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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.
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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A Cockpit Crawl into Naval Aviation History
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Am I the only aviator who wants the pilot’s perspective when examining an interesting aircraft? Or am I suffering from unrequired Walter Mitty daydreams? Either way, with a cockpit crawl of more than a dozen aircraft, from the F11F Tiger to the F-14 Tomcat, the National Museum of Naval Aviation is a hangar of dreams in Pensacola, Florida.
Scattered throughout the museum are more than a dozen cockpit procedure trainers (CPTs), which are exactly like fleet aircraft with their wings and most of their fuselages amputated. Each of them taught naval aviators where to find the necessary system information, and what to look for before they made their initial flights in these (mostly) single-seat aircraft.
Climbing into the F-8 CPT during my first visit to the museum in 1972 is a lasting memory because I fit! But I was 5 inches shorter then, so looking to try it (and any others) on was a premeditated goal of this 21st century visit. Seeing the F11F Tiger (above) and the F-4 Phantom CPTs, both in their Blue Angel uniforms, gave me hope that was not disappointed. It has new paint, but I still fit. (Let the day dreams continue!)
While there isn’t any power or instrument life in the CPTs, and the canopies don’t close, but the sticks and rudder pedals (and rudder pedal adjustment cranks) still move from stop to stop. They range from the F11F and T-28, which entered service in the 1950s, to the F-14 Tomcat, which retired from active fleet service in 2006.
Making a cockpit crawl in chronological order is not only a first-hand look at the development of the technology they employ but also the advancement in what test pilots call the “pilot-aircraft interface.” The need for naval aviators to be contortionists clearly diminished over the years.
And then there are anthropometrics, the maximum and minimum measurements that play a large role in which pipeline—jets, helos, or multiengine—is open to a prospective naval aviator. It’s more than just standing and sitting height or buttocks to knee length. They measure every aspect of a prospective aviator’s functional reach, and your arms can be too long (as I found out when trying to reach the switches in the back corners of the Tiger’s cockpit) as well as too short.
The helo cockpits have the most room, with the HH-52 (essentially a single-engine SH-3 Sea King) having much more than the AH-1 Sea Cobra. Subjectively, among the jets, those made by Chance-Vought (the F-8 Crusader and A-7 Corsair II) and Grumman (the F11f and F-14), offered more leg room than those made by McDonnell (the F-4 Phantom) and Lockheed (the S-3 Viking).
The lines of children and adults waiting for the AV-8A Harrier and T-2 Buckeye were a bit longer, and with so much more to see, I didn’t make the time to try them on. Maybe next time. — Scott Spangler, Editor
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An Introductory Flight of Frustration
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Following Santa’s directions, for Christmas my oldest son’s wife got him an introductory flight lesson. I can’t remember any gift in the preceding years that left him so excited. An ICU nurse living in the metropolitan Kansas City, it took awhile for the weather to align with his work and family schedules (that happens when you have four kids). But he was patient, and his eager anticipation never dimmed, until he actually made the flight.
On his way home from the airport he called in a state of agitated consternation. To summarize our hour long conversation, the intro lesson was much less than he anticipated, and he pelted me with a series of questions whose common denominator was, “Was I expecting too much?” As he stepped through the lesson, if you could call it that, the answer to each question was no. What Santa brought you was not an introductory flight lesson but an hour of flight time for a safety pilot posing as a CFI.
My son described him as a “professor,” of what he didn’t know or say. He was “older than me, but not as old as you, Pops,” which put him somewhere between 31 and 64. And there was very little conversation before the flight. He didn’t ask why my son wanted to become a pilot and how he hoped to use this precious, hard-earned skill once he’d earned the certificate. Nor was there any preflight discussion of what they would do during the lesson. “He checked the oil and said, “Let’s go flying.’” said my son.