"You throttle-jockeys think you know it all. But I'm here to tell ya you're not ready. This seat of the pants stuff you've been used to just won't cut it over Europe. Before we put you in a B-17 for real, you've got to know that when you get into the soup, you can use, and trust, your instruments."

From the back row, the smart-aleck of the squadron (think Ronald Reagan, grinning that grin) pipes up:

"...Aw, that's all a bunch of baloney!"

...At which point you channel-surf over to the World's Strongest Man re-run on ESPN2, confident that cadet Reagan will learn his lesson by the end of the picture, even if fellow cadet Robert Montgomery ends up with the girl.

Major Tracy wasn't kidding about the instruments, though. Anytime you enter instrument conditions, defined as not being able to use the horizon as an attitude reference, it's vital that you know how to fly on instruments.

It often surprises non-pilots, but when you can't see the horizon you can't tell whether you're wings level, banked, climbing, or diving. In fact, I could strap you in the back seat of a two-seater, blindfold you, and, maintaining a steady one 'g' acceleration, slowly turn you completely upside down without you even realizing it. You'd swear we were still flying straight and level. I can remember countless times in my navy pilot days when, flying through clouds, I'd have vertigo so bad my inner ear made me certain I was banked 90 degrees, though my attitude gyro showed I was level.

This phenomena cost many, many lives, and continues to do so - see, for example, JFK Jr. A pilot thinks he or she is safely straight and level when they're actually in a spiral death dive.

Instrument technology started to catch up with this problem in about the 1930s, pioneered by the Sperry corporation, among others, (and famously tested by Jimmy Doolittle, who flew a complete flight in an opaquely sealed cockpit.) But instrument flying is a skill that requires a lot of continuous practice.

Nowadays, both civilian and military flight instruction in instrument flying involves both simulators and actual flight under a hood. In my experience, this took the form of an instructor in the front seat and me in the back seat of the 2-seat trainers then in use (the T-28 Trojan, the T-2 Buckeye, and the TA-4J Skyhawk) with the instrument flying hood, a canvas cover on an extensible framework, pulled forward so that it completely obscured all vision from the back seat of the outside world.

In this configuration the student would fly the entire hop, from the initial takeoff roll down the runway to the last half-mile or so before touchdown. All on instruments.

So, how do you do it? As it happens, you can learn a surprising amount with nothing more than your common and garden PC and one of the various PC flight simulator programs now available. In this writeup, I propose to describe how you can practice some of the basic instrument flying training maneuvers employed in both civilian and military flight instruction.

<obligatory disclaimer>

None of the material that follows should in any way be construed as actual flight instruction. Furthermore, no PC flight simulator should in any way be considered a substitute for bona fide flight instruction from a certified instructor. And if you are not a qualified instrument pilot and deliberately fly a real aircraft into real instrument flying conditions, well, you pretty much deserve whatever happens to you, and the only tragedy is if you've talked some unwitting passenger into flying with you.

</obligatory disclaimer>

Choosing and configuring the flight simulator.

Chances are, if you own PC flight simulation software, it will be one version or another of Microsoft Flight Simulator. Version 98, 2000, and 2002 are all equally capable for our purposes here. MS Flight simulator is not the only package available, though. An outfit by the name of Looking Glass Technologies released a family of very capable programs under the title Flight Unlimited. You want either version II or III. You can also use X-Plane, produced by Laminar Research...which I have actually seen sold retail in Best Buy, but you're more likely to find only online. I am aware of at least one open-source project to develop a flight simulator, though I don't know the status. (Feel free to /msg me or add a w/u if you know more!)

You want to avoid trying to use one of the 'military' flight simulator programs; Falcon 4.0, Combat Flightsim, or the like...they don't have the features you'll need for the maneuvers described below.

You really must have a joystick. You'll only be frustrated without one.

You should not attempt instrument flight until you have familiarized yourself with the basic handling characteristics of your aircraft and simulator. Log a few hours flying around, learn to land without crashing. Only then can you begin to think about instrument flying.

