​ZeroAvia and PowerCell are expanding their joint work on fuel cell technology with a view to meeting higher energy needs of hydrogen-powered fixed-wing aircraft and rotorcraft. The companies, which have been collaborating since 2022, signed a new memorandum of understanding on October 29, announcing that they will work on next-generation fuel cells for hydrogen-electric powertrains.
Sweden-based PowerCell is already providing fuel cells for the 600-kilowatt ZA600 propulsion system that ZeroAvia is developing for aircraft with up to 20 seats. It submitted a certification application for the ZA600 unit in late 2023.
These low-temperature proton exchange membrane fuel cells form part of a multi-stack powertrain architecture that ZeroAvia is now scaling up for the 2-megawatt ZA2000 system. This is intended for airliners with between 40 and 80 seats, such as the ATR72 and Dash 8 Series 400.
3kW/kg Power Density Coming SoonAccording to ZeroAvia, it has already achieved a power density of above 2.5 kilowatts per kilogram. The company, which has engineering teams in both the U.S. and UK, said it is on track to exceed 3 kW/kg in the next few months.
One key objective is to increase the operating temperature of fuel cells to reduce the amount of cooling and humidification needed. ZeroAvia said this would simplify the required powertrain architecture and improve the amount of power generated for a given unit of weight.
“We’re confident that the first hydrogen-electric aircraft will be flying commercially in the upcoming years,” said PowerCell CEO Richard Berkling. “When that happens, it will have a snowball effect as the environmental and operating cost benefits become clear to airlines and their passengers. For PowerCell, this is a key future market, and we are delighted to be deepening our partnership with the leader in this space to develop solutions to enable more clean flights, removing emissions.”

ANKARA, Oct 23 (Reuters) - Two attackers killed five people and wounded 22 others on Wednesday in what Ankara called a terrorist attack at the Turkish Aerospace Industries headquarters, where witnesses said they heard gunfire and an explosion.
Interior Minister Ali Yerlikaya said both attackers were killed after the attack, adding two of the injured are in critical condition. TV broadcasters showed footage of armed assailants entering the TUSAS building near Ankara. "Two terrorists were neutralised in the terror attack on the TUSAS Ankara Kahramankazan site," Yerlikaya said.
"Sadly, we have five martyrs and 22 wounded in the attack. Three of the injured were already discharged from hospital, 19 of them under treatment," he said.
Yerlikaya said the perpetrators were "highly likely" members of the outlawed Kurdistan Workers' Party (PKK).
"The style of the act shows that it is highly likely the PKK that carried out the attack. Once identification is completed and other evidence become clearer, we will share more concrete information with you," he said.
Turkish air forces conducted airstrikes in northern Iraq and northern Syria and destroyed 32 PKK targets, the defence ministry said late on Wednesday, adding that many PKK members were killed.

Prosecutors have launched an investigation, state-run Anadolu Agency reported.
Turkish President Tayyip Erdogan, alongside Russia's Vladimir Putin at a BRICS conference in the Russian city of Kazan, condemned the attack and accepted Putin's condolences. NATO, the United States and the European Union also condemned the attack.​

Witnesses told Reuters that employees inside the building had been taken to shelters by the authorities and no one had been permitted to leave for a few hours. They said the blasts they heard may have taken place at different exits as employees were leaving work for the day.
Witnesses later said evacuation of personnel from the TUSAS campus had started and buses were allowed to leave as the operation had ended.
Broadcasters showed images of a damaged gate and footage of an exchange of gunfire in a parking lot, as well as the two attackers carrying assault rifles and backpacks as they entered the building. Ambulances and helicopters later arrived.
TUSAS is Turkey's largest aerospace manufacturer, currently producing a training craft, combat and civilian helicopters, as well as developing the country's first indigenous fighter jet, KAAN. Owned by the Turkish Armed Forces Foundation and the government, it employs more than 10,000 people.
NATO Secretary General Mark Rutte condemned the attack and said the military alliance would stand with its ally Turkey.

