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Making the Brazilian ATR-72 Spin
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Note: This story was corrected on August 10th at 10:23 am, thanks to the help of a sharp-eyed reader.
Making an ATR-72 Spin
I wasn’t in Brazil on Friday afternoon, but I saw the post on Twitter or X (or whatever you call it) showing a Brazil ATR-72, Voepass Airlines flight 2283, rotating in a spin as it plunged to the ground near Sao Paulo from its 17,000-foot cruising altitude. All 61 people aboard perished in the ensuing crash and fire. A timeline from FlightRadar 24 indicates that the fall only lasted about a minute, so the aircraft was clearly out of control. Industry research shows Loss of Control in Flight (LOCI) continues to be responsible for more fatalities worldwide than any other kind of aircraft accident.
The big question is why the crew lost control of this airplane. The ADS-B data from FlightRadar 24 does offer a couple of possible clues. The ATR’s speed declined during the descent rather than increased, which means the aircraft’s wing was probably stalled. The ATR’s airfoil had exceeded its critical angle of attack and lacked sufficient lift to remain airborne. Add to this the rotation observed, and the only answer is a spin.
Can a Large Airplane Spin?
The simple answer is yes. If you induce rotation to almost any aircraft while the wing is stalled, it can spin, even an aircraft as large as the ATR-72. By the way, the largest of the ATR models, the 600, weighs nearly 51,000 pounds.
Of course, investigators will ask why the ATR’s wing was stalled. It could have been related to a failed engine or ice on the wings or tailplane. (more…)
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How the FAA Let Remote Tower Technology Slip Right Through Its Fingers
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In June 2023, the FAA published a 167-page document outlining the agency’s desire to replace dozens of 40-year-old airport control towers with new environmentally friendly brick-and-mortar structures. These towers are, of course, where hundreds of air traffic controllers ply their trade … ensuring the aircraft within their local airspace are safely separated from each other during landing and takeoff.
The FAA’s report was part of President Biden’s Infrastructure Investment and Jobs Act enacted on November 15, 2021. That bill set aside a whopping $25 billion spread across five years to cover the cost of replacing those aging towers. The agency said it considered a number of alternatives about how to spend that $5 billion each year, rather than on brick and mortar buildings.
One alternative addressed only briefly before rejecting it was a relatively new concept called a Remote Tower, originally created by Saab in Europe in partnership with the Virginia-based VSATSLab Inc. The European technology giant has been successfully running Remote Towers in place of the traditional buildings in Europe for almost 10 years. One of Saab’s more well-known Remote Tower sites is at London City Airport. London also plans to create a virtual backup ATC facility at London Heathrow, the busiest airport in Europe.
A remote tower and its associated technology replace the traditional 60-70 foot glass domed control tower building you might see at your local airport, but it doesn’t eliminate any human air traffic controllers or their roles in keeping aircraft separated.
Max Trescott photo Inside a Remote Tower Operation
In place of a normal control tower building, the airport erects a small steel tower or even an 8-inch diameter pole perhaps 20-40 feet high, similar to a radio or cell phone tower. Dozens of high-definition cameras are attached to the new Remote Tower’s structure, each aimed at an arrival or departure path, as well as various ramps around the airport.
Using HD cameras, controllers can zoom in on any given point within the camera’s range, say an aircraft on final approach. The only way to accomplish that in a control tower today is if the controller picks up a pair of binoculars. The HD cameras also offer infrared capabilities to allow for better-than-human visuals, especially during bad weather or at night.
The next step in constructing a remote tower is locating the control room where the video feeds will terminate. Instead of the round glass room perched atop a standard control tower, imagine a semi-circular room located at ground level. Inside that room, the walls are lined with 14, 55-inch high-definition video screens hung next to each other with the wider portion of the screen running top to bottom.
After connecting the video feeds, the compression technology manages to consolidate 360 degrees of viewing area into a 220-degree spread across the video screens. That creates essentially the same view of the entire airport that a controller would normally see out the windows of the tower cab without the need to move their head more than 220 degrees. Another Remote Tower benefit is that each aircraft within visual range can be tagged with that aircraft’s tail number, just as it might if the controller were looking at a radar screen. (more…)
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87 Steps to the Moon
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Journey to Mission Control Enriches Memories of Apollo 11
A half century ago, I was one of the millions worldwide who watched Neil Armstrong and Buzz Aldrin bounce and bound across the surface of the moon. But I didn’t fully appreciate their accomplishment until July 10, 2019, 10 days after NASA and the National Park Service dedicated Apollo Mission Control, refurbished to its 1969 lunar landing configuration, as a National Historic Landmark, and 10 days before the 50th anniversary of the fulfillment of the team’s goal.