For our purposes, set yourself up in the "Lear jet" class of aircraft. This may vary depending on which simulator you are using...I believe the "Flight Unlimited" series of programs has a Cessna Citation instead of a Lear jet.

Take off and climb to 15,000 feet. Turn to a cardinal heading (due North, South, East, or West). Maintain an airspeed of 200 knots. (We flew 250 in the Navy, but 200 seems to work better for my sim setup.) Set up your autopilot to hold you at this speed, altitude, and heading. Or, put the simulator on 'pause' before proceeding.

You can replicate instrument flight conditions on your PC simulator in a couple of different ways. All modern flightsim software offers the user a way to configure the weather. So you can set up a cloud bank from the ground to 20,000 feet. Or, at least in MS flight simulator, you can turn off the main view out of the cockpit window, leaving only the instrument panel and a black void where your normal view of the sky and ground would be. Take your pick...you want to FORCE yourself to read and rely on your instruments.

Now, here are the things you'll need to know:

Prioritize! Your job is to Aviate, Navigate, and Communicate in that order.

In terms you might understand from computing, your priorities will determine the 'time slice' proportion of your attention as you fly on instruments. If you can't successfully fly the aircraft, and keep it from spiraling in or stalling out, none of the rest of it is of any use. So your first priority is always to keep the aircraft safely flying. Only then do you devote 'cpu cycles' to the issue of where your plane is relative to locations on the ground (navigation). And only once you've got those covered do you concern yourself with talking on the radio.

Now, the 'Aviate' portion of this time slice is the thing we're practicing here under the rubrik of basic instrument maneuvers. And the 'Aviate' task, believe it or not, must be further sub-prioritized...

You must develop a proper SCAN of the flight instruments, giving first priority to the primary attitude reference instrument, the artificial horizon, also known as your attitude gyro.

All other aspects of flight performance proceed from the flight attitude of the aircraft in combination with the power output from the engines. So you must be on very, very close terms with your artificial horizon.

On any instrument capable aircraft this is always the most prominent instrument on the panel. On slightly older aircraft it is an analog device, looking like a large billiard ball, painted black on the lower half, trapped behind a glass window. There will be graduated lines painted on the surface of this ball, and a stylized representation of the aircraft as seen from the rear will be superimposed. On more modern aircraft this will be an electronic display projected onto a CRT.

The following are some ascii represenations of some typical attitude gyro presentations. (I apologize for the crudity, but ASCII art is not by best subject...)

Straight and level will look something like:

              -------------
             /             \
            /               \
           /                 \
          |                   |
          |                   |
          |----- ===v=== -----|
          |8888888888888888888|
          |8888888888888888888|
           \88888888888888888/
            \888888888888888/
             \8888888888888/
              -------------

...while a climbing left bank will look something like:

              -------------
             /             \
            /               \
           /                 \
          |                   |
          |                   |
          |--    ===v===      |
          |88---              |
          |88888-----         |
           \888888888----    /
            \888888888888---/
             \8888888888888/
              -------------

...Hopefully you can get the idea. The attitude gyro is your window out onto what the horizon would look like if you could see it. As such, it has to be the "hub" of your scan. In other words, as you fly instruments, your eyes (and attention) will continually bounce in a scan pattern something like the following:

Attitude gyro - altimiter - attitude gyro - airpeed indicator - attitude gyro - compass - attitude gyro - vertical speed indicator - attitude gyro - VOR/TACAN/DME/ADF/GPS (radio navigation instruments, which we're ignoring in this wu) - attitude gyro - engine instruments - attitude gyro - ...and so on.

You must learn to maintain your scan, and devote an appropriate slice of attention to each aspect of flight. Your instructor can easily tell when your scan begins to break down...your heading and airspeed will be optimum, but your altitude will sink or zoom. Or your altitude and airspeed will be fine, but you'll drift off your heading. It takes practice, and that's what the maneuvers described later are designed for.

You must constantly trim, trim, TRIM the aircraft. This is important at any time while flying, but is simply critical in instrument flying.

