Flight Simulator Co-Pilot

by Charles Gulick

Big Wheels

Tweed-New Haven Muni, CT to Boston Logan, MA

North: 17346. East: 21322. Altitude: 13. Pitch: 0. Bank: 0.
Heading: 220. Airspeed: 0. Throttle: 0. Rudder: 32767.
Ailerons: 32767. Flaps: 0. Elevators: 32767. Time: 5:40.
Season: 3. Cloud Layer 1: 3500, 2000.
Surface Wind: 5 kn., 190 deg.

Why do I start a flight like this at daybreak? It's not because I like getting up in the middle of the night. It's so that no matter how lost we get, we'll surely arrive where we're going by cocktail time, twelve hours from now, which I don't intend to miss.

Your going to learn a great deal today: including how to fly in and over weather and how to use your NAV (for NAVigation) radio to fly OMNI radials.

Before we take off, go into radar and zoom out until you can see a strip of land to your left across the water. The land is Long Island, and the water you'll take off over is Long Island Sound. The notch of water to your right is New Haven Harbor. Across the harbor is West Haven, and at the top of the notch is New Haven, Connecticut, home of Yale University. New Haven was a seaport in colonial days. And it might interest you to know that in 1883 there was a bewitched house on Church Street with sounds of tramping feet and objects flying around. A sick woman was stirring a cup of medicine and the spoon flew away. Then apparently something shot at at her, because there was a bullet hole in a window. But no bullet was ever found in the house.

The highway you see is Interstate 91. Switch to the out-front view, and get ready for your takeoff on Runway 20 (ahead of you, as you can see).

Put on your power and roll whenever you're ready. Make your regular departure takeoff and climb-out—rotate at 80 KIAS (one notch of back pressure, which you ