Practical application of scenario-based training
Scenario means "an outline or model of an expected or supposed sequence of events." Most of our flight training, even if we teach to the Practical Test Standards, is scenario-based. When you began training with a primary student, a great deal of time is in the practice area making power and attitude changes. A typical training scenario may sound like this: "Once we get to our cruise altitude, I'd like to configure the airplane for 100 knots indicated." The student answers, "OK." After your student achieves 100 knots and trims the airplane, you say, "Now let's go 80 knots and make a descent at 500 feet per minute." The student then adjusts the power and re-trims the airplane for a descent at 80 kt. You then say, "Hey, I have an idea! Let's add one notch of flaps and see what happens."
Are you beginning to see what is happening? The next step is full flaps and slow flight, precisely like landing an airplane. Just another day in the practice area, except lower. I can't think of a better outline or model of an expected or supposed sequence of events.
Here are some other common tools that can be used in a scenario setting to help you teach proficiency in landings:
Hands-off trim. One key to a good landing is having the airplane in a stable condition. Many students have likely heard about flying the airplane "hands off," but you may need to help them understand that "hands-off flying" simply means having the airplane properly trimmed, not using the trim control to fly the airplane. An airplane trimmed for 105 kt in cruise is obviously different than one trimmed for an 80-kt descent in the pattern.
Dynamic stability. Most of our training aircraft are dynamically stable, meaning the aircraft will return to its original condition after being disturbed. To prove the point about dynamic stability to your student, try the following exercise in the practice area. In level flight, trim the aircraft for a speed 20 knots below maneuvering speed (VA). Once the aircraft is set up and you've cleared for other traffic, rotate the aircraft about its lateral axis by pulling back on the yoke. Let go and watch what happens. Unless your trainer is a Geebee, you will see the airspeed and altitude oscillate until the airplane returns to the original attitude and airspeed. Why? Because the airplane is trimmed for a specific configuration and it has positive dynamic stability.
For the next test, leave the aircraft trimmed, but reduce the power setting by 300 rpm, then put your hands back in your lap. What happens? The airplane descends. Oh, sure, it oscillates for a while, but being the stable little trainer that it is, it will eventually settle down to the original airspeed in a nice stable descent.
Airspeed stability. Get your flying machine back up to altitude, in level flight and trimmed for 20 kt below VA. Now give the airplane a good dose of nose-up trim. What happens? The airplane noses up, loses some airspeed, then oscillates, but eventually it settles on a new airspeed, and if the engine has enough power to overcome the additional drag at the new configuration, the aircraft should be in level--but slower--flight.
How do we turn dynamic stability into good landings? Show the student that power and pitch adjustments will translate into good landings. One way is to introduce the yoke as the "attitude adjustment device," used throughout the landing process to make pitch adjustments. The trim is there to take pressure off the yoke after such an adjustment. After applying trim, the aircraft will either be at a new attitude (climbing, descending, or level) or at a new airspeed.
Once the student has a better understanding of trim and dynamic stability, it should be simple for him or her to get the airplane configured for the landing. Have your student enter the downwind leg at slow cruise, slow the airplane to 20 knots below VA on downwind, and configure the nose (yoke) and trim to descend at 500 fpm. Have him add a notch of flaps abeam the numbers (make sure you are within the flap operating range) and remind him to use the yoke to keep the nose from rising when he adds the flaps.
At a point 45 degrees from the approach end, have him add the second notch of flaps and keep the nose down in the turn to base, and re-trim for the new airspeed. A nice shallow turn to final should line him up with the centerline of the runway.
The airplane should be set up on final about 400 feet agl, and after he adds the final flaps, the airspeed should settle on the predetermined final approach speed. The final flap setting will still cause the nose to rise, of course, so be sure to remind the student to keep the yoke pressure forward and re-trim for the final approach speed.
Out the window, the landing spot picked while on downwind should be staring right at you, not moving. If it is moving, the airplane will either land in front of it or behind it. So have the student make adjustments as necessary to keep the spot in the same place in the windshield. This is where it helps to apply the lessons learned in the practice area about using power adjustments to control the descent rate and pushing or pulling on the yoke to make the airspeed fluctuate. Have your student do what it takes to hold the airspeed (yoke) at the final approach speed and make small power adjustments to let the airplane come back to Earth (unless, of course, a big power adjustment is needed). It won't take too long for the student to realize that this is the same flying he's been doing in the practice area.
After a stabilized approach comes the part of the landing with which many students have difficulty: the flare. Have your student just keep flying the airplane all the way to the ground. The flare is really nothing more than arresting the sink or descent rate of the aircraft once close to the ground by using the yoke to keep the nose off of the ground. When the airplane is on a stabilized approach and is just a few feet off of the ground, have your student adjust the flight attitude to level flight so the airspeed bleeds off while the rate of descent moves toward zero.
As the airplane gets closer to the ground, direct the student to keep the airplane from touching down by increasing back pressure, ever so slightly. With back elevator pressure applied and no power, the airspeed will continue to bleed off. Soon enough the airplane will stop flying and the main gear will touch down on the runway.
At this point, many students mistakenly believe the landing is over and give up; they may let go of the yoke or throttle. Remember, the airplane has to come to a full stop. Remind your student to always keep both hands active on the yoke and throttle until the landing is over.
After a few successful landings, your student will realize that landing an airplane is nothing more than flying the airplane. Pitch, power, trim, airspeed--just like in the practice area.
Laurence J. Sentiff is a CFII who flies for Lifestar Inc. as a volunteer pilot. He has been flying since 1995 and instructing since 2001.
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