This journey back to 1969 started at Space Center Houston, the civilian portal to the Johnson Space Center campus. More than a hundred of us climbed into the open-air tram for the flight through Houston’s humid heat to Building 30N, the Christopher C. Kraft, Jr. Mission Control Center . On the way, our guide, Jerry, pointed out the home for the Orion program and the Astronaut Training Center, available for tours with separate tram rides.
Closely clustered in 30N’s lobby, Jerry itemized a rather lengthy list of rules, and mentioned more than once, that we would need to climb 87 stairs to the restored mission control. There’s an elevator, he said, but it, too, is original, with room for six 1960-sized humans, “and it is slow.” Cell phones didn’t exist then, either, he said, so turn them off or silence them now. And keep them in your pockets or bags, he said, reemphasizing his repeated warning that we could take no photos or make any video or audio recordings until the presentation was over.
And we should not lean on the counters in the viewing area and, please, to move to the end of the row to theater-like seats in the observation area. It, too, is in its 1969 configuration, right down to the small ashtrays on the back of every other seat. Most of the visitors had no idea what they were for, and many opened the lid and probed the recess with their skinniest finger. Apparently, the restoration was not total because no one I saw found a 50-year-old cigarette butt. Finally, we must be quiet as we climbed those 87 stairs because they passed an active second-floor mission control room, and we must not disturb them.
The presentation played on the two 19-inch CRT TVs mounted at the intersection of the ceiling, outside walls, and full-width window that separated the spectator seating from mission control proper. There were color TVs, and I wonder if the originals were black and white sets. The narrator was Gene Krantz, the flight director who told the Apollo 13 mission control team that “failure is not an option.” And on this journey, I learned that he was the flight director for the Eagle’s lunar descent leg.
Ghosts who lived on the other side of the glass did most of the presentation’s talking through original audio recordings. Krantz introduced every phase of the flight, each one illustrated by different images on the big screens that spanned the front wall of mission control. On the rows of consoles that faced them, indicator lights danced and twinkled like some holiday celebration and smaller screens displayed another array of data unreadable from our seats.
The presentation was a déjà vu situation for me; not from a half-century ago (for the commercial TV networks never broadcast the “boring” mission control environment), but from the night before, when I watched the Apollo 11 documentary produced by CNN Films. This opportunity was serendipity. Visiting family who live in Houston, they were showing my wife and me how they cut their cable TV coax with online apps, and Apollo 11 led the list of new content on YouTube TV. (The content was so similar, I wonder if they edited the film into the shorter presentation, and added Gene Krantz.)
If you haven’t yet seen this film, don’t miss it. It reveals previously unknown (at least to me) aspects and insights to the mission that for too many of us is summarized by the lackluster video of Armstrong taking his first step off the LM. Buzz Aldrin gives us a crisper, better view of this step from his perch in the Eagle. This and other footage, not seen since it was shot a few days short of a half-century ago, separates this film from all the rest. And this, too, was serendipity, when the filmmakers found 160 reels of large format 70-mm film and more than 11,000 hours of uncatalogued original audio in the National Archives.
And then the filmmakers digitally scanned and enhanced this large format film to 4K, 8K, and 12K resolutions. At this level of detail, when you stare into the unblinking eyes and set faces of Armstrong, Aldrin, and Collins as they suit up, you can viscerally feel their focused apprehensive anxiety. They know that this could likely be a one-way trip. You can see it in each of their faces. In a 2013 TV interview, replayed during this week’s Apollo mania, Buzz Aldrin said they gave themselves a 60 percent chance for success.
The trio presented much happier faces from their Airstream isolation on the USS Hornet (CV-12) which plucked them out of the Pacific. Some years ago, I saw an interesting display of this recovery, and that of Apollo 12, in the hangar bay of the Hornet, now a museum floating in San Francisco Bay. At the now-closed NAS Alameda, you’ll find it moored at the same pier where its predecessor, the USS Hornet (CV-8) loaded the Tokyo-raiding B-25s. It seems a safe bet that the faces of those 80 men might have mirrored those of the Apollo 11 crew.
