F-35 Upgrade List To Transform Strike Fighter’s Future Role

This is the vision for the Lockheed Martin F-35 program in 10 years:

A worldwide fleet of more than 2,000 fighters is in service with a still-growing list of customers. Sales are spurred by a unit procurement price and cost per flight hour equal to or only slightly higher than a fourth-generation fighter. Yet the newly modernized Block 4 fleet of F-35s boasts 25 times more computing power than the version of the aircraft operating today, enabling the software-based onboard fusion engine to mine data from a far more advanced set of active and passive sensors.

As the situational awareness in cockpit expands, the pilots have a variety of new weapon options available: the ability to carry six Lockheed Martin AIM-260 or Raytheon AIM-120 advanced medium-range air-to-air missiles internally; a maritime strike capability of the Joint Strike Missile; and the use of new long-range strike missiles, such as the future Stand-in Attack Weapon (SiAW) internally and possibly a hypersonic cruise missile carried externally. Meanwhile, the Lot 22 F-35 rolling off Lockheed's assembly line in 2030 also can access a new class of air-launched attritable stores that add vast new sensing capacity, multiply weapon loadouts and, depending on the mission, serve as kinetic options themselves.
The F-35's role has already evolved from standard counterair and strike missions. The Army and Navy now use the F-35's sensor data remotely to guide their interceptors to knock down incoming missiles. The Air Force's decentralized command-and-control system relies on the F-35's processing power, sensor data and communication hooks to orchestrate a wider attack in all domains. F-35 pilots still train to perform traditional fighter missions, but the role the aircraft plays defies the vocabulary of the Air Force's designation system.
A decade may seem too short for such an evolution in one program, but it is possible. Ten years ago, the F-35 was still in crisis mode: With the flight-test fleet grounded for most of 2009, the supply chain was reeling. Ashton Carter, who was then the undersecretary of defense for acquisition, technology and logistics, later acknowledged that proposals to cancel the program had been briefly considered during that period.

To date, Lockheed has delivered more than 500 F-35s to nine countries, with another three countries signed up for still more. The unit flyaway cost of an F-35A will fall to $77.9 million for aircraft delivered in 2022 as part of the 14th lot of yearly production.

In plotting the program's next decade of development, a similar narrative of early struggles is becoming clear.

Schedule pressure grows on computer upgrade
First Block 4 upgrades arrive late and flawed
The F-35 Joint Program Office (JPO) identified the first 66 hardware and software upgrades listed under the Block 4 Follow-on Modernization in a report to Congress in May 2019. The first eight upgrades were due to enter service in 2019, but because of unexpected complications, only one of them—an automatic ground-collision avoidance system—was released to the operational fleet on time. Other improvements, such as an interim full-motion video capability for the Marine Corps' F-35B fleet, fell behind due to later hardware deliveries, according to a Government Accountability Office (GAO) report released in May.

The JPO also adopted an agile development process for Block 4. The upgrades are still organized in four major increments—Block 4.1, 4.2, 4.3 and 4.4—and smaller batches of new capabilities are released in six-month cycles, a process called Continuous Capability Development and Delivery (C2D2). Lockheed, for example, is scheduled to complete development of 30P5 software in the third quarter of this year, which will be followed by software drops called 30P6 in the first quarter of 2021 and 30P7 in the third quarter of 2021. The agile development method is intended to reduce the scale of delays caused by a release of a large batch of flawed software every two years, but it is not a panacea. As the software from the first C2D2 release entered testing, new problems appeared, such as Block 4 software code causing "issues" for Block 3F functions that had been working, according to the GAO.

The next major advance for the Block 4 program should arrive in 2023. This Block 4.2 configuration will be the first to include Technical Refresh 3 (TR-3) hardware, which includes a new integrated core processor, an aircraft memory system and a panoramic cockpit display system. As the first cockpit computing for the F-35 since Block 3i appeared in 2016, the TR3 will enable a leap in sensing capability, especially for the BAE Systems ASQ-239 electronic-warfare system.

