On October 30th, the South China Morning Post published an interesting report, suggesting that China may potentially outmatch the United States in a new round of unmanned drone arms race. Earlier, the United States had announced a significant expansion of its drone production, but the latest news reveals that Chinese engine experts have developed engines at only 20% of the international average cost. With China’s impressive cost control abilities, this puts both China and the US in competition for unmanned drone equipment, and the outcome is easily predictable.
Engines at 20% of the cost: What’s the Structure?
According to the South China Morning Post, Zhu Junqiang, from the Institute of Engineering Thermophysics at the Chinese Academy of Sciences, mentioned that a new generation of high-speed, long-endurance drones equipped with low-cost jet engines is already in service. He stated that one of their significant focuses is to use low-cost advanced technology to incentivize the United States and other hostile nations to join the arms race. China’s exceptional cost control ability is set to give them an edge in this competition.
How high are the engine costs? For instance, the US military’s Global Hawk RQ-4 drone is equipped with the AE3007 engine, which costs nearly $4 million each. This engine is one of Rolls-Royce’s most advanced drone engines, known for its excellent performance and low fuel consumption, guaranteeing long endurance. However, its cost is significantly high, and when you factor in regular servicing and maintenance costs, the overall cost becomes even higher.
Zhu Junqiang stated that due to recent technological breakthroughs in China, the People’s Liberation Army (PLA) can acquire similar engines at less than 20% of the international average price. If these drones are mass-produced, it will result in a significant budget disparity or allow the same budget to equip more drones.
The South China Morning Post reports that China was a latecomer in the field of engines, as evidenced by the fact that the J-20 was only recently equipped with the high-performance WS-15 turbofan engine, and the C919 still uses CFM’s LEAP engine. However, in the field of drones, China’s latest engine technology applications have been much more flexible, allowing rapid integration into unmanned drone technology, a significant factor in recent engine breakthroughs.
Engines at 20% of the cost: What Technology is Used?
From the South China Morning Post’s description, the engines equipped in these drones are designed for high-altitude, high-speed, and long-endurance missions, which typically have contrasting performance requirements. Long-endurance is typically at odds with high-speed, but with the engines developed by the PLA, these two attributes have been seamlessly integrated. This is achieved by a compact single-axis turbofan engine.
Zhu Junqiang mentioned that this type of engine differs from the prevalent multi-axis, multi-stage fan structures. These engines connect various fans on a common axis at different speeds to achieve optimal coordination. While this structure offers the advantage of having each fan work at its optimal state, it comes at a higher cost.
For instance, the Global Hawk’s AE3007 turbofan engine uses two axes connected by a precision gearbox to achieve different speeds. This allows the large front fan to work at lower speeds while the high-pressure stage fan at the rear operates at higher speeds, achieving optimal performance.
In contrast, the Chinese single-axis turbofan engine has only one axis from start to finish, without gearboxes or gear meshing. Its design is simple and reliable, but it previously had some drawbacks. For example, the various fan stages compromised performance, thrust-to-weight ratio, and fuel efficiency. However, recent advancements in fan blade design and turbine inlet temperature have addressed these shortcomings. This engine’s performance now closely resembles high-performance aero engines and can easily meet the requirements of high-altitude, high-speed, and long-endurance missions.
To fully understand these two engine structures, it’s essential to have a basic understanding of jet engine design. However, for the purpose of this article, we’ll focus on axial-flow engines, and centrifugal or mixed-flow engines are not part of the discussion.
A jet engine is essentially a large cylinder with an axial shaft through its center. It contains fans of various sizes along this shaft. The front section of the engine has a larger diameter, while the fans in the front of the combustion chamber have smaller diameters. This design is optimized to compress air through the fans, with increasing pressure as it approaches the combustion chamber. Then, the air undergoes combustion with atomized fuel before being expelled from the rear.
Before expulsion, it passes through one or more high-temperature turbines, where it’s converted into mechanical energy to drive the various fans at the front. Consequently, a jet engine is a continuous self-sustaining system that continually propels the aircraft forward.
Single-stage or multi-stage turbines: The high-pressure turbine is a critical component that converts thermal energy into mechanical energy. It can be classified as single-stage or multi-stage. A single-stage turbine involves a single power shaft that drives the front fans at a consistent speed or varies speed through a gearbox.
