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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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Essential Feedback: How Are We Doing?
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Feedback is an essential nutrient to our emotional well-being because humans, as a group, all embody some degree of insecurity. This is especially true in activities where inconsistent variables provide challenges unique to every attempt of an activity. Landing on an aircraft carrier is a good example. Another activity on the spectrum is every post of JetWhine.
Certainly our creative challenges are not as life threatening as those faced by an aviator who’s just called the ball on final to the boat—especially at night in rain roiled seas—but this aviator is one up on us because every trap is evaluated by a critical audience. And in the ready room there are no questions of how those aviators performed because the flight is not over until the evaluators itemize what they did well, what needed improvement, and—supremely important—how they could improve.
Feedback is not a required component of the creative process of publication. And looking at it over the past 30 years or so, it seems to be going the way of paper charts in a pilot’s flight bag. As JetWhine Publisher Rob Mark and I were discussing this reality and brainstorming solutions, I suggested that our best option was also the simplest: Just ask the readers.
So, how are we doing?
Because we all are drowning in media and information, answering such an open-ended question can be daunting. Unsure of where to begin, many of you will likely take time to think about it, until something more pressing and concrete takes its place. So here are some specific questions you can answer by clicking the comment button on this post, or you can share them with a wider audience on JetWhine’s Facebook page.
What story first comes to mind when you think of your favorite JetWhine post, and why was it so meaningful?
And which one did you absolutely detest, and why did you hate it? Did it offer an opinion you disagree with, or did it speak to something in which you have absolutely no interest?
If we missed the concentric circles that define your aviation interests, what are those subjects or topics?
Finally, because we don’t want to consume too much of your time, what is your primary JetWhine access, the blog itself, an email subscription that delivers new stories to your inbox, or the Facebook page?
And because we’re curious, do you share the JetWhine stories that you like or detest with others who don’t subscribe but might agree (or disagree) with your evaluation of our performance?
We appreciate your time and attention in this matter because, like an aviator trapping at night, our desire is to be better on our future attempts. — Scott Spangler, Editor
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Look Ma, No Hands: Aircraft Trim Control
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By Rob Mark
As a kid, telling your mom you planned to try something without holding on was a tipoff something dangerous was surely in the offing.
But when I tell flying students to try letting go of the control wheel or stick at times when I first get to know them, I’m actually trying to help them become better pilots. In this case, it’s all about learning to manage the trim control on the airplane. Pilots who fail to understand the purpose of the trim tab — that little piece of hinged metal on the end of the elevator — or the movable horizontal stabilizer, really are doomed to work way too hard at becoming truly good pilots. I often find that many instructors don’t take enough time to explain the “why” behind trimming an airplane.
Most simply put, trim tabs help maintain an airplane’s state of balance, where all four of those basic forces we learned about as student pilots — power, lift, drag and gravity — come together. Alter any of them and you’ll need to re-trim the aircraft to reestablish that balance.
Failing to reestablish that balance of equilibrium and the pilot is forced to hold back or push forward on the control wheel to maintain altitude or airspeed. While that might not seem like a big deal, it’s one more function of the human brain not available for other important items, like navigating, looking out the window for other airplanes or drones, or keeping an eye on the weather.
The Nuts and Bolts
Here’s an easy trick to bring the trim control into your scan, so to speak. Next time you’re out solo in level flight, simply let go of the control wheel or stick and watch what happens to the nose of the airplane. If the airplane’s properly trimmed, you won’t notice any change at all.
But if the aircraft’s nose drops and the airspeed begins increasing, you’ve been holding the nose up. An opposite reaction means you’ve been holding it down. All of it means you’re working too hard.
Actually, the worst thing you can do right now while you’re not holding the control wheel is to begin fussing with the trim wheel. Trying to fix a balance problem by trim means you’ll simply end up chasing the nose in an endless series of up and down pitch changes. This happens quite a bit when the aircraft is equipped with an electric trim button on the control wheel, because that seems like the quick solution.
The trick though, is to grasp the control wheel and set the nose pitch where you want it first.
THEN trim until you feel no pressure at all. If you’ve done it right, the pitch won’t change when you release the wheel. Still not quite right? Grasp the wheel again and trim just a teensy-weensy bit at a time and let go again.