After the world posted its worst year for wildfires, with an area roughly the size of Nicaragua scorched in 2023, one plane model has become the most important aircraft on Earth.   A specialized amphibious firefighting plane — commonly called a Canadair after its original manufacturer — is unique in the market for its size and maneuverability. It can hold as much as 1,621 US gallons (6,137 liters) of water — about 20 bathtubs full — and travel at more than 200 miles per hour (322 kilometers per hour). In a quick swoop, the planes scoop up water from lakes or seas — filling up in 12 seconds — and fly as low as 100 feet (30 meters) above burning infernos to douse flames.

​As climate change makes wildfires more frequent and intense around the world, these acrobatic water-bombers are needed now more than they’ve ever been before. Yet they were out of production for almost 10 years. This has now changed.


De Havilland Aircraft of Canada Ltd., which acquired the rights to the aircraft in 2016, reached new agreements with European Union countries this year to provide 22 DHC-515 firefighter planes, the brand successor of the Canadair. The order will be the first time De Havilland makes these €50 million ($55 million) planes. While production won’t finish until the end of 2026 at the earliest, the EU is willing to wait for a firefighting plane considered incomparable to anything else available.


“The so-called Canadair is the only functioning, operational aircraft in that category in this moment of time,” Hans Das, deputy-director general for European civil protection and humanitarian aid operations at the European Commission, said in an interview. “Over the last few years, we have seen forest fires expanding into all of Europe. Nobody escapes anymore.”

Wildfires have been raging across the continent this year — most ferociously in Greece and Turkey — as the world recorded its hottest summer ever. Across the Atlantic, Brazil’s Amazon rainforest has been on fire, wafting toxic smoke into the country’s largest city Sao Paulo in recent weeks. In North America California battled one of its worst wildfires on record in July and blazes have raged across De Havilland’s home province of Alberta. Fires were still smoldering under the snow in Canada in March after unprecedented wildfires in 2023.


Most firefighters are on the ground during a wildfire, but planes play an important role in helping dowse fires with water or stopping the spread with retardant.


“As fires continue to increase both in number of fires and in the scale, there is just more and more need for aerial firefighting assets to help support those firefighters on the ground so they don’t get their butt kicked,” Paul Petersen, executive director of the United Aerial Firefighters Association, said in an interview.


Petersen estimates the world needs twice the amount of firefighting aircraft currently available to meet demand.


Riva Duncan, a retired fire chief with the US Forest Service, agreed that demand has been exceeding aircraft availability. “The growing number of fires we’re having, the lengthening of the fire season into a fire year, larger, more destructive fires — we need every tool in the toolbox to be able to manage these fires and aircraft’s a big part of that,” she said. 


Quebec-based Bombardier Inc., the previous manufacturer of the Canadair planes, sold off the unit in 2016 as it dealt with a series of financial difficulties. From 2015 until the new EU order, the firefighter planes had been out of production.


De Havilland first discussed restarting production of the planes in 2019, but due to the high costs, it needed a firm commitment of a minimum number to get their suppliers on board for parts, according to Neil Sweeney, De Havilland vice president of corporate affairs. He said the EU’s order for 22 planes was enough to start things up again.


The EU started looking at expanding its aerial firefighting fleet in 2020 — taking on board supply chain lessons learned during the Covid pandemic. With fires happening simultaneously across the continent, the bloc found sharing resources across countries does not work if there aren’t enough planes.
​

“When everybody is facing the same difficulty, then the system gets paralyzed,” Balazs Ujvari, a spokesperson for the European Commission, said in an interview. “If your house is burning then you cannot also help the neighbor’s house that is burning.”


For this fire season, the EU has access to 26 firefighting planes from nine member states.


De Havilland said there are approximately 160 Canadair planes in operation in 10 countries: Turkey, Morocco, Canada, the US, France, Croatia, Spain, Italy, Greece and Malaysia. There are other aircraft capable of water bombing, but they either hold less extinguishing agent or they’re good for one big drop before needing to return to a station for a slower refill. Canadairs, on the other hand, can circle back and skim an open body of water again and again, refilling almost at full speed. 