Trim tabs are the tiny control surfaces within the larger, main control surfaces. Examine an airplane's tail surfaces some time. Identify the elevator, or main horizontal control surface on the tail. Chances are there will be a smaller rectangular piece cut out of it...this is the trim tab, and is adjustible from within the cockpit.

These are adjusted by the pilot to remove the forces he/she must apply to the control stick or yoke to maintain level flight, which vary widely according to flight conditions of airspeed and altitude.

For example: You're in level flight at 200 knots, 15,000 feet. You find that you must maintain constant back pressure to maintain level flight...if you let go of the stick, the nose of the plane wants to pitch downwards. So you adjust the elevator trim to reduce the required stick force until you can let go of the stick and the airplane maintains a constant attitude.

Now, say, you want to speed up to 250 knots while maintaining level flight at 15,000 feet. You add throttle. As the airspeed creeps up, you find the trim setting that was appropriate at 200 knots is no longer appropriate; you find the aircraft's nose wants to zoom up. You must add nose down trim to compensate.

The upshot is that flight is a dynamic, constantly changing set of parameters, and you must constantly RE-trim as appropriate; you will not be able to set trim once and forget about it. Trimming the aircraft will be almost constant, and must become almost subconsciously automatic.

In just about all tactical military jet aircraft the main trim control will be an electric switch mounted on the control stick...the "coolie hat" switch many of you have on your PC joystick. Now, by default for MS flight simulator the joystick hat switch is configured to control your view direction, and trim is actuated by some keyboard buttons, by default tne 1 and 7 keys on the number pad. You can re-map the trim to be operated by the hat switch if you want. Whatever control actuates the trim (the aileron and rudder axes also have trim controls, but the elevator trim is by far the most important) you must know it cold, and you must be constantly trying to trim the aircraft until it will fly 'hands-off' in all flight regimes.

The First Maneuver - Level Flight

Now, let's give it a try. Take your simulator off 'pause' or de-activate the autopilot. Maintain level flight on your chosen cardinal heading. Try to keep deviations in altitude to plus or minus 100 feet. Keep your heading within 3 degrees either side of N, S, E, or W. Not easy is it? Think you've got the airplane properly trimmed? Let go of the stick. Does the nose rise or drop? Re-trim until it doesn't. Do this for a couple of minutes. When you think you've got the hang of it, start bringing your airspeed into your scan. Add power if slow, reduce it if fast. You have to remember to RE-set the power once your airspeed is back to the 200 knots you started out with. What level of power is appropriate to maintain this speed? I could give you some metrics - throttle settings in terms of pounds per minute fuel flow that you could use as a starting point. But you know what? I'm not going to. I'll tell you what my instructors always used to tell me - you don't learn to fly by memorizing numbers; you use whatever power level is appropriate. You make a setting, scan the airspeed indicator in a couple of seconds to see what the result was, and RE-set. You'll make a series of corrections that should get smaller and smaller and converge to the proper power level to maintain 200 knots in level flight at 15,000 feet. While you're doing this, you're maintaining your scan. Keep altitude within 100 feet of 15,000, heading within 3 degrees of your chosen cardinal heading, airspeed within plus or minus 5 knots of 200. No, it's NOT easy. But the rest gets even harder. You should be fairly capable of maintaining these parameters before you proceed to the rest of the maneuvers...

The Second Maneuver - The Constant Rate Turn

The constant rate turn would, in real flight instruction, be called a standard rate turn, becuase it would be made with reference to yet another instrument, the turn-and-bank indicator. Classicly, this is a compound instrument consising of 2 parts: a ball in a fluid-filled, spirit-level type apparatus and a vertical needle resembling that of a metronome. It has been used as a backup for the main attitude instrument, the artificial horizon, but is more typically used to gauge turn rate and turn coordination. An uncoordinated, skidding or slipping turn will cause the "ball" portion of the turn-and-bank indicator to be off-center...which is a signal that the pilot is not applying an appropriate amount of rudder input for the turn.

For instrument flight, the "needle" portion of the turn-and-bank indicator comes to the fore...it measures the angular rate of your turn. This instrument will almost always have a gradation or indicating mark indicating a "standard" rate turn, which will yield a 360 degree turn in 2 minutes.