Want to hold 85 knots in level flight? Set the power and pitch for that speed and trim just a bit nose up or nose down and let go of the wheel. If you did it all correctly, that airplane will cruise along just dandy at 85 knots until one of the forces changes. Same works for a descent. Set the power, drop the flaps and trim until the airplane holds the speed without any pressure on the wheel from you. Climb at 85 and trim off the pressure. It even works in a steep turn if you’re ready for it … turn and trim.
There shouldn’t be any normal configuration on any airplane that doesn’t allow you to trim off the pressure you’re holding. If that doesn’t work, I’d say it times for a visit with the local A&P.
One final tip. If you haven’t yet earned an instrument rating yet, trust me … learning to properly trim the airplane will make your training a whole lot easier. Creating good instrument flying skills will at times, seem to call upon every ounce of your brain power. It all helps save a bit more of that gray matter for the times when you’ll need it most.
Note: This story originally appeared in the February 2015 edition of AOPA’s Turbine Pilot.
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Logging Virtual Flight Time at AirVenture
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One of the most frustrating aspects of getting excited while watching others fly, like the U.S. Navy Blue Angels, is not being able to immediately feed that emotional and physical craving. It figures that technology provided some relief with some virtual flight time in disparate aircraft at the EAA Innovation Center.
Having never before flown a gyroplane or replaced my glasses with virtual reality goggles, I didn’t know what to expect as I reached for the stick, throttle, and rudder pedals (which I slid forward on the floor—ah, legroom at last) of the PAL-V Liberty, a (three-wheel) car that flies and a (gyro) plane that drives.
When Dave started the simulation, which put me on Runway 18 at Wittman Regional Airport (OSH), my first impression was a very real case of spatial disorientation. I can’t remember the last time I had such a strong case of vertigo. I fought through it, following Dave’s instruction to hold the brakes, apply full power, and to hold a neutral stick when I released the brakes.
The steep climb angle—it’s normal, Dave said—only made my vertigo worse. While my eyes and inner ears argued with the seat of my pants, I looked around. Hey, there’s Lake Winnebago, and the four exhibit hangars. Where are all the people? But I must admit it was nice having the place to myself.
Pulling the power to idle abeam the numbers, I started a 180-degree turn to landing. Dave warned me to back off the bank angle a bit. Without any haptic feedback from the controls or the seat of my pants, it was nice to have the aural warning. As usual, I over controlled on final, but I managed to conclude my 2-minute virtual flight by landing to the left of centerline without breaking or bending anything. Removing the goggles, I sat there for a moment to let my eyes, ears, and sit-down parts reach consensus.
At the other end of the Innovation Center aisle was EAA’s powered paraglider simulator. These flying machines have long fascinated me, and I’d watched them fly early that morning, so a virtual flight was the last item on my AirVenture to-do list that needed a tick mark.
After scooting my butt all the way back into the harness, the sim operator pulled the Velcro strap on the throttle on my right hand. A lever like a bicycle hand brake, I’d squeeze it with my fourth and little fingers add power and climb. With my index and middle fingers I’d grab the toggle, which I’d pull to turn in that direction. All four fingers worked the left toggle, and pulling both of them simultaneously was like putting on the brakes.
Unlike all of the pilots who preceded me, I chose the Village Flight, not the Combat Challenge, because shooting at tanks and helicopters and towers would be a distraction. I was going to teach myself how to fly this thing—to climb, cruise, turn, and descend—during my virtual flight time of 90 seconds. The first view of the goggles explained the controls and showed what happened when you pulled the toggles. Cool!
I was just starting to slalom around the trees and buildings when the goggles went dark and the double-barreled fan-supplied slipstream died. But the virtual flight inspired me to seek out training in the real thing, and Google led me to the US Powered Paragliding Association.
Walking back toward Boeing Plaza I passed the Jack Link’s tent. In it, four people were sitting in a tandem-tandem facsimile of a cockpit, each wearing a helmet and virtual reality goggles with mirrored aviator sunglasses stuck on the front. I got in line and had an exiting aerobatic flight with John Klatt in the Jack Link’s sponsored Screamin’ Sasquatch Jet Waco.
The vertigo from my first virtual flight of the day did not return, probably because I was too busy “flying” the maneuvers with him, trying to remember my aerobatic training and where to look to guide the path of each maneuver. Snap rolls were interesting, but not as interesting as the jet powered flat (that’s what it looked like to me) spin. Happy after the multi-minute routine, they treated me to lunch, two samples of Jack Link’s beefsteak protein snacks, which is still jerky to me. — Scott Spangler, Editor