While countries around the world have made regional deals to share aerial firefighting resources, including lending out aircraft during off-seasons for wildfires, climate change has been making this a logistical nightmare. Countries are dealing with longer fire seasons and places that previously didn’t have many fires are seeing them more regularly.


This is one reason De Havilland expects to see more demand for firefighting aircraft in the future. The other is that many countries will be keen to upgrade aircraft in their fleet — which may be up to 50 years old. Over time, planes that scoop salt water can suffer from corrosion, and in warmer climates they may begin to rust.


The new DHC-515 aircraft will have similar water capacity to its predecessor, but will have a few upgrades. These include improvements to the water drop control system, the avionics, the rudder control and the air conditioning. 


Mike Flannigan, a research chair in emergency management and fire science at Thompson Rivers University, said De Havilland may have cornered a market for these types of planes now, but other manufacturers will likely sense an opportunity as wildfires become a more difficult problem for countries to tackle.


“I expect they might get some competition eventually if this market continues to grow,” he said.

Russians are getting really fed up with the Ukrainian crew of that Yakovlev Yak-52 training plane that has been dogfighting with, and shooting down, Russian surveillance drones—World War I-style. A Russian drone operator's view of the Ukrainian Yak-52 and its back-seat gunner.
RUSSIAN MILITARY CAPTURERussians are getting really fed up with the Ukrainian crew of that Yakovlev Yak-52 training plane that has been dogfighting with, and shooting down, Russian surveillance drones—World War I-style.
In three months, two aviators riding in a Yak-52—a front-seat pilot and a back-seat gunner—have taken out at least 12 Russian drones, if you believe the kill markings the crew has painted on the side of the 1970s-vintage plane.
“Isn’t it time to shoot him down?” one Russian blogger wrote.
The problem for the Russians is that a Yak-52 is hard to knock down for the same reason it’s an effective platform for a shotgun-armed crew member taking potshots at nearby drones. The Yakovlev is robust and inconspicuous.
A propeller-driven Yak-52 doesn’t paint a very big picture on the radar screens of Russia’s beleaguered long-range air defense batteries. And even if you damage a Yak-52 by, say, ramming it with a drone—the crew could probably still land the plane.
Earlier this month, another Russian blogger complained about the Yak-52 crew “firing at our UAVs like it’s a shooting gallery” over the city of Odesa in southern Ukraine.
It wasn’t a new problem. Apparently searching for an efficient method of eliminating $100,000 Russian drones without firing a $4-million Patriot missile or some other pricey air defense munition, back in April the Ukrainians began taking to the air in that Yak-52, maneuvering to within shotgun range of intruding drones—and blasting them out of the air.

It worked so well that, earlier this month, the Ukrainian intelligence directorate began training gunners to hunt Russian unmanned aerial vehicles from locally-made Aeroprakt A-22 sport planes. The Yakovlev crew’s successful hunts have inspired a whole new anti-drone tactic.
The Russians are losing patience as their losses pile up. “The Yak-52 flew over Odessa and with high efficiency shot down our reconnaissance UAVs for a week, causing laughter in some circles,” the blogger wrote. “This has not been funny to UAV operators and us for a long time.”
But it’s not clear what the Russian military can do about the Yak-52. Its patrol zone is at least 50 miles from the nearest Russian position. Yet the closest Russian air defense batteries are probably much farther away, as Ukrainian drone and missile raids continue to deplete their numbers and drive them farther from the front line.
In any event, a Yak-52 might be tough to detect. One 1976 study found that a Cessna 172—a propeller plane similar to a Yak-52 in size and shape—presents a radar cross-section of less than a square meter from certain angles. That’s a quarter the radar cross-section of a typical fighter jet.
The Russian operators of the very drones the Yak-52 crew has been hunting could try to ram the Ukrainian plane. It wouldn’t be unprecedented. On many occasions in Russia’s 28-month wider war on Ukraine, Russian and Ukrainian crews have downed enemy drones by running their own drones into them.
But it’s one thing for two drones each weighing just a few pounds to tangle in mid-air: either could destroy the other. But smash a 20-pound ZALA surveillance drone into a 1.5-ton Yak-52 and the damage might not be catastrophic.