Now, having said all of that, I realized that you can't use it for this maneuver if you are flying the Learjet in MS flightsim...I could find the "ball", but the "needle" was not to be found. (The "needle" IS on the panel of some of the other aircraft in MS flightsim, and may be present if you are using another sim program). So we'll have to approximate this for the purposes of practicing constant rate turns. Here's how you do it:

Begin in straight and level flight, 15,000 feet on a cardinal heading as before, with airspeed constant at 200 knots. Watch your clock, and wait for the next half-minute mark...0 or 30 seconds. One to two seconds prior to this mark, roll smoothly but authoritatively in either direction, your choice, stopping at just over 30 degrees angle of bank. The nose of the aircraft will most likely want to drop, so you'll have to add in a judicious amount of "back-stick" pressure to maintain level flight. Remember to SCAN-SCAN-SCAN. Hold a constant angle of bank, within plus-or-minus 100' of 15,000 feet altitude. The extra induced drag will also tend to slow the aircraft, so you'll have to add a small bit of throttle to maintain within plus or minus 5 knots of 200.

The key to a constant rate turn is to check your progress every 15 seconds. If you're "behind schedule", increase angle of bank another 5 degrees. If ahead, reduce it. Try to arrive at the 180 reciprocal of your original cardinal heading after one minute, having maintained a constant altitude and airspeed.

You can try different variations on this maneuver...turns to either side, continuation of the turn for a full 360 degrees in 2 minutes, reversing the direction of turn after 180 degrees. You could also try a "half-standard rate" turn...180 degrees after 2 minutes, 360 after 4. Is your hand tired from squeezing your joystick after one of these maneuvers? You're probably not trimming enough...you should be able to smoothtly fly with the gentlest pressures on the stick if you trim well enough. Do a half hour of these before proceeding to the next maneuver...

The Third Maneuver - The "S-2"

The "S-2" maneuver tests your ability to controllably maneuver in the vertical plane. As before, begin in straight and level flight on a cardinal heading, 15,000 feet, 200 knots. Once again, wait for the next half-minute or whole minute mark. Two seconds prior, reduce power and push the stick forward to drop the nose of the aircraft. But only a little bit! You're aiming for a steady-state, 1000 foot per minute rate of descent, as measured by your vertical speed indicator, or VSI. How much power do you pull off? In the Learjet, it will be a few hundred pounds-per-minute fuel-flow reduction on each engine, but once again, don't fly to memorized numbers here, learn to correct and re-correct as appropriate. You want a 1000 fpm rate of descent, constant heading, constant airspeed. Here you learn how power and attitude are coupled...you must make appropriate adjustments in both pitch attitude and power. If you simply lower the nose, your airspeed will increase beyond 200 knots. If you reduce power without an appropriate pitch attitude adjustment, your airspeed will decrease too much. Once again, you must SCAN-SCAN-SCAN to correct and RE-correct as the maneuver progresses. Check your progress every 15 seconds. After 30 seconds, you should be at 14,500 feet. Are you descending too fast, but maintaining the proper airspeed? Add a little power and, simultaneously, add "back-stick" pressure to reduce rate of descent while holding airspeed constant. Good rate of descent, but airspeed too slow? Add a little power and add "forward-stick" pressure to increase airspeed while holding descent constant.

At the one minute mark, you should be 1000 feet below your initial altitude...still at a constant 200 knots, with heading steady on the cardinal heading you began with. And here it gets tricky: you're going to add power and increase pitch attitude to establish a 1000 fpm rate of climb. And you spend the next minute doing the exact same things in the opposite vertical direction. So, after a total 2 minutes elapsed, you should once again be at 15,000 feet, 200 knots, on the same cardinal heading. Try to level off, reducing power so that your airspeed remains "pegged" at 200.

