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By NASA
A chevron nozzle is installed on NASA’s Learjet for a mid-March 2001 flight test at Lorain Country Airport to verify that in an emergency, the aircraft could be flown using only the experimental engine. Credit: NASA/Marvin Smith
Shortly after dawn on March 27, 2001, NASA pilot Bill Rieke took off from an airfield just outside of Phoenix in NASA’s blue-and-white Learjet 25 and flew low over a series of microphones for the first flight test of a groundbreaking NASA technology.
On one of the plane’s engines was an experimental jagged-edged nozzle that researchers at Glenn Research Center in Cleveland had discovered made aircraft significantly quieter. These initial flight tests were an important step toward using these “chevron nozzles” on modern aircraft, lowering noise levels for communities.
NASA Glenn has been exploring ways of reducing engine noise since the first jet airliners appeared in the 1950s. New turbofan engines in the 1960s were quieter, but the expansion of the overall airline industry meant that noise was still an issue. With the introduction of noise-limiting mandates in the 1970s, NASA and engine manufacturers embarked on a decades-long search for technologies to lower noise levels.
NASA researchers discovered that the military’s use of rectangular notches, or tabs, along an engine nozzle’s exit – to help disguise a jet fighter’s infrared signature – could also reduce engine noise by helping mix the hot air from the engine core and the cooler air blowing through the engine fan. In the 1990s, Glenn researcher Dennis Huff and his colleagues discovered that a serrated, or sawtooth, shape, referred to as a chevron, offered more promise.
Dennis Huff explains chevron nozzles, seen on a table, to U.S. Senator George Voinovich and other visitors inside the Aero-Acoustic Propulsion Laboratory facility in 2006. Huff was head of NASA Glenn Research Center’s Acoustics Branch at this point.Credit: NASA/Marvin Smith NASA contracted with General Electric and Pratt & Whitney to develop an array of tab and chevron designs to be analyzed in Glenn’s unique Aero-Acoustic Propulsion Laboratory (AAPL). Extensive testing in the spring of 1997 showed the possibilities for reducing noise with these types of nozzles.
Engine manufacturers were impressed with the findings but wary of any technology that might impact performance. So, in 1998, NASA funded engine tests of the 14 most promising designs. The tests revealed the chevron nozzle had a negligible 0.25% reduction of thrust. It was a major development for jet noise research.
In September 2000, Glenn’s Flight Operations Branch was contacted about the logistics of flight-testing chevron nozzles on the center’s Learjet 25 to verify the ground tests and improve computer modeling. Nothing further came of the request, however, until early the next year when Huff informed Rieke, chief of Flight Operations, that the researchers would like to conduct flight tests in late March—with just eight weeks to prepare.
Glenn’s Acoustics Branch worked with colleagues at NASA’s Langley Research Center in Hampton, Virginia, and the Arizona-based engine manufacturer Honeywell on the effort. They planned to conduct testing at Estrella Sailport just outside of Phoenix from March 26 to 28, 2001.
Bill Rieke and Ellen Tom with the chevron nozzle installed on the Learjet. NASA Glenn Research Center’s small Flight Operations team was heavily involved with icing research and solar cell calibration flights during this period, so arrangements were made for Tom, a Federal Aviation Administration pilot, to assist with the chevron flights. Credit: Courtesy of Bill Rieke With the required safety and design reviews, the eight-week target date would be difficult to meet for any test flight, but this one was particularly challenging as it involved modifications to the engine nacelle. While the special nozzle engineers created for the flights would allow them to switch between a six- and a 12-chevron design during testing, it also got hot quickly. This necessitated the installation of new sensors, rewiring of fire alarm cables, and the presence of an onboard test engineer to monitor the temperatures. The short turnaround also required expedited efforts to obtain flight plan approvals, verify the plane’s airworthiness, and perform normal maintenance activities.
Despite the challenges, Rieke and a small team delivered the Learjet to Estrella on March 25, as planned. The next day was spent coordinating with the large Langley and Honeywell team and acquiring baseline noise data. The pilots idled the unmodified engine as the Learjet flew over three perpendicular rows of microphones at an altitude of 500 feet and speed of 230 miles per hour.
View from below as NASA Glenn Research Center’s Learjet 25 passes overhead at the Estrella airfield with the experimental chevron nozzle visible on the left wing.Credit: Courtesy of Bill Rieke The flight patterns were repeated over the next two days while alternately using the two variations of the chevron nozzle. The researchers anecdotally reported that there was no perceptible noise reduction as the aircraft approached, but significant reductions once it passed. Recordings supported these observations and showed that sideline noise was reduced, as well.
The flights of the Learjet, which was powered by a variation of GE’s J-85 turbojet, were complemented by Honeywell’s turbofan-powered Falcon 20 aircraft. These flights ultimately confirmed the noise reduction found in earlier AAPL tests.
Overall, the flight tests were so successful that just over a year later the FAA began certifying GE’s CF34–8, the first commercial aircraft engine to incorporate chevron technology. The engine was first flown on a Bombardier CRJ900 in 2003. Continued studies by both NASA and industry led to the improved designs and the incorporation of chevrons into larger engines, such as GE’s GEnx.