NASA and Boeing said a helium leak in Boeing's Starliner spacecraft was "stable" and wouldn't prevent two astronauts from launching into space next week in a mission more than a decade in the making.
NASA and Boeing execs said in a press conference on Friday that the cause of a leak in Starliner's propulsion system had been identified and that it was safe to fly.
A launch attempt on May 6 was scrubbed hours before takeoff because of a separate issue, after which a "small" leak was discovered on a flange on one of Starliner's thrusters, said Steve Stich, a NASA program manager.

Mark Nappi, a Boeing vice president, said that days after the leak was discovered, "we proved to ourselves that the leak was stable." He said the "design vulnerability" was "very remote" and "not a safety-of-flight issue."
Stich said, "We can handle up to four more leaks, and we can handle this particular leak if that leak rate were to grow even up to 100 times."
Boeing's Starliner is set to take two NASA astronauts, Butch Wilmore and Suni Williams, to the International Space Station on June 1 and then back after one week. There are backup launch opportunities on June 2, 5, and 6.
Boeing is playing catch-up with SpaceX, whose Dragon spacecraft has been transporting astronauts to and from the ISS since 2020. Starliner's voyage comes amid scrutiny of Boeing's safety culture around its separate passenger-plane division.
Starliner encountered issues on uncrewed test flights in 2019 and 2021.
Spokespeople from both Boeing and NASA referred DOA to Friday's press conference.

Like Tom Cruise's "Maverick" character in "Top Gun," Boom Supersonic is feeling the need for speed.
The Colorado company has received a first-of-its-kind approval from the U.S. Federal Aviation Administration (FAA) to exceed Mach 1 during test flights of its XB-1 supersonic jet. These flights are slated to occur sometime this year within the Black Mountain Supersonic Corridor in Mojave, California.
The sleek, delta-shaped XB-1 took its maiden flight on March 22, 2024 from the Mojave Air & Space Port, and now it's free to go supersonic at Boom's California complex when fully ready.
"Following XB-1's successful first flight, I'm looking forward to its historic first supersonic flight," said Blake Scholl, founder and CEO of Boom Supersonic. "We thank the Federal Aviation Administration for supporting innovation and enabling XB-1 to continue its important role of informing the future of supersonic travel."

This next phase of test flights will play out inside the Black Mountain Supersonic Corridor, as well as a segment of the nearby High Altitude Supersonic Corridor within the designated R-2515 airspace, an area well known for research and military supersonic aeronautical operations.
During the XB-1's inaugural mission last month, the jet was piloted by Boom Chief Test Pilot Bill "Doc" Shoemaker, while Test Pilot Tristan "Geppetto" Brandenburg was at the controls of a T-38 Talon chase aircraft, which observed and monitored the XB-1 for safety while aloft. 
"Being in the air with XB-1 during its maiden flight is a moment I will never forget," said Brandenburg in a Boom press statement. "The team has been working hard to get to this point, and seeing [that] flight through mission completion is a huge accomplishment for all of us."


Now the team is eager to conduct a second flight, which will test the jet's landing gear, among other hardware.
"We anticipate taking it up to 16 degrees AOA (angle of attack), and will also evaluate the sideslip, which will expand the envelope in order to give us a little bit more margin on a nominal landing," Brandenburg said. "It will also be the first time the 'dampers' — or stability augmentation system — is used."
Boom plans to expand the XB-1's flight envelope prior to going supersonic, to analyze performance and handling abilities through and beyond Mach 1. Ten to 20 "hops" are in order prior to any milestone supersonic jaunts over the desert, company representatives said.
"Right now, the plan is multiple supersonic flights. We plan to do Mach 1.1, 1.2, and 1.3 on the first three," Brandenburg said. "The reason for that is each one of those points takes so much airspace that you only have time to do one of them, so we will be on condition for several minutes; we'll get a flying qualities and handling qualities block, and have to come back home."

