Block 4 upgrade will come in the form of newly integrated
weapons, which according to some reports, include the Joint Strike Missile, the AGM-88G
Advanced Anti-Radiation Guided Missile Extended Range (AARGM-ER) for taking down enemy air
defenses at standoff ranges, and European Meteor air-to-air missile which is widely
considered to be best Beyond Visual Range Air to Air weapon.
Importantly, the weapons payload will also increase.
Block 4 reportedly includes an expansion of the F-35’s internal weapons carriage capacity.
Today’s F-35s fly with a maximum of just four weapons stored internally while maintaining
a stealth profile, but Block 4 will increase that to six, allowing the fighter to carry
more ordnance into the fight than ever before.
Lockheed Martin has designed a new weapons rack named ‘Sidekick’ to enable the F-35A
and C to carry two more missiles internally.
Sidekick adds a little extra weight but enables each of the two weapons bays to carry three
AIM-120s instead of the current two, for a total of six internally carried AMRAAMs.
This puts it at par with F-22 Raptor in this aspect, and greatly enhances its overall lethality
in the air-to-air combat arena.
Currently, F-35s fly with the Northrop Grumman-sourced AN/APG-81 Active Electronically Scanned Array
Radar onboard, widely touted as the most powerful and capable radar system ever to fly in a
tactical fighter.
The system is highly potent, enabling it to not only detect and trail targets in the air
and on the surface but also to function as an electronic warfare tool, disrupting adversary
radar systems while airborne.
Nonetheless, despite its excellent capabilities, it is set to be superseded by an even more
robust radar array called the AN/APG-85.
Northrop Grumman has said only that this new radar system “will incorporate some of the
latest technologies available and help ensure air superiority.”
This has led many to speculate that this new radar will use GaN (Gallium Nitride)-based
TRMs (Transmit/Receive Modules).
The newly introduced TRMs provide a substantial boost in power transmission and clarity, even
in the face of electronic countermeasures.
Additionally, they offer superior thermal management, enabling more power to be channeled
through them for both target acquisition and electronic warfare operations.
As Aviation Week’s Steve Trimble reported, this new design has the potential to double
the F-35’s target detection range with the same power output and the same size array,
giving the F-35 a distinctive edge against other fighters in beyond-visual-range engagements.
The AN/AAQ-37 Electro-optical Distributed Aperture System (DAS) in F-35 enables unprecedented
situational awareness.
DAS consists of six high-resolution infrared sensors mounted around the F-35's airframe
in such a way as to provide unobstructed spherical (4π steradian) coverage and functions around
the aircraft without any pilot input or aiming required.
The DAS provides three basic categories of functions in every direction simultaneously:
1.
Missile detection and tracking (including launch point detection and countermeasure
cueing).
It can detect and track ballistic missiles to ranges exceeding 800 miles (1,300 km) and
has also demonstrated the ability to detect and track multiple small suborbital rockets
simultaneously in flight.
2.
Aircraft detection and tracking (situational awareness IRST and air-to-air weapons cueing)
3.
Imagery for cockpit displays and pilot night vision.
Pentagon says that the upgrade to the DAS will increase performance and reliability
with a “larger pixel focal plane array” and higher operating temperatures.
F-35’s increasingly complicated on-board computers need more electric and cooling capabilities
In order to power all of these new systems, the F-35 will need an engine upgrade which
led to a battle between engine providers - General Electric and the F-35’s current engine producer,
Pratt & Whitney.
Pratt & Whitney proposed what the company calls an evolutionary Engine Core Upgrade
(ECU) that would increase the jet’s existing F135 engine’s thrust by 10% while improving
fuel efficiency by 5%, resulting in what they claim is a 7% increase in range.
GE, on the other hand, proposed integrating their XA100 adaptive cycle engines that offer
a 25% increase in fuel efficiency, a 20% increase in thrust, twice the heat management, and
as much as 35% more range.
US Air Force Secretary Frank Kendall informed the media that the service finally made its
call by closing its Adaptive Engine Transition Program
While this marks a setback for General Electric and curtails any chances for a revolutionary
upgrade, the engine Core Upgrade (ECU) by Pratt & Whitney is still a significant boost
especially since it comes in at half the development cost.