According to Huff, the chevron’s three-decibel noise decrease was analogous to the difference between running two lawnmowers and one. Their comparatively easy integration into engine design and minimal effect on thrust made the chevron a breakthrough in noise-reduction technology. In 2002, NASA presented an innovation award to the Glenn, Langley, and Honeywell team that carried out the flights. Today, airliners such as the 737 MAX and 787 Dreamliner use chevron nozzles to lower noise levels for communities near airports.
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By USH
EBANI stands for "Unidentified Anomalous Biological Entity," referring to a mysterious class of airborne phenomena that may be biological rather than mechanical in nature. These entities are often described as elongated, flexible, and tubular, moving through the sky in a serpentine or twisting manner.
They exhibit advanced flight capabilities, including high-speed travel, precise control, and even self-illumination. Some have been observed rendering themselves invisible, raising questions about their energy sources and possible technological origins.
Recent observations have revealed formations of translucent spheres in red, white, and blue, challenging conventional classifications of both biology and aerodynamics.
Some of these entities have a massive structure composed of thousands of clustered spheres. These entities appear to function as an aircraft carrier, releasing these smaller spheres into Earth's atmosphere for an unknown purpose.
While some researchers propose that EBANIs are natural organisms evolving in Earth's upper atmosphere under unfamiliar physical laws, others speculate they may be advanced artificial (eventually biological) constructs, potentially extraterrestrial probes or surveillance devices, given the presence of large structures expelling numerous smaller spheres.
Are they living UFOs, advanced biological organisms that function autonomously within the spheres, without the need for pilots?
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By USH
On January 25, 2025, an Oklahoma City man recorded a baffling UFO that he described as a "plasma-filled jellybean." A concerned neighbor also spotted something unusual in the sky and soon, the entire neighborhood gathered outside, to witness the anomaly.
The mysterious object emitted a glow and moved erratically, mesmerizing onlookers. In his recorded footage, Frederick can be heard narrating the event. "I don’t hear anything, and it's moving unpredictably," he noted. "It looks like a jellybean, but the interior appears to be plasma."
Frederick decided to launch his drone for a closer look, but upon attempting to deploy his drone, he encountered unexplained technical failures. "My controller provides voice notifications," he explained. "It repeatedly announced, ‘unable to take off, electromagnetic interference."
After multiple attempts, he finally got the drone airborne, reaching approximately 1,000 feet beneath the UFO. However, just after capturing three images, the drone’s video function failed, and its battery, despite being fully charged, suddenly drained. "It had a 35-minute flight time," Frederick stated. "But right after taking those three pictures, the controller alerted me: ‘low battery, return to home."
Seeking expert insight, Frederick shared his footage and images with University of Oklahoma physics professor Mukremin Kilic. When asked about the sighting, Kilic remarked, "I don’t know what it is" and suggested the object was likely a drone. However, this theory does not explain why Frederick’s own drone experienced interference, raising further questions about the true nature of the UFO.
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By USH
The American Meteor Society website shared a video on their channel showing a fireball streaking across the skies of Michigan and Ohio on Sunday, January 19, 2025, around 01:31 UT.
Though, Meteor Society noted that the video might not actually depict a fireball event, leaving some viewers curious about the meaning behind this statement.
At the moment the fireball appears on camera, a strange object seems to materialize above it, expanding in size and partially obscuring the fireball before gradually fading out as the fireball continues its path through the sky.
This phenomenon has sparked varied interpretations. Some suggest it might indicate alien intervention, while others offer a more plausible explanation: the "object" is likely a water droplet on the camera lens, creating the illusion of interaction with the fireball.
However, since the Meteor Society suggested that it might not actually depict a fireball event, we might question whether it was truly a fireball, a meteor, including a water droplet, or something entirely different.
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By USH
In December 2024, reports began surfacing about strange events involving flashing streetlights house and building lights. These incidents, initially dismissed as isolated cases, have now been observed on a larger scale, spanning countries such as the U.S., Canada, and the UK.
Some observers theorize that drones or unidentified orbs might be responsible. These objects could emit electromagnetic interference, disrupting electrical systems and causing lights to flicker. However, no concrete evidence has linked these phenomena to drone activity.
Others suggest the lights could be a result of hackers targeting the power grid. Cybercriminals might be testing infrastructure vulnerabilities. While plausible, no definitive proof has emerged to support this explanation.
A more unconventional theory suggests that the flashing lights are a result of a phenomenon known as Streetlight Interference (SLI). Proponents argue that certain individuals, nicknamed "SLIders," possess psychic or psychokinetic abilities that unintentionally influence lighting systems. SLI remains scientifically unverified, with no successful replication in controlled settings.
Some experts believe it might be mechanical faults in the electrical systems or or fluctuations in the power supply. However, this theory seems unlikely due to the widespread and simultaneous nature of the phenomenon, which has been reported across multiple countries, suggesting it is not a localized issue.
Or is this phenomenon linked to extraterrestrial activity? Some argue that aliens might use electromagnetic propulsion systems, potentially interfering with electrical systems, akin to the effects portrayed in films like 'Close Encounters of the Third Kind'.
Could the cause of these flashing lights be a harbinger of an impending global or cosmic event, or might it stem from something entirely beyond our understanding?
The two videos below show, besides the on going mysterious drones/UFO/orb sightings, several locations where street lights are flashing.
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