The iconic U-2 spy plane has many distinct characteristics like its deep black paint, but one of Beale Air Force Bases Dragon Lady’s is showing off it silver underskin.
TU-2S 1078, the “T” standing for trainer, is back in the skies after more than two years on the ground as it underwent a series of repairs and regular maintenance, according to Beale AFB. During its time in the repair bay, 1078 had its iconic black paint stripped off, exposing its silver body panels.
Even though 1078 is back in the sky, it still needs to undergo a series of airworthiness tests before receiving a fresh coat of black paint.
Beale AFB said the trainer aircraft is about halfway through the reintroduction process before trainers and trainees can hop back in.
​Beale, located in Yuba County, is the only United States Air Force Base operating the U-2 Dragon Lady and hosts the entire inventory of U-2S and T-U2S.

The U.S. military’s first war ace since Vietnam is fighting an enemy his predecessors couldn’t have imagined. Marine Capt. Earl Ehrhart has shot down seven explosives-packed suicide drones with his Harrier jump jet in the Navy’s effort to keep Red Sea shipping lanes open. The military defines an ace as any crew member whose aircraft has shot down five enemy aircraft. “I never imagined I was going to be doing this when we launched,” Ehrhart told the BBC, which was granted a tour of the USS Bataan, one of dozens of ships involved in the Red Sea operation.
Ehrhart told BBC the force is under constant threat of attack from Houthi rebels who began attacking merchant ships in December. The Bataan is actually an amphibious assault ship designed to rapidly deploy fully equipped fight forces to conflict areas. It pivoted to an air defense vessel with some outside-the-box thinking by its crew. “We took a Harrier jet and modified it for air defence,” Ehrhart told the BBC. “We loaded it up with missiles and that way were able to respond to their drone attacks.” The ship picks up the drones on its sensors and Ehrhart heads off in a one-sided pursuit. “They are shooting at us all the time, so we need to be even more focused. Our systems need to be primed so we can stay safe.”

Voyager 1 is still alive out there, barreling into the cosmos more than 15 billion miles away. However, a computer problem has kept the mission's loyal support team in Southern California from knowing much more about the status of one of NASA's longest-lived spacecraft.
The computer glitch cropped up on November 14, and it affected Voyager 1's ability to send back telemetry data, such as measurements from the spacecraft's science instruments or basic engineering information about how the probe was doing. So, there's no insight into key parameters regarding the craft's propulsion, power, or control systems. 


"It would be the biggest miracle if we get it back. We certainly haven't given up," said Suzanne Dodd, Voyager project manager at NASA's Jet Propulsion Laboratory, in an interview with Ars. "There are other things we can try. But this is, by far, the most serious since I’ve been project manager."
Dodd became the project manager for NASA's Voyager mission in 2010, overseeing a small cadre of engineers responsible for humanity's exploration into interstellar space. Voyager 1 is the most distant spacecraft ever, speeding away from the Sun at 38,000 mph (17 kilometers per second).
Voyager 2, which launched 16 days before Voyager 1 in 1977, isn't quite as far away. It took a more leisurely route through the Solar System, flying past Jupiter, Saturn, Uranus, and Neptune, while Voyager 1 picked up speed during an encounter with Saturn to overtake its sister spacecraft.
For the last couple of decades, NASA has devoted Voyager's instruments to studying cosmic rays, the magnetic field, and the plasma environment in interstellar space. They're not taking pictures anymore. Both probes have traveled beyond the heliopause, where the flow of particles emanating from the Sun runs into the interstellar medium.
There are no other operational spacecraft currently exploring interstellar space. NASA's New Horizons probe, which flew past Pluto in 2015, is on track to reach interstellar space in the 2040s.

