What are the Pros and Cons of the F-35 Fighter Jet? Issues the F-35 Program Needs to Address: Part-5

The F-35 program has faced a number of challenges over the years. These include the need to redevelop the aircraft's software, engine modification, logistics information system, etc. In this article, I will try to clarify these issues.

Software Development and New Versions (Blocks): Block-4 Release

No matter how you look at it, the F-35 is a fifth-generation aircraft with sharp and angular 'facial' features. The F-35 is also a flying computer. Thanks to an enormous software that is invisible from the outside, the F-35 fighter jet is able to fulfill the missions expected of it. In a nutshell, the F-35 is known as a 'stealth fighter designed to perform missions while avoiding enemy radars'. 

With its new technologies, the F-35 is an aircraft that offers new capabilities and new opportunities to its users. With its ability to penetrate enemy depths almost undetected with low visibility, it is a fighter jet that significantly outperforms its competitors. Its avionic systems, together with network-centric operations, are seen as a force multiplier that provides superiority to any air force that adds this aircraft to its inventory.

The software codes of the aircraft and support systems, which are at the center of all these capabilities, totaling 24 million lines in total, make the F-35 fighter aircraft a flying mission computer. 

The F-35's most distinguishing feature is its sensor and weapon integration, both internally and with other aircraft. Since this integration is accomplished primarily through complex software, the writing, verification and debugging of this software is a continuous process for the F-35. The F-35 operating software is built in blocks, and is deployed in block versions or releases. Each time a new block/version is introduced, new software capabilities are added to the aircraft in the new block. Thus, similar to the differences between the version of Windows 7 that we install on our computers at home and the higher version, say Windows 10, there can be big differences between the F-35 Block software. Just as we need Windows 10 to run some programs, the F-35 needs the new Block version to perform some tasks and use some weapons. If the new software version is not installed on the aircraft, some sensors, avionics, weapons, etc. will not work. 

I would like to draw your attention to the fact that this software is being updated centrally in an integrated structure led by Lockheed Martin with the support of the relevant companies under the control of the F-35 program office. As I have written before, not only is there an American policy against sharing the source codes used in the aircraft, but even if the source codes are given to the user countries, not all countries may have the technological capability to make these updates. In this case, dependence on the US side will continue in the technological dimension. In order to get rid of this dependency, it would be necessary to switch to a new structure similar to the Pardus operating system instead of Windows, for example, which would mean that countries would have to undertake a huge workload equivalent to reproducing the airplane in terms of software, in line with their own national expectations. How many countries can undertake such a cost-increasing workload? In a sense, it would be necessary to undertake a development project that would cost more than its original value.

The fact that the first F-35As had slightly better mission software than conventional aircraft was initially deemed sufficient. Early F-35As did not have the sensor fusion or weapons integration capabilities that later F-35s had. F-35As were produced with a software version (Block 1B) that was complex at the time, but actually quite simple when we look at the new blocks or software versions. A similar block approach applies to all modern fighter aircraft. For example, there is a huge difference between the F-16 Block-10 and the latest Block-70. This kind of 'Block' approach, which we can call phased production or phased development, not only allows the aircraft to be delivered to the user without delay, but also enables more advanced aircraft versions to be acquired over time by addressing the requirements that emerge as the aircraft is used and other requirements that are being worked on. In other words, instead of a static aircraft, a dynamic aircraft production mechanism with a dynamic development process is put into effect. This is also the case for the F-35 aircraft.

In this context, the Block-4 software version is planned to be commissioned in the near future. With the currently planned final software version Block-4, it is aimed that the users of the aircraft will have a brand new war machine in terms of operation. With the Block-4 version, which is expected to enable the use of avionic systems at the highest level, the aircraft's mission systems will be further improved (upgraded). 

New Radar

With the Block-4 release, the AN/APG-85, Northrop Grumman's advanced, multifunctional AESA fire control radar, will be deployed on all F-35s. The new radar is expected to provide pilots with greater situational awareness, improve survivability by enabling better use of self-protection systems, and provide a spectrum of emerging threats. According to some sources, the new radar could be ready for flight tests by 2025. Until APG-85 is commissioned, the electronic warfare capabilities and software of APG-81 will continue to be improved.

New DAS

The weight-reduced AN/AAQ-37 new generation DAS will also be put into use. Thus, the performance of this integrated sensor system is expected to be doubled and it is expected to provide a more reliable service.

Enhanced EOTS

With the Block-4 software, a more advanced EOTS sensor will be used on the F-35. Capabilities such as higher performance, increased target detection and recognition ranges, and improved image detector resolution will be provided to the aircraft. In addition, a more advanced version of AN/ASQ-239 (Electronic Warfare) will be introduced.