One of history’s many and ongoing rewards is how it transcends time, connecting past and present, as those who pursue it reveal new information that gives it new life and deeper meaning and context—and fuller appreciation. A half-century ago, my impression of our inaugural arrival on the moon focused on three men. Now, it encompasses the hundreds of humans who climbed those same 87 steps every day to make that arrival possible. — Scott Spangler, Editor
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Flyboys World War II Perry Flag Flight
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One of history’s many rewards is discovering little known stories that enrich the significance of its mass market events, such as the surrender ceremony aboard the USS Missouri (BB-63) in Tokyo Bay in September 1945. There are a number of them, including the saga of the Perry flag, awaiting the curious in Flyboys: A True Story of Courage by James Bradley, author of Flags of Our Fathers.
The book’s core is about the fate of the flyboys, naval aviators, including George H.W. Bush, who attacked the Japanese radio station on Chichi Jima. Situated between between Japan and Iwo Jima, it was the communication link that would warn of approaching flights of B-29s from islands to the south.
Looking at the photo, you’ve likely guessed that shows General Douglas MacArthur at the surrender ceremony on the Missouri. If you look closer at the framed flag in the background, you’ll count 31 stars on it. The Perry flag, Bradley explains on page 303, is the linen US flag that Commodore Mathew Perry carried ashore when he stepped ashore in Japan in 1853. (Equally interesting, the Missouri was anchored in approximately the same position as Perry’s flotilla). But that’s not the really interesting part.
Until just before the surrender, the Perry flag was on display at a museum at the U.S. Naval Academy in Annapolis, Maryland. Someone thought its display at the surrender was significant enough to entrust it to a courier, Lt. John Bremyer. Starting from Annapolis, he took off from Iwo Jima on August 29, 1945, “the last leg of a record-breaking120-hour, 9,500-mile-long trip that had taken him through 12 time zones.”
Led astray by the record-breaking aspect of his trip, I expected to find some description of a flight on par with the Truculent Turtle, the Lockheed P2v Neptune that flew nonstop from Perth, Australia, to Columbus, Ohio—11,235 miles—in September 1946. Finding no joy, I went after Lt. Bremyer. There are a number of them, and the obituary of John K. Bremyer, a lawyer who died, at age 88, on April 17, 2008 in McPherson, Kansas, where he was born on April 5, 1920, mentioned that he’d carried Perry’s flag back to Japan.
But there was no mention of a dedicated flight. Surely there must have been one because, Bradley wrote, Bremyer completed his mission when he handed the boxed flag to Admiral Halsey on the Missouri. “Then the weary lieutenant slept for two days.” The tantalizing details eluded me, and I couldn’t quit searching for them. Then I found Bremyer’s oral history at the Nimitz Education & Research Center at the National Museum of the Pacific War.
It turns out that there was no dedicated flight, which was slightly disappointing. On the other hand, I learned about a Priority One (or One Priority) World War II military travel voucher, which guaranteed a seat on the next airplane, regardless of type or what passenger got bumped, going in the right direction. When he reported to work that morning, he didn’t expect the assignment.
Bremyer was in the air that evening, headed to San Francisco. From there he took the next plane to Hawaii, then Johnston Island, Kwajalein, Guam, and then Iwo Jima. There “they were going to to put me on a destroyer, but that would take too long, so I got on a Black Cat PBY” that took him to Tokyo Bay, where a whaleboat from the Missouri collected him and Perry’s flag.
Watching the proceedings from the above the main deck, Bremyer carried the flag, as well as news releases, photographs, and motion picture film of the surrender back to Washington. “I got on a PBM [Martin Mariner seaplane] back to Guam and basically followed the same route back to San Francisco,” the 85-year-old veteran remembered.
Perry’s flag is back on display at the Naval Academy Museum, and it is No. 89 in “A History of the Navy in 100 Objects.” It gives more background on the decision-making process that sent the flag to Japan, and it mentions Lt. Bremyer’s “record-setting” trip. But like Bradley in Flyboys, it doesn’t explain what record Bremyer’s trip set or surpassed. — Scott Spangler, Editor.
