|
The First Few Steps …
… are the toughest, whether it’s learning to walk, ride a bike or, especially flying IFR.
The first few steps of instrument flying may be the most crucial you’ll ever take, but the results are a lot more rewarding. On the other hand, a misstep might cause you far more grief than falling over when you were 12 months old and first learning to walk. Those missteps resulted in a scraped knee, some tears and a cuddle from Mom. A misstep in IFR might well result in a 15 second sound bite on the evening news — the kind that makes non-fliers glad they never left the ground.
What’s so critical about early IFR training? Everything. Your first few IFR lessons establish the foundation of all you’ll do for the rest of your training, for all your time in clouds, for every approach you’ll make. If you learn it right the first time, you’ll be safe.
The first lesson in a typical IFR curriculum usually doesn’t involve hood time. Its purpose is to give you the visual cues of what a 500-feet-per-minute climb looks like on your instrument panel and outside the cockpit. It’s designed to help you get your mind around a standard-rate turn so you’ll know how the instruments are supposed to look, and what it looks like outside. The goal is to let you see how little the mock airplane on the attitude indicator actually moves to establish a 500-feet-per-minute rate of descent.
In that first lesson, you’ll also learn more about trimming an airplane than you ever thought possible. You’ll discover that a perfectly trimmed airplane is your best friend in the clouds — and an improperly trimmed airplane can drive you to distraction. You’ll learn that a power reduction of only 200-330 rpm’s can cause a huge change in the trim required to maintain your altitude and airspeed. You’ll also learn that a perfectly trimmed airplane usually will settle into a 500-foot-per- minute descent fairly easily, and that all you’ll have to do to stop the descent is return the power to its previous setting.
The next few lessons are all about standard operating procedures and flight attitudes — wearing the dreaded foggles or the hated hood. You’ve probably heard the old adage, “Pitch plus power equals performance.” What does it mean? In these lessons, you’ll find out.
What does the instrument panel look like when you establish a “cruise level” configuration? How many RPM’s do you need? What’s the indicated airspeed those RPM’s produce? What should the attitude indicator look like, the vertical speed indicator, the turn coordinator? In a typical general aviation instrument trainer, 2400 rpm’s and a level pitch attitude should result in somewhere between 100 and 115 knots, with the little airplane’s wings exactly on the horizon.
What does approach level mean to you? If you’re trained properly, approach level is the pitch/power combination that produces the basis for all the approaches you’ll fly. If it’s a Cessna Skyhawk, typically you’ve got about 2100 RPM’s to maintain 90 knots indicated airspeed and, perhaps, a quarter of a bar above the horizon line. Now, a quarter of a bar isn’t much and in my early IFR training I couldn’t really tell the difference between a quarter, a half, heck, even a full bar. (Well, maybe a full bar — although my early performance wouldn’t show it.) But as your training time increases, and your experience, you’ll learn that a half bar down could mean a 200-250-feet-per-minute descent.
90 knots is an appropriate approach speed for several reasons. In the real IFR world, there’s probably not a controller alive who will let you shoot an approach at, say, 75 knots, as some people might suggest. 90 knots is fast enough to keep the controllers happy, yet slow enough for you to be able to chop the power, drop the flaps and land the airplane, even if you don’t find the runway until the typical 200 feet AGL decision height and one-half mile visibility that most ILS approaches allow. Another reason for 90 knots is that all the approach charts give you timing figures at 90 knots.
You’ll also be learning about precision and non-precision approach rates of descent. A precision approach is generally flown around 500 feet per minute. On a typical 3 degree glide slope and 90 knot airspeed, your airplane will descend about 472 feet per minute. In a typical Cessna 172, you’d retard the power about 400 RPMs and about a bar-width low on the attitude indicator to reach that rate.
A non-precision approach requires a quicker trip downhill — to a step-down fix, perhaps, or to the minimum descent altitude (MDA). In a 172, you might pull the power back 700 rpms and hold the AI to about a two bar-width deflection to achieve the 700-800 feet per minute that you’d likely need on most non-precision approaches. Heck, there’s a VOR approach in SoCal, the VOR-A to Oceanside Municipal that requires a descent from 2500 feet MSL to the MDA of 1140 feet in less than 3.4 nm. If you don’t descend at 800 feet per minute just after crossing the final approach fix (the OCN VORTAC) you’ll be hard-pressed to get the airplane stable above the MDA in time to look for the runway.
In addition to learning the different power settings for each condition of flight —takeoff climb, cruise climb, cruise level, cruise descent, approach level, precision approach descent and non-precision approach descent — you’ll also learn about the scarier aspects of IFR flight: unusual attitudes and recoveries, stalls and recoveries, and steep turns. All of this training is geared to get you to the point that flying the airplane in its various configurations and conditions becomes second nature to you. You see, flying an instrument approach in actual conditions requires a level of concentration, a focus, a commitment, that few people ever achieve. A former colleague of mine, a man with more IFR experience than I’ll ever see in my lifetime, used to tell a story about IFR approaches:
“Most people want to get involved in instrument flying, but they don’t understand that an instrument pilot flying an instrument approach requires a commitment,” he would say. “Do you know the difference between involved and committed?” he’d ask. The response usually was a shrug. “Well, he’d say, 'Think about the last time you had a ham and egg breakfast. In a ham and egg breakfast, the chicken was involved … but the pig was committed.' ” After a chuckle, he’d say, “And in order to be a successful instrument pilot flying flawless instrument approaches, you’d better be committed … or it’ll be you that’s had his last breakfast.”
Instrument training isn’t difficult. But it requires a commitment of time, energy and focus. While your early instrument training may seem repetitive, or even boring, it’s critical that you learn early on how to control your airplane, instinctively, for each flight regime required. Your approaches will be safer, your flying investment will seem more worthwhile and your confidence level will soar when you complete the training.
Just remember that those first few steps sometime require a scraped knee or two before you get the picture. Once you do, you’ll be thrilled indeed that you spent all that time learning to do it right, from the beginning.
About the author:
Glenn Daly is the chief pilot of SoCal Skies in San Diego and is in love with flying and teaching others to fly.
© 2003-2005 by Stephen Glenn Daly
|
Aviation Training