Lockheed Martin's F-35 Lightning II stealth fighter jet is often cited as the most expensive weapons project in human history, with a total projected program cost exceeding $1.7 trillion. Despite its unparalleled technological advances, the program has been plagued by a series of cost controversies, particularly regarding long-term operational and maintenance costs. At the heart of these spiraling financial problems lies its Pratt & Whitney F135 engine, a perfect example of the adage (save early, spend later).
- The F-35 was designed as a multi-purpose platform requiring extraordinary power for its three variants (CTOL, STOVL, and CV), all powered by a single engine: the F135. This engine is essentially a twin-shaft, axial-flow afterburning turbofan with the highest thrust ever built for a fighter aircraft. However, despite its phenomenal thrust, the F135 was developed during an era where innovation in aircraft engine technology was stalled due to budgetary decisions that prioritized low acquisition costs over long-term efficiency.
Crucial decisions that shaped the F-35's cost destiny were made decades ago. While the aircraft was still in design, the Pentagon and its engine manufacturers had the opportunity to develop a far more advanced engine, an adaptive cycle engine. This type of engine (as proposed in the Adaptive Engine Transition Program (AETP) could optimize engine airflow for increased thrust in combat and higher fuel efficiency during cruise flight. However, due to concerns about reducing development costs during the early stages of the Joint Strike Fighter program, this idea was rejected.
A clear example of “early bird savings” is the cancellation of the alternative engine, the General Electric/Rolls-Royce F136. Having two engine suppliers typically encourages innovation, lowers costs, and ensures supply. However, due to budget pressures in 2011, the F136 program was canceled. This decision effectively gave Pratt & Whitney a monopoly on the F135 engine, eliminating competitive incentives and locking the US Department of Defense into a single solution, regardless of any subsequent issues.
- As the F-35 evolves, particularly with hardware and sensor upgrades known as Technology Refresh 3 (TR-3) and Block 4, the aircraft's electrical power and cooling requirements have skyrocketed. The F-35's stealth electronics and advanced weapons systems generate enormous amounts of heat. The F-35's engines, designed without adequate power margins and cooling, are now forced to work much harder.
This excessive workload causes the F-135 engines to operate at higher temperatures than expected, accelerating wear on internal components, particularly the turbine blades. This overheating issue leads to premature failure (cracking) of engine components. This has forced the US Air Force and other F-35 operators to recall aircraft early for unscheduled maintenance, significantly reducing fleet readiness.
The immediate impact of these reliability issues is a surge in operational maintenance costs. Engine parts must be replaced more frequently, repair times for each engine increase, and the entire supply chain becomes strained. The F-35's cost per flight hour, originally promised to be comparable to fourth-generation fighters, has far exceeded it, creating a massive financial burden on the defense budget in the long term.
- To address these issues, the Pentagon is now being forced to invest billions of dollars in an urgent upgrade program called the Engine Core Upgrade (ECU) for the F135 engine. This ECU aims to restore lost power and cooling margins. Ironically, the billions of dollars spent on this “wasteful late fix” could have been avoided had the Pentagon pursued the Adaptive Engine Development Program (AETP) several years ago, which would not only have addressed these issues but also delivered significant performance improvements.
Failure to invest in a more powerful and efficient engine early on is now not only a financial burden but also a threat to combat readiness. Previous estimates indicate that a significant portion of the F-35 fleet may be grounded by the mid-2020s due to engine issues that cannot be repaired in a timely manner. This undermines the F-35’s promise as the backbone of global air dominance for the US and its allies.
The story of the F-35's F135 engine serves as a costly case study in military procurement. Decisions to save a penny (millions of dollars) in early development have resulted in losses of a pound (billions of dollars) in long-term operational and maintenance costs. It's a painful reminder that in military technology, delaying critical innovations for short-term savings almost always results in significantly higher bills and a less capable fighter aircraft in the future.
- GlobalNews...