This is a more difficult maneuver, and you may have to practice some hours worth of these to truly get the hang of it. You must constantly scan, and constantly trim, to have any hope of getting even close. One advantage you will have, however, over a real aircraft: On real planes, your VSI will "lag" several seconds after you change from level flight to descent, from descent to climb, and from climb back to level flight. Not on MS flight simulator, however. In what is to me one of the most glaring differences between the simulator and a real aircraft, the flight simulator VSI always responds instantly and accurately to what the aircraft is really doing. And this, in turn, makes this kind of maneuver easier than in the real plane.

The Fourth Maneuver - The "S-3"

In the S-3 manuever, you put it all together. This is the most demanding basic instrument flight maneuver, and if you can do one of these well, you are almost ready to begin work with precision approaches.

Beginning with the same parameters as always, level at 15,000 feet, airspeed 200 knots, established on a cardinal heading, you start once again at a half-minute or whole minute mark. You reduce power, lower the nose of the aircraft, and roll to a 30+ degree angle of bank simultaneously. And you shoot for a constant rate turn, steady-state 1000 fpm rate of descent. Check your progress every 15 seconds. Scan, Scan, Scan, Trim, Trim, Trim. At 30 seconds, you should be 90 degrees off of your original heading, 14,500 feet altitude. At one minute, you should be 180 degrees off original heading, 14,000 feet altitude. At this mark, add power, raise the nose of the aircraft, and reverse the direction of your original turn...and climb and turn back to your original heading and altitude, so that, at 2 minutes, you are back at 15,000, on your original heading, and at an airspeed that has remained throughout the maneuver within 5 knots either side of 200.

The Fifth and Final Maneuver - Transition To and From the Landing Configuration.

We're almost done, but you must practice one more thing before you proceed to precision ILS approaches, the kind that allow you to find the runway and land with a 200 foot ceiling and half-mile visibility.

Begin as before...15,000 feet, cardinal heading, 200 knots. Pull the throttles all the way back to idle. You will begin to decelerate, and you want to maintain constant altitude...so you want to gradually feed in back-stick pressure and/or nose-up elevator trim to resist the aircraft's natural tendency to nose down and descend. So, once again by way of a diligent scan and constant trim, maintain level 15,000 feet and monitor your airspeed as it decreases. At 170 knots, lower the gear and lower flaps one notch. (On the Learjet, this is 8 degrees flap extension.) Your trim will be disrupted by this...so scan and re-trim to maintain level flight. You will decelerate more rapidly...don't let this get ahead of you! At 150 knots, lower flaps another notch, to 20 degrees. Continue to decelerate to an airspeed at which a landing approach can be made...for our purposes here, use 125 knots. You'll have to come back up on the throttles to "catch" your deceleration. Trim, trim, and re-trim, to maintain a steady 15,000 feet of altitude at 125 knots. If you go too low, add more power. Trim the aircraft so that it will fly hands-off in this configuration. Try some gentle left and right turns...you'll have to add power during these to maintain speed and altitude. Try some gentle descents, such as you'll make on a precision approach to a runway: reduce power and lower the nose to enter a 700 fpm rate of descent...still maintaining constant airspeed and heading. When you're bored with this, "clean-up" the aircraft. Add full throttle and RAISE the landing gear. You'll almost immediately have to add nose-down trim to keep from zooming above the level attitude that you are still trying to maintain.

And now that you've been introduced to the maneuvers...

Log about 12 hours worth of 'em. I had to. Actually, that was 12 hours each in the primary (T-28), intermediate (T-2), and Advanced (TA-4J) parts of the syllabus. So do 36 hours worth.

And when you've demonstrated proficiency with these, you're ready to move on to more advanced navigation topics. VOR, DME, ADF, GPS, ILS, these are all acronyms. For stuff you'll learn in your quest to become a real instrument pilot.

----------------------------------------------------

Late update...Thanks to JerboaKolinowski for reminding me of the Flightgear project. This is a free, GPL'ed flight sim for Linux. According to JK, "Certainly worth a namecheck here, I'd have thought." Right you are, JK, and touche'.

The project has a website at www.flightgear.org. Check out the screenshots, and give it a try if you've got a rig that will run it. We must encourage projects like these, it makes it better for us, the flight sim consuming public.