Better pilot: Are you ready to land?

It takes practice, patience, and persistence. But once we master the skill, it pays handsome dividends every time we fly. It's true that every landing is different, but ...
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Are You Ready to Land? Flying the stabilized approach Robert N. Rossier

I

t was my first solo, and by all measures, everything was going well. But on short final I suddenly found myself way over my head. Poised on the runway ahead was an airplane pointed right at me. This was not a situation I’d ever encountered in my brief tenure as a student

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of flight. To be completely honest— it caught me by surprise. More importantly, it distracted me. With that distraction the nose dropped, the speed increased, and I made a stark deviation from what the approach was supposed to look like. Before I decided to go around I

saw that the aircraft was scooting off the runway; in mere seconds the runway would be clear. Unfortunately, it was too late for a good approach. I missed the trees on the runway’s approach end, but the landing was far from “made.” I bounced—a couple of times and

badly—but I finally advanced the throttle to end the misery of my botched attempt and begin anew. That was years ago, but the problem of poor landings is one that continues to plague many pilots. There’s nothing that makes us feel better, or look better, than a good landing. More importantly, a good landing—one that puts our main tires on the pavement at the right place, speed, and attitude—is a safe landing. But there’s much more to making a good landing

A stabilized approach is where the aircraft is properly configured and maintains a constant airspeed and descent rate on a constant vertical flight path to the touchdown zone. than flaring at the right time. A good landing starts as we make our approach to the runway. This is where we configure the aircraft, set our speed, and initiate a descent that brings us to the touchdown zone ready to make that smooth flare. All too often, unseen factors complicate the approach, and we fail to arrive at the right place and time. In essence, we’re just not ready to land. Many factors can affect our readiness to land, such as my distraction with the runway surprise. Maybe we’re rushed because the tower has told us there’s a jet on our tail, or we’re anxious to get safely on the ground because of impending weather. Maybe it’s a simple case of “get-there-itis.” Or maybe it’s poor planning—not getting things done when they need to be done, and then rushing at the end to get it all done. Then there’s the problem of plain old sloppiness— EAA Sport Aviation

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better pilot not flying the approach the way we’ve been taught. Whatever the cause, one part of the cure is to always fly a stabilized approach.

The Stabilized Approach A stabilized approach is where the aircraft is properly configured and maintains a constant airspeed and descent rate on a constant vertical flight path to the touchdown zone. This means we’ve done all that needs to be done, like slow the airplane down, put down the gear, adjust the mixture, apply carburetor heat, or anything else necessary for the particular aircraft. It means we’ve completed the before-landing checklist, we’ve performed any passenger or approach briefings, and that we’re truly ready to land. Generally, an approach is considered stabilized when the following criteria are met: 1. The aircraft is on the correct

DV D E N T E R T A I N M E N T

flight path. 2. Only small pitch and heading changes are required to maintain the correct flight path. 3. The aircraft is flying at the recommended approach speed (adjusted for wind gusts). 4. The aircraft is in the landing configuration. 5. The sink rate is no greater than 1,000 fpm. (If an approach to a particular runway requires a sink rate greater than 1,000 fpm, conduct a special briefing.) 6. The power setting is appropriate for the aircraft configuration. 7. All briefings and checklists have been completed. The general guidelines offered by the FAA, and followed by most professional flight departments, require pilots to achieve a stabilized approach at a point no lower than 1,000 feet above ground level (AGL) for an instrument approach, or 500

feet AGL for a visual flight rules (VFR) approach. Any time we find we’re not stabilized when we should be, there’s only one thing to do—go around. According to the FAA, the underlying philosophy is that a stabilized approach allows pilots to “determine displacements from the course or glidepath centerline, to mentally project the aircraft’s threedimensional flight path, and then to apply the control inputs necessary to achieve and maintain the desired approach path.” In other words, a stabilized approach makes it easier for us to see the effects of wind shear and other factors that can foul us up during an approach. If we aren’t flying a specific airspeed or using a known power setting, then we may not recognize the effects of a tail wind, or realize when we’ve suddenly encountered wind shear. If we

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aren’t flying a constant flight path to the touchdown zone, then it’s really hard to tell if we’ve suddenly gone above or below the right glidepath. When flying a stabilized approach, we can often recognize a problem before we encounter it. Just such a situation arose one day when I was landing at Jeffco Airport in Broomfield, Colorado. A 20-knot wind was blowing right down Runway 11, but my power setting, airspeed, and approach path told a different story. The throttle was near idle, rather than above normal as it should be for a head wind. My airspeed was dead on, but my glidepath said I had a tail wind. I prepared for what I now knew was to come. Sure enough, just 30 feet above the pavement, the wind suddenly sheared from a tail wind to a head wind. Had I not been paying attention to my stabilized approach criteria, I might have been taken by surprise, and the result would have been sloppy at best. Besides making telling details clear, flying a stabilized approach reduces our final approach workload and allows us to divide our attention adequately enough to take in other important details, like the airplane that just entered the runway, the geese poised for takeoff from the grass near the runway’s end, or that airplane making a practice instrument approach to the opposite runway. Destabilizing Situations Many factors can destabilize our approach, like maneuvering to avoid hazards or aligning the aircraft with the runway. Another is any steep turn—especially one that becomes uncoordinated. What many pilots fail to consider is the relationship between approach speed, bank angle, load factor, and stall speed. For example, the approach speed of many general aviation airplanes is 1.3 VSO (the stall speed in the landing configuration). It provides a EAA Sport Aviation

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better pilot sufficient safety margin, as long as we don’t get carried away maneuvering. But what happens when we suddenly make a steep turn to avoid a collision or other unexpected situations? In a level turn, the stall speed increases dramatically when we exceed moderate bank angles. At shallow bank angles—say up to 20 degrees or so—the increased load factor and resultant increase in stall speed in a level turn are fairly insignificant. Roll that bank up to 40 degrees in a level turn, and we suddenly increase the stall speed by 14 percent. Increase the bank angle to about 55 degrees, and we’re right at 1.3 VSO—right on the verge of an accelerated stall (see Table 1). Sloppy flying and letting our airspeed drift below the recommended approach speed compounds the risk. For an aircraft with a 50-knot stall speed, a 10-knot error is 20 percent, and could result in a stall at less than 40 degrees of bank. Make

Table 1—Load and Stall Speed Factors in Level Flight Bank Angle 0 20 40 60 80

Load Factor (g’s) 1.00 1.06 1.30 2.00 5.76

Sloppy flying and letting our airspeed drift below the recommended approach speed compounds the risk. an abrupt steep turn to avoid birds, aircraft, or other hazards, and you could end up nose first in the dirt. As experienced pilots, it’s easy to think that we’re less likely to fall victim to such a situation. However, according to a recent study by the Air Safety Foundation, pilots with commercial certificates are more likely to

Stall Speed Factor 1.00 1.03 1.14 1.40 2.40

fall victim to stall-spin accidents than private or student pilots. And once we’re in such trouble, there may be no way out. The chances of recovering from or surviving a stall-spin at pattern altitude are not good. Flying a stabilized approach isn’t always easy. It takes practice, patience, and persistence. But once we master the skill, it pays handsome dividends every time we fly. It’s true that every landing is different, but if we fly a stabilized approach, we minimize the variables and greatly improve our chances for making a safe, smooth landing.

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