With Block-4, the aircraft of countries that want to use nuclear weapons will also gain the ability to fire nuclear weapons. In order for the Block-4 version to be installed on the aircraft, the aircraft must be produced/upgraded with technical renewal (TR-3) equipment. Aircraft from the 15th production line (Lot) will start to be delivered this year with TR-3 features. 

In addition, there will be upgrades such as weapon mounts, cooling systems, mission computer processors, etc.

As with any modernization activity, there is a cost to install the Block-4 version on the aircraft. Considering the next 6 years, the total cost of the Block-4 development/installation process is estimated to reach 10.8 billion dollars. This cost, which will be allocated to all aircraft, will ultimately bring an additional burden of approximately 3 million dollars per aircraft when considered as a unit cost. The fact that users will have to bear these costs at each block, unlike other conventional aircraft, creates a serious cost for users in the life cycle of the aircraft, even in terms of software versions alone.

F-35A (Air Force Version) Engine Upgrade

The Pentagon wants to replace the F135 engine used in the F-35A variant with a new engine model. The new engine is intended to incorporate advanced composites and new engine technologies. Thus, it is expected to increase efficiency in fuel utilization and make improvements in the areas of tactical-speed-range-heat management. The engine is also expected to perform better in special configurations and conditions. The Air Force argues that by adding an adaptable engine to the F-35A, more power and better heat management should be achieved, and an engine that is compatible with upgrades in the coming years should be used as needed. On the other hand, the fact that the development and production costs to meet the requirements of the new engine could reach $6 billion, and that the new engine option could result in a shortage of resources, has led to the possibility of shelving this option in the event of budget constraints.

In August 2022, Pratt & Whitney, GE and three other engine companies signed a 'prototype engine development' contract to develop an engine that meets the requirements of the Air Force. Once the best prototype engine had been identified, mass production of the new engines could begin. The development process is expected to take several years and the new engine is expected to be operational before 2030.

Targets Expected to be Achieved in the F-35 Global Sustainability (Sustainment) System

The F-35, like the F-16 before it, is about to become an airplane with a global reach. The three US services (Air Force, Navy and Marine Corps) and user nations are procuring the aircraft with the expectation of receiving immediate logistical support wherever the aircraft operates in the world. For this to happen, the governments and industries of user countries in the United States and around the world need to act in concert. In this context, the Autonomic Logistics Information System (ALIS), which operates in connection with pilot, technician and aircraft maintenance personnel training, daily fleet flight and maintenance activities, regional logistics warehouses, major maintenance, modernization facilities, 24/7 global maintenance and tracking services, and related supply chain management, works in an integrated structure. The F-35 maintenance and sustainment system is intended to provide high-reliability, predictive health monitoring, expedited supply chain and condition-based maintenance services. The global maintenance and overhaul system aims to achieve an aircraft activity rate of 80 percent or higher by 2025, with a flight hour cost of no more than $25,000. In a way, it is aimed to provide fifth-generation capability to users at a cost similar to the cost of fourth-generation aircraft operation/operation.

Autonomous Logistics Information System (ALIS)

The backbone of the F-35's global maintenance and sustainment system is ALIS, the logistics information system, which is often viewed by users as a complex system. ALIS is at the center of maintenance and supply chain management for F-35 operations. This center, which monitors all kinds of logistics information of the aircraft and works in integration with supply support, also functions as a data bank where aircraft maintenance personnel constantly input and output data, and where all logistics data of the aircraft can be seen in real time. 

ALIS is not yet a fully developed system. Nevertheless, without ALIS, the F-35 cannot operate anywhere in the world. In a way, without ALIS, which is equivalent to the Logistics section of the Turkish Air Force's Air Force Information System (AFIS), it is not possible to carry out aircraft operations and related maintenance activities. In this logistics information system, where everything has moved into the digital world, it should not be expected otherwise. Manual use has become almost impossible. 

It is believed that some of the problems that arise with the use of ALIS can only be solved through system improvements. As the number of F-35 users increases, the speed of these improvements causes the F-35 program management to struggle with the ALIS aspect and to support operations that may be carried out anywhere in the world. In a multinational program, I see ALIS issues as a truly intractable logistical problem area. The challenges, difficulties and shortcomings in ALIS can cause countless delays in troubleshooting aircraft malfunctions and restoring malfunctioning aircraft to mission readiness.

