F-35 messed up and didn’t calculate the vortices in its wake

Bulgarianmilitary.com looks into a calamitous air crash of October 2022 in an effort to find out why it happened. Caliber.Az reprint the article.

In its definitive report, the US Air Force has shed light on the calamitous air crash that took place in October 2022. The aircraft involved was a Lockheed Martin F-35A Lightning II, a multirole fighter jet of notable distinction, which was regrettably obliterated upon impact.

The report delineates that the pilot, in a fortunate turn of events, was spared from the grim fate of the aircraft. This fortunate outcome was solely attributed to the activation of the ejection seat, a critical safety feature in such high-risk scenarios.

Financial implications of the incident are substantial, with a projected valuation reaching upwards of 166 million dollars, equating to roughly 151 million euros.

On October 19, as the evening shadows began to lengthen and the local time struck six, a quartet of F-35As were drawing their training mission to a close at Hill Air Force Base, situated in the rugged landscapes of Utah.

The execution of the flight mission transpired without any notable deviations, and as the squadron drew closer to the base, one aircraft took on the responsibility of assessing the meteorological conditions pertinent to landing at the base. This information was disseminated amongst the other aircraft in the formation, yet a critical detail was inadvertently overlooked: at the time of the incident, protocols for handling wake vortices were actively being implemented.

The phenomenon known as wake turbulence embodies the turbulent, unstable air that an aircraft leaves in its wake as it cuts through the sky.

As per the insights gleaned from the accident investigators, it was discernible, based on the prevailing meteorological conditions, that the pilots ought to have deduced the pertinence of the trailing vortex procedures. However, in a stark deviation from the expected course of action, the landing was executed by conventional methodologies.

The aircraft that tragically crashed was positioned a mere horizontal span of approximately 3,000–4,000 feet [roughly 900–1,200 m] away from its predecessor which was in descent. This distance was significantly less than the recommended 9,000 feet [approximately 2,700 m] which is typically adhered to to avoid the potential hazards of debris vortices. Consequently, the turbulence generated by the preceding aircraft had not sufficiently dissipated, thereby contributing to the unfortunate incident.

In the course of its final approach trajectory, the F-35 found itself navigating turbulent air for a trifling span of three seconds, precisely from 18:08:27 to 18:08:30 local time. It is noteworthy to mention that before this instance, the aircraft had valiantly traversed a similar stretch of turbulent air, emerging unscathed and fully operational.

On the second occasion, the vortices precipitated a complex predicament. The left multi-function sensor, tasked with quantifying the properties of airflow, plunged into a state of failure. Concurrently, the status of the right sensor oscillated unpredictably between normal functionality and failure mode.

In the vein of its contemporaries, the F-35 incorporates the celebrated Fly-By-Wire [FBW] system. This system is a high-tech marvel wherein the pilot’s control inputs are transmitted to a sophisticated onboard computer. Following this, the computer meticulously processes these inputs and subsequently dispatches the requisite commands to the aircraft’s control surfaces.

In the prevailing circumstances, the ADA [Air Data Application] software, responsible for interpreting sensor readings, experienced significant malfunctions. Hence, it dispatched erroneous instructions to the aircraft control surfaces. This essentially translates to the F-35 no longer being under the direct command of the pilot.

In the final report, the F-35 test pilot, observing the aircraft’s landing trajectory from the ground, provides an insightful account of his observations. He notes, “The aircraft’s control surfaces exhibited significant movements. This included the stabilizers, wing trailing edge flanges, and rudders, all of which were oscillating with unusual rapidity, likely at their maximum speeds.”

The test pilot, in his account, revealed that the aircraft abruptly entered a sideslip – a lateral movement that deviated from its intended path – of approximately 30 to 40 degrees. This behavior, he noted, is a significant deviation from standard performance parameters. The implication of this condition is that it effectively renders the aircraft uncontrollable. Ordinarily, the upper limit for a permissible sideslip is set at a relatively modest 8 degrees. Following this dramatic sideslip, the aircraft, almost predictably, veered sharply towards the left.

In the harrowing sequence of events leading to the plane crash, the pilot made a valiant attempt to regain control of the plummeting aircraft. Despite these efforts, the situation rapidly deteriorated. Consequently, at precisely 18:08:36, a mere nine seconds since the inception of the catastrophic chain of events, the pilot was compelled to activate the ejection seat.

The manifestation of contemporary rescue technology’s prowess is embodied in the ejection seat. At the moment of activation, the aircraft was merely approximately 200 feet – or around 60 meters – above terra firma, with a substantial leftward tilt.

Remarkably, the system demonstrated its efficacy by stabilizing and rectifying the divergent trajectory of the jumper. The canopy, in a display of normal functionality, unfurled as expected, facilitating a safe landing for the pilot. Sustaining only minor injuries from the endeavor, the pilot was promptly discharged from medical care on the very same evening.

In the wake of a comprehensive investigation, the board of inquiry has ascertained that the tragic accident was triggered by a malfunction in the aircraft’s control system. This defect caused the plane to veer off the pilot’s control just before it was due to land, rendering it impossible to rectify the situation in the remaining time.

As the researchers have duly noted, the F-35 fleet has an impressive record of over 600,000 hours of flight. They further stated that this is the first instance where debris vortices have been reported to cause issues of this nature.