State-of-the-art 50 years agoThe latest problem with Voyager 1 lies in the probe's Flight Data Subsystem (FDS), one of three computers on the spacecraft working alongside a command-and-control central computer and another device overseeing attitude control and pointing.
The FDS is responsible for collecting science and engineering data from the spacecraft's network of sensors and then combining the information into a single data package in binary code—a series of ones and zeros. A separate component called the Telemetry Modulation Unit actually sends the data package back to Earth through Voyager's 12-foot (3.7-meter) dish antenna.
In November, the data packages transmitted by Voyager 1 manifested a repeating pattern of ones and zeros as if it were stuck, according to NASA. Dodd said engineers at JPL have spent the better part of three months trying to diagnose the cause of the problem. She said the engineering team is "99.9 percent sure" the problem originated in the FDS, which appears to be having trouble "frame syncing" data.

So far, the ground team believes the most likely explanation for the problem is a bit of corrupted memory in the FDS. However, because of the computer hangup, engineers lack detailed data from Voyager 1 that might lead them to the root of the issue. "It's likely somewhere in the FDS memory," Dodd said. "A bit got flipped or corrupted. But without the telemetry, we can't see where that FDS memory corruption is."
When it was developed five decades ago, Voyager's Flight Data Subsystem was an innovation in computing. It was the first computer on a spacecraft to make use of volatile memory. Each Voyager spacecraft launched with two FDS computers, but Voyager 1's backup FDS failed in 1981, according to Dodd.
The only signal Voyager 1's Earthbound engineers have received since November is a carrier tone, which basically tells the team the spacecraft is still alive. There's no indication of any other major problems. Changes in the carrier signal's modulation indicate Voyager 1 is receiving commands uplinked from Earth.
"Unfortunately, we haven't cracked the nut yet, or solved the problem, or gotten any telemetry back," Dodd said.

Breaking out the bindersIn the next few weeks, Voyager's ground team plans to transmit commands for Voyager 1 to try to isolate where the suspected corrupted memory lies within the FDS computer. One of the ideas involves switching the computer to operate in different modes, such as the operating parameters the FDS used when Voyager 1 was flying by Jupiter and Saturn in 1979 and 1980. The hope among Voyager engineers is that the transition to different data modes might reveal what part of the FDS memory needs a correction.
This is a lot more complicated than it might seem on the surface. For one thing, the data modes engineers might command Voyager 1 into haven't been used for 40 years or more. Nobody has thought about doing this with Voyager's flight data computer for decades.
Voyager 1 and 2 have an outsized public profile compared to the resources NASA commits to keeping the spacecraft going. Fewer than a dozen people typically work on the Voyager mission. This number has slightly increased since the computer problem appeared in November, with a small "tiger team" of around eight experts in flight data systems, software, and spacecraft communications assigned to help troubleshoot the glitch.
"Not to be morose, but a lot of Voyager people are dead," Dodd said. "So the people that built the spacecraft are not alive anymore. We do have a reasonably good set of documentation, but a lot of it is in paper, so you do this archaeology dig to get documents."
Imagine rummaging through a user's manual for an antique car. The book's weathered pages are probably fraying. That's not unlike what Voyager engineers, some of whom weren't alive when the mission launched, are experiencing now.
"We have sheets and sheets of schematics that are paper, that are all yellowed on the corners, and all signed in 1974," Dodd said. "They’re pinned up on the walls and people are looking at them. That's a whole story in itself, just how to get to the information you need to be able to talk about the commanding decisions or what the problem might be."