A multi-stage turbine, on the other hand, involves high-speed turbines driving high-pressure stage fans at low speeds and low-pressure stage fans at high speeds. It typically requires a gearbox for synchronization. In the case of fighter jet engines, the gearbox’s effect on small bypass ratio fan engines is not very significant. However, in large commercial jet engines, it becomes much more noticeable.
Fan engines work by allowing a portion of the airflow passing through the engine’s front fans to bypass the engine and flow to the engine’s rear without passing through the combustion process. This bypass flow provides additional thrust without using extra engine capacity and is one of the main reasons why turbofan engines are more fuel-efficient than turbojet engines.
The Chinese single-axis turbofan engine has left many wondering how it achieves high performance with a small bypass ratio fan engine. To clarify, bypass ratio is the ratio of bypass airflow to core airflow. Large bypass ratios are more fuel-efficient and suitable for low-speed flight, while small bypass ratios are better for high-speed flight. For example, the WS-15 engine has a bypass ratio of less than 0.3, while the TRENT 900 engine in the diagram has a bypass ratio greater than 8.7.
This high-altitude, high-speed, long-endurance drone is capable of operating in a small bypass ratio condition while remaining fuel-efficient, as reported by the South China Morning Post. The engine’s simple structure and ease of maintenance reduce maintenance costs by 70%, and its fuel consumption is approximately one-third less than that of two-shaft engines. When considered from an overall perspective, the total cost of purchasing and operating drone engines has been reduced by about 80%.
Zhu Junqiang also noted that the engine features a redesigned afterburner and combustion chamber, allowing it to maintain stable performance at an altitude of 20,000 meters. Previously, low-cost aero engines often had unstable performance at this altitude, leading to high failure rates. This engine combines low cost and high performance, providing significant advantages for China in the future of unmanned drone technology.
US-China Drone Equipment Battle: Is the US Already Losing?
On February 18, 2023, the Eurasia Times reported that the United States is seeking to acquire a self-contained autonomous drone swarm system for anti-access/area-denial (A2/AD) operations. This system can command other drone swarms and effectively transform into thousands of drones, surface vessels, underwater drones, and ground drones to overwhelm the enemy’s military facilities.
The core of this system is the use of AI’s autonomous command capabilities to establish a cluster system of drones, autonomous surface vessels, and autonomous submarines in the air, on the sea, and underwater. This system would play a crucial role in countering China, as it would enable the United States to manufacture thousands of drones for strikes on China’s ballistic missile systems within its borders.
On September 3, 2023, the South China Morning Post reported on the “Replicator” program previously announced by the US Deputy Secretary of Defense, Kathleen Hicks. This program aims to build thousands of autonomous unmanned ships, aircraft, and other autonomous systems to counter China’s growing anti-access capabilities. Deputy Secretary Kathleen Hicks emphasized the need for the United States to achieve victory in this contest of attrition. She noted that the “Replicator” program is essential for victory because only with a substantial number of autonomous combat systems can the US maintain its combat capabilities even while sustaining losses.
This “Replicator” program is essentially a replica of the autonomous drone swarm system for anti-access/area-denial (A2/AD) operations mentioned earlier this year. Industry experts have made similar observations, and analysts point out that this is precisely what China has been doing over the past decade. Jon Grevatt, the Asia-Pacific news director at the US Defense Intelligence Agency, stated that China has swiftly and easily built a large number of unmanned systems by leveraging the integration of its military-industrial complex.
At this point, it has come to light that China’s drone engine costs are only 20% of those in the United States. If we consider this proportion, China’s military budget, which is only a fraction of that of the US, may allow China to equip itself with equivalent or even more military equipment than the US. This development could be a significant surprise to the US military. Competing with China in terms of drone numbers would essentially be similar to the fable of the Dragon King versus the Jade Emperor, as China’s experience in streamlining technology breakthroughs may be one of the most extensive in the world.
This is evident from China’s successful sales of drones. For example, India spent over $3 billion to purchase more than 30 MQ-9B Reaper drones, while Pakistan acquired an equivalent threat at nearly one-tenth of the price. This cost discrepancy has been a source of concern for India. Currently, US allies are compelled to choose expensive US-made drones, but oil-rich Middle Eastern countries have opted to purchase drones from China. Why is this the case? They are buying the right equipment, not the expensive one. Wealthy nations are not naive, and US allies are not either; they simply don’t want to jeopardize their political futures over such decisions.