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Gliders Launch with 454 Cubic Inches of Pull
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Gliders—sailplanes—are engineless flying machines powered by gravity’s conversion of altitude into airspeed. Without a doubt, they are aviation’s purest expression of flying for fun. It is also the most social aeronautical neighborhood, because glider pilots alone cannot pull their craft aloft for a flight’s initial investment of altitude.
I discovered Sky Soaring Glider Club last year, when its Cessna 150 tow plane, with its more robust powerplant, swooped low on its touchdown pass to the club’s 3,000-foot turf strip that is perpendicular to U.S. Highway 20 in Hampshire, Illinois. Imitating an owl’s cranial rotation as we passed, I saw a gaggle of waiting gliders and a covey of humans scurrying around them. With an appointment to keep, I promised that I would return.
Because they fly for fun, I figured that the club members would be making the most of a balmy, sunny Saturday. We finally had one of those last weekend. Which was why I was worried by the silence when I rolled into the gravel parking lot. Two men were readying a Schweizer 2-33, but there was no internal combustion buzz. One of the men held the two-place glider’s wing level and, without a word, it leaped forward. After a step or two, he let go.
Around the corner of hangar, sitting under an umbrella covered picnic table, the launch director listened to the glider’s pilot calling out the airspeed and altitude. The speed was a constant 60 mph. The altitude rapidly increased to 2,000 feet above the ground, when he let go of the tow rope that has pulled him aloft.
After the launch director called ATC to file a pilot report of the glider’s release altitude, he explained it’s hard to see the quarter-inch tow rope, and hitting it would not be good. Absent a tow plane, the only launch alternative was a winch, but where was it? Pointing down the runway to the east, “a mile that way.”
As I was getting my steps in for the day, a brightly stickered Honda Accord with an unusual red roof rack was slowly driving in the opposite direction, dragging two brightly colored cords, one red, one yellow. This must be the “mule” the picnic table guys were talking about. Coming to the end of the turf strip, a half-mile into the adjoining farmers field was the orange snout of the winch, with a flashing yellow light on top of its cockpit cage.
“Normally we winch from the end of the strip,” said winch driver Don Grillo, “but the farmer hasn’t been able to get his crops in because of the weather, and he let us add another 2,000 feet.” A winch’s launch ratio is roughly 3:1, so the mile-long tow rope would get the Schweizer to 2,000 feet.
With the winch at the end of the turf strip instead of out in the farmer’s field, it will pull the 2-33, with its under nose tow hook, to 1,000 feet. The higher performance PZL Krosno KR-03, Puchatek glider pulls a bit higher because the towline attached under its CG, allowing a more acute climb angle. After either glider lets go of the two rope, a ribbon drag chute prevents its freefalling tangle.
As the mule pulled the tow ropes back for the next launches, Don explained the winch the club built on the frame of a used box truck. The two-drum Tost winch is from Germany, it’s powered by a “GMC 454-cubic-inch crate engine—same as a Corvette—with the Turbo 400 transmission locked in second gear.” Next to the tachometer is an instrument panel switch labeled N and D. On the cockpit’s right sidewall is the throttle, and left and right levers either engage each towrope to the transmission or apply the brakes to its rotation.
Don is one of the club’s four winch drivers, and all three members of the launch crew, which includes the launch director and mule driver, are club certified after successful completion of the training program. “I started driving the winch last year,” said Don. “It’s exhilarating, a lot of fun, but it’s a critical job. You have to pay attention to the glider, which you can’t see at first. You have to talk to the launch director on the radio.”
Getting ready for the next launch, Don dons his David Clark headset. Even with its muffler, the 454 running at 4,500 rpm in second gear is pretty loud. He’s also listening to the launch director and the pilot, who’s calling out the glider’s airspeed. Pull too hard and you’ll overstress the glider. To prevent that, there are several stress-calibrated break links in the towline by the drag chutes.
With the winch’s singing silenced by the engine’s effort, the Krosno rises above the horizon, climbs steeply, and disappears. When it releases, the rpm jumps suddenly. Don adjusts the throttle to maintain an even strain on the drag chute. As John Abramski connects the towropes to the mule for the next launches, Don tells me that this launch set a new club record for the Krosno of 3,100 feet AGL. — Scott Spangler, Editor