This is a familiar task for Voyager engineers. In the last few years, the mission's core team at JPL has consulted archived documents to troubleshoot other, less serious computer problems and develop a new way to operate thrusters on both spacecraft to stave off the accumulation of residue in fuel lines.
While spacecraft engineers love redundancy, they no longer have the luxury of backups on the Voyagers. That means, in any particular section of the spacecraft, a failure of a single part could bring the mission to a halt. Both spacecraft run off nuclear batteries, which produce a little less electricity each year as their plutonium power sources decay. Toward the end of the 2020s, the declining power will force NASA to start turning off instruments on each spacecraft.
Most of NASA's modern missions exploring the Solar System have simulators on the ground to test commands and procedures before sending them to the real spacecraft. This practice can reveal commanding errors that could put a mission at risk.
“It is difficult to command Voyager," Dodd said. "We don't have any type of simulator for this. We don't have any hardware simulator. We don't have any software simulator... There's no simulator with the FDS, no hardware where we can try it on the ground first before we send it. So that makes people more cautious, and it's a balance between getting commanding right and taking risks."
Managers are also aware of Voyager 1's age. It's operating on borrowed time. "So we don't want to spend forever deciding what we want to do," Dodd said. "Something else might fail. The thrusters might fail. We want to do the right thing, but we can't hem and haw over what the right thing is. We need to look at things methodically and logically, and make a decision and go for it."
When it comes time to send up more commands to try to save Voyager 1, operators at JPL will have to wait more than 45 hours to get a response. The spacecraft's vast distance and position in the southern sky require NASA to use the largest 230-foot (70-meter) antenna at a Deep Space Network tracking site in Australia, one of the network's most in-demand antennas.
"The data rates are very low, and this anomaly causes us not to have any telemetry," Dodd said. "We're kind of shooting in the blind a little bit because we don't know what the status of the spacecraft is completely."

The F-15 twin-engine, high-performance, all-weather air superiority fighter became operational in November 1974 as the first aircraft in the US Military arsenal that could accelerate in a vertical climb. It was also the airplane that outpaced the Saturn V moon rocket when climbing to an altitude of 100,000 feet (just over 30,000 meters). After they got their hands on the first batch of combat-ready F-15s in late 1974, the top hats of the United States Air Force realized that the fastest PR stunt the new fighter could pull would be to smash aviation records. By January 1975 – less than two months after its commissioning – the aircraft was dropping previous world records like bowling pins.

The major race was not against its predecessor, the F-4 Phantom, but aimed at the perennial cold-war rival, the Soviet Union. Specifically, the MiG-25 Foxbat - the 3.2-Mach capable fighter developed to hunt down the legendary SR-71 Blackbird. The Soviet warplane was considered a severe threat to the best U.S. fighters of the era, and the F-15 was updated to match the MiG.

However, without a direct, head-to-head confrontation, the next best tool to assess the newly launched ‘Strike Eagle’ was to set new records that would be recognized worldwide, regardless of politics. And so, the race was on to its next round: time-to-altitude climb. USAF and McDonnell Douglas put on quite a show with a specially modified F-15 – named ‘Streak Eagle’ which broke five world records in one day and eight over two weeks and three days.

Three USAF pilots were designated to reclaim the crown for the U.S. between January 16 and February 1, 1975, over Grand Forks Air Force Base in North Dakota. They took turns in the cockpit of the modified airplane and blasted through previous achievements at supersonic speeds and on full afterburner. The aircraft was essentially a stripped-down preproduction version of the combat airplane.

All unnecessary deadweight was removed – including the paint, 20-mm Vulcan rotary cannon and ammo, radars, radios, and other non-essentials. A pitot boom was fitted to the nose, and high-accuracy instruments were installed for precise speed and acceleration measurements. Thanks to its thrust-to-weight ratio of nearly 1.5:1, the specially-prepped F-15 would set eight records during the 17 days of testing.

On January 16, the five F-4-Phantom II records fell during three attempts made by the F-15. The ‘Time to 3,000 m (9,843 feet)’ was improved by Major Roger Smith by a 20% margin, from 34.52 seconds to 27.57 seconds. A hold-back system was fitted to the Streak Eagle, which then accelerated to full throttle before being released. The short takeoff distance of 400 m (1,220 feet) left very little time for the pilot to retract the landing gear before pulling a 5G vertical climb. Due to this detail, several attempts were aborted as the aircraft neared the never-exceed speed for the landing gear and had to slow down, compromising the trial. However, the pilot eventually got the hang of it and smashed the standing record.

A second flight that same day broke three records, with Major Willard Macfarlane at the stick. ‘Time to 6,000 m, 9,000 m, and 12,000 m’ (19,685 ft, (29,528 ft, and 39,370 ft)’ were simply obliterated by the Streak Eagle’s fast ascend. The old world bests were 48.79 seconds, 61.68 seconds, and 77.14 seconds. The F-15 did it in 39.33 s, 48.86 s, and 59.38s.