US Media: F-35 Costs Three Times as Much as the J-20, How Will This Battle Be Fought?
On October 31st, a Twitter post by Godfree Roberts (@GodfreeTrh) claimed that the US F-35 is the world’s most expensive aircraft, costing three times as much as China’s J-20. The F-35 has a quarter of the range, a quarter of the payload, and half the missile range of the J-20. The F-35 cannot cruise at supersonic speeds, while the J-20 easily achieves supersonic cruising speeds.
What’s even more concerning for the US military is that the J-20’s two-seater version can already control loyal wingman drones for combat operations. The US military’s future combatants will only include unmanned drones without human pilots, a truly terrifying prospect. Many US netizens have expressed differing opinions on this matter, with some asserting that the US military’s technological equipment still leads globally.
I concur! The US military indeed boasts many cutting-edge high-tech weapons, but their exorbitant prices make them impractical. For instance, the F-35, Zumwalt-class destroyers, Littoral Combat Ships, and more are examples of expensive equipment that lacks practicality. Such cases are not rare in the US military. High-tech equipment in the US military is costly, and it channels a significant portion of military spending toward major defense contractors, resulting in extended development cycles and continued government funding, often at exorbitant prices. For instance, a single Standard Missile 3 (SM-3) ship-based air defense missile from Raytheon costs as much as $10 million, while a Russian Su-30MKI costs only around $40 million. This stark contrast in pricing showcases the significant cost disparities.
In 2022, the US Air Force’s Deputy Assistant Secretary for Procurement, Cameron Holt, publicly warned the US government that China’s defense procurement efficiency far exceeded that of the United States. This propelled the People’s Liberation Army’s (PLA) weapon and equipment development speed and modernization, which is now five to six times faster than that of the US military. While Holt’s warning may be somewhat exaggerated, it does reflect the low efficiency of the US military’s use of defense spending. In 2022, the US defense budget amounted to a staggering $782 billion, yet the US military still has numerous combat units operating in the digital era without undergoing information warfare reforms. In comparison, the PLA accomplished information warfare reforms for 2 million active-duty personnel in less than a decade, significantly enhancing its combat capabilities.
The reasons behind this situation can be attributed to two factors: corruption and the military-industrial complex. Corruption is evident in cases such as the exorbitant prices paid for coffee makers and USB interfaces for the US Air Force, with a single coffee maker costing as much as $1,280 and a USB conversion interface for a B-52 bomber priced at $2,800. These price tags raise questions about potential corruption and vested interests.
The military-industrial complex is another serious issue. The United States appears to be held hostage by this complex, which forces the country to engage in continuous warfare to generate profits for defense contractors. This compels the US military to seek perpetual warfare to drive the defense economy, with wars in the 1990s and early 2000s proving lucrative. However, the recent war on terror resulted in bloodshed and significant financial costs, contributing to a staggering increase in the US national debt from $5.6 trillion in 2000 to $33 trillion in 2023. At a current interest rate of 5.5%, the US must pay $1.7 trillion annually in interest alone, not including the principal amount.
This alarming situation is exacerbated by a significant portion of military spending flowing to major defense companies. These companies, in collaboration with external research and development organizations, inflate the cost of military equipment. This leads to prolonged development cycles, forcing the US government to continue funding these projects. For instance, the price of a single Standard Missile 3 (SM-3) ship-based air defense missile from Raytheon is as high as $10 million. In contrast, a Russian Su-30MKI costs only about $40 million, highlighting the substantial cost disparity.
Countries such as Ukraine and Middle Eastern nations are continuously draining the United States of its resources. The recent high-level meeting between the Chinese Foreign Minister and the US government provides a clear indication of the shifting balance of power. Over the past two years, the balance of power has shifted significantly, and the strength of the United States is much weaker than it was in previous years. The confrontational attitude of U.S. diplomats during the Alaska meeting of the past is still vivid in memory, but now they are engaged in friendly discussions at the White House with President Biden. Times change, and fortunes change, the situation in the United States has deteriorated significantly, as the Chinese saying goes, “The river to the east changes every thirty years, and the river to the west changes every thirty years.” The United States is declining. (Xing Chen)