Furthermore, the lack of a backup of this digital maintenance information system is also a point of criticism. The current design of ALIS is based on routing F-35 data to a Central Entry Point and then to the main operating unit of ALIS. Since this setup is designed to operate without a back-up system, the system operates on a cycle of "on" and "off". In other words, in the event of a failure in this loop, the entire F-35 fleet can be taken offline. In such cases, manual methods are used to overcome the shortcomings of ALIS. 

Aware of the shortcomings of the system, the F-35 program office has implemented the principle of flexible use. Accordingly, F-35s were allowed to fly without the automated ALIS (version 3.5) for at least 30 days. Aircraft mission, firing, flight control, avionics, etc. systems are capable of operating without ALIS from engine start-up. In this method, there is no problem in terms of flying the aircraft. 

Is there a need for ODIN architecture instead of ALIS architecture? 

It is widely believed that some of the problems with ALIS stem from the legacy architecture dating back to the 1990s. With this in mind, the F-35 program office decided that instead of further upgrading ALIS versions to take advantage of modern programming architectures, they should radically change the system and move forward with a new architecture. Replacing ALIS with the Operational Data Integrated Network (ODIN) and using a system compatible with new technologies seemed a more logical path. 

However, the ODIN idea was shelved due to the lengthy development process and the additional costs it would impose on the program. 

Now, instead of replacing ALIS, the F-35 program office is trying to implement a phased plan to make improvements and modernize the system as much as possible. Since the legacy architecture remains untouched, the planned ALIS improvements will include small-scale hardware changes and the introduction of a new program that will provide more comprehensive access to ALIS. It has not yet been announced when the transition to the new ALIS will take place. According to experts, it is likely that the improvements will be completed within the next 3 years, after which the new ALIS will be deployed.

No Flight without ALIS?

In the logistics information system leg of the aircraft, the software running on the ground computers within the scope of ALIS includes the aircraft's supply chain, aircraft configuration management, fault diagnosis, new mission planning and information/reporting systems. Since none of these systems are critical for flights, F-35 flight operations can be conducted without ALIS for a certain period of time. The ALIS system must be updated at least every 120 days.

ALIS was created to autonomously manage the global maintenance and sustainment system designed to ensure the combat readiness of the F-35 fighter jets and the supply system within it through a global internet network. Since everything is managed through this network subject to centralized control, and since the US is naturally at the center of this work, it inevitably makes all user countries of the F-35 aircraft dependent on the US. In reality, ALIS, which attracts a lot of attention in this respect, can even be characterized as a relatively innocent element compared to other dependencies (software codes, avionics, weapon integrations, etc.).

ALIS Forces Transparency in the Maintenance, Sustainment and Supply System of User Countries

Modern logistics systems are designed to report aircraft malfunctions to the center/centers on the ground via a closed internet network to which the aircraft in the air is also connected, to have the necessary parts ready at that square before the aircraft lands at the planned square, if possible, and to fix the malfunction as soon as possible. In this way, it is aimed to both prevent the aircraft from being out of operation and to save the system from the drawbacks of distributed logistics architecture, storage costs, unnecessarily keeping too many parts, systems, components in warehouses, incurring the cost of not being able to use them due to the end of shelf life in some cases, etc. by keeping logistics warehouses in centralized locations. ALIS also serves this purpose. The situation that perhaps disturbs the user countries here is that all information about the aircraft, such as the activity rates, the weapons used, the training status of the pilots, in which configurations flight training is carried out, etc., is transferred 24/7 to the USA, the main manufacturer of the aircraft, via ALIS. 

It is not possible to integrate a system or use different parts into F-35s or even F-16s without the knowledge of the manufacturer. The software does not allow such an application, and the US can be instantly informed about the 'foreign part' through ALIS. We do not even want to have a sub-industry part installed in our own automobiles. For a country with the same understanding, there is no harm in using original parts in its F-35s. If there is a prior agreement with Lockheed Martin, some parts, for example, can be produced in Turkey and integrated into the aircraft. Any other practice is already unethical. 

After all, in such modern aircraft, if you have to develop indigenous solutions for your own national needs, you have to work together with the manufacturer of the aircraft. Again, when we look at the modernization process of the F-16 aircraft, as I mentioned at the beginning of my article, a 'secret' modernization without the knowledge of the US would be possible by developing Pardus-like software instead of Windows. Such a step would mean disconnecting your entire system from the system of the producer country, which would lead to the questioning of your relations with that country both in terms of international relations and in all other areas such as commercial, technological, scientific, etc., especially in the defense industry. Therefore, modernization activities must be carried out within the rules of the modern world. With ALIS, the US has made such irregular modernization methods almost impossible and brought them under its control.

In the sixth part of this series, I will talk about the multinational structure of the F-35 program and the effects of Turkey's exclusion from the program.