In the afternoon, the plane took off one last time for the day, going for the 15,000-meter ceiling (49,212 ft), shaving 37 seconds (or 33%) off the old 114.50 seconds. The twin-engine fighter hit the mark in 77.02 seconds, around 10 seconds quicker than the Saturn V Moon rocket. See the video attached for a detailed and accurate report of the events. Having taken the crown from the aging F-4, the new kid on the block put the Soviet fighter in its sights and floored it. Or, better yet, 'ceiling’ed' it since the next thresholds lay at or beyond 20,000 m overhead. On January 19, Roger Smith aced the ‘Time to 20,000 m (65,617 ft)’ flight, seeing the MiG-25’s 169.80 seconds and raising the Eagle’s 122.94-second performance.

Seven days later, Major Dave Peterson put on the high-pressure suit (all attempts above 15,000 m / 50,000 feet required this special equipment) and dropped below the three-minute mark in the high-speed, high-altitude record. In 1974, the Soviet aircraft hit the required level in 192.60 seconds (three minutes and twelve seconds), while the Eagle managed a 161.02-second performance (two minutes and forty-one seconds).

Finally, on February 1, 1975, the man who first clubbed previous records, Major Roger Smith, got in the cockpit one last time and aimed for the absolute win: ‘Time to 30,000 m (98,425 ft).’ The F-15 outpaced the MiG-25 by over half a minute, scoring 207.80 seconds, compared to the MiG’s 243.86 seconds. Maj. Smith shut down the twin jets after smashing the record to protect the engines from overheating and suffering irreparable damage.

Due to its 2.2-Mach momentum, the Streak Eagle continued on a ballistic trajectory, coasting silently until it hit 103,000 ft (33,792 meters). The extremely thin atmosphere wasn’t absorbing the engines’ heat quickly enough, so the plane – essentially a glider flying at just 55 knots (63 miles per hour, 102 kilometers per hour) – was moving solely on inertia. The pilot pushed over into a 55-degree dive until the plane reached a safe altitude of 55,000 feet (16,764 meters). Major Smith reignited the engines, and the F-15 Streak Eagle safely returned to land at Grand Forks.

The record-setting F-15 was an early version of the standard fighter, 63 feet, 9.0 inches (19.4 meters) long, with a wingspan of 42 feet, 9.7 inches (13 meters), and 18 feet, 5.4 inches (5.6 meters) long. A regular F-15 had an empty weight of 25,870 lbs (11,734 kilograms) and a maximum takeoff weight (MTOW) of 44,497 lbs (20,184 kilograms).

However, the Streak Eagle was 1,800 lbs (817 kg) lighter than a production F-15A. Furthermore, its twin jets were given only the strict amount of fuel necessary to carry the record-breaking attempts. The two Pratt&Whitney afterburning turbofan engines have a Maximum Continuous Power rating of 12,410 lb of thrust (55.2 kilonewtons), a 14,690-lb (65.34 kN) 30-minute limit, and a peak 23,840-lb (106 kN) 5-minute limit. An F-15A Eagle can cruise at 502 knots (578 mph / 930 kph hour), with a top speed of 893 knots (1,028 mph / 1,654 kph) at 10,000 feet (3,048 meters). The supersonic jet can hit 1,434 knots (1,650 mph / 2,656 kph) at 45,000 feet (13,716 meters), and its operational ceiling is 63,050 feet (19,218 meters) at max thrust. The regular F-15s had a thrust-to-weight ratio of 1.15:1, enabling them to climb at 67,250 feet per minute (342 meters per second) from sea level.

The record-setting F-15 Streak Eagle was donated to the National Museum of the U.S. Air Force in 1980 and put on outside display. A coat of camouflage grey paint was sprayed on the historic plane to protect its bare-metal body. The fighter wore the famous livery for over four decades, but it has been recently restored to its correct exposed aluminum finish. It is currently in storage in a hangar at the Museum.
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