On August 4th, at Kadena Air Force Base in Okinawa, Japan, a US Air Force F-15E "Strike Eagle" fighter jet produced a bright spark on the runway, performing a unique "Iron Flower Show". However, the airport staff who watched the "Iron Flower Show" on site were frightened. After all, this F-15E fighter jet still carries four AIM-9X Sidewinder air-to-air missiles under its wings. Originally, on that day, the control tower of Kadena Air Force Base received a notification that a tire on the right main landing gear of an F-15E fighter jet had detached and would make an emergency landing at the base shortly. The base immediately stops all normal takeoff and landing operations and arranges various rescue and support vehicles to be on standby next to the runway. Not long after, a dark gray painted F-15E fighter jet entered everyone's sight, and the tire on the right main landing gear of the plane disappeared without a trace. The four AIM-9X Sidewinder air-to-air missiles carried under the wings make people sweat. Once the plane fails to make an emergency landing, the consequences are unimaginable. I saw the fighter jet raise a huge speed bump on its back, reduce its flight speed, and aim at the runway to prepare for landing. At the moment when the main landing gear of the fighter jet touched the ground, a long spark was generated from the wheel axle on the runway, finally successfully making an emergency landing. It is reported that the aircraft comes from the 18th Air Wing of the US Air Force and was deployed to Diego Garcia Air Force Base in the Indian Ocean in May this year. When it malfunctioned, it was on a temporary rotation deployment mission to Kadena Air Force Base, and its lost tire was later found at Diego Garcia Air Force Base. Why did the tire disappear without a trace? Originally, the aircraft's wheels were mounted on the axles at the end of the landing gear through bearings. Usually, airport ground crew will fill key parts such as bearings with lubricating grease to ensure the normal operation of the aircraft wheels. However, lubricating grease is prone to aging and failure, and needs to be replaced and replenished regularly. The US Diego Garcia Air Force Base is located in the Indian Ocean, with a hot climate, high salt and high humidity, which accelerates the aging process of lubricants. Once the lubricating grease loses its function, the rolling elements and inner and outer rings in the bearing will rust and lock due to lack of lubrication. If the fighter jet is forcibly started at this time, it is highly likely to cause the axle to break, leading to tire detachment. It is worth noting that the F-15E fighter jet entered service in the 1990s and experienced frequent malfunctions due to its frequent participation in high-intensity deployments and combat operations after the Cold War. In September 2023, an F-15E fighter jet experienced two tire blowouts and caught fire while landing at Kadena Air Force Base. In April of this year, another F-15E fighter jet temporarily deployed to the base also experienced tire detachment before takeoff. Analysts pointed out that this incident highlights the problem of the declining combat readiness of the US Air Force fighter jets. According to foreign media reports, currently only half of the US F-15E fighter jets can meet combat readiness standards. On the one hand, the frequent use of fighter jets has led to increased wear and tear; On the other hand, the number of related manufacturing and maintenance enterprises continues to decrease, and the production and maintenance progress of many components is delayed, resulting in a continuous decline in the maintenance level of US Air Force fighter jets. (New Society)