In addition to upgrading the F-35's panoramic cockpit display, the ongoing Technical Refresh 3 upgrade will install a new integrated core processor that is 25 times more powerful than the current version. Credit: U.S. Air Force
The TR-3 upgrade, however, also is facing development challenges. The F-35 JPO is seeking a $42 million increase in spending on TR-3 in fiscal 2021 to offset higher "technical complexity."

"Suppliers are challenged to meet a demanding schedule with one holistic hardware-software system; therefore, interim releases of hardware [will] reduce risk and enable parallel software development," the Air Force said in a budget justification document for fiscal 2021.

The latest F-35 selected acquisition report (SAR), which was released by the Defense Department in early July, reports similar issues with TR-3, citing specifically higher costs due to additional support needed to help one supplier manage the complexity of a field-programmable gate array used in the new processor system. The development of the integrated core processor and the aircraft memory system also are suffering delays, according to the annual SAR.

As the TR-3-equipped Block 4.2 configuration arrives in the fleet, the F-35's power to sense targets and threats passively should rise enormously. The upgrade also paves the way for a critical update to BAE's electronic-warfare system, especially the jamming techniques generators embedded in Racks 2A and 2B of the ASQ-239. BAE also plans to upgrade the wing-leading-edge-mounted receivers in Bands 2, 3 and 4 as well as activate new Band 5 receivers from broad spectrum coverage from very low to extremely high radio frequencies. Aided by the more powerful processors introduced by TR-3, the F-35 may be able to develop jamming techniques as it encounters new signals not previously stored in the aircraft's mission data files. Such a capacity for so-called cognitive electronic warfare is becoming critical as adversaries shift to software-defined radios and frequency-hopping radar arrays.

If the current schedule is maintained, the TR-3 and Block 4.2 upgrades arriving in Lot 15 aircraft will include more than improved computing power. Lockheed is modifying the internal weapons bay to enable the "sidekick" upgrade, which increases the Raytheon AIM-120 missile loadout by 50% to six missiles. As the Lockheed AIM-260 becomes available, the same loadout will become possible with a missile measuring the same length as the AIM-120 but with significantly more range.

The same modification also accommodates the dimensions of the Air Force's new SiAW missile, which adds a new warhead to the Navy's Advanced Antiradiation Guided Missile-Extended Range. An Israeli-funded program to add wing-mounted fuel tanks to the F-35's loadout options also should become available and would increase the range by 25% if the mission does not require minimizing the aircraft's profile on radar.

By the end of the decade, operating the F-35 could be very different from how the aircraft's designers in the late 1990s had anticipated. The Air Force's Skyborg program seeks to introduce a new family of ground- and air-launched aircraft that can serve as autonomous teammates, or wingmen, for F-35 pilots. "Skyborg" itself refers to the development of a new autonomous control system that can be trained to perform a diverse set of missions. The Air Force expects F-35 pilots to use the Skyborg-equipped aircraft much like reusable munitions; in other words, a missile that can be fired and, if no worthy target appears, recovered and used again.

The capabilities envisioned by the F-35's designers two decades ago are now available in operational aircraft, albeit several years later than originally envisioned and for higher procurement and operating costs. As the next decade unfolds, the JPO and Lockheed will seek to add capabilities that have become defined only within the last decade and to adopt several concepts, including Skyborg and SiAW, that have emerged only recently. The history of the F-35 program is characterized by overpromising and underperforming in the development phase. As Block 4 development transitions from concept to reality, the challenge will be avoiding similar missteps.


Optimistic

After short-term stagnation, global defense spending resumes growth and Lockheed delivers 4,000 F-35s overall 
Despite early concerns, Lockheed completes the Block 4 modernization program on-time and on-budget


Neutral

Global defense spending stagnates through 2040, increasing downward pressure on programs of record
Block 4 modernization suffers some delays and overruns but does not affect aircraft procurement


Pessimistic

Global defense spending enters a long-term decline, setting off a 1990s-style "procurement holiday" for fighters
TR-3 Refresh and Block 4 are delayed significantly, with cost overruns leading to further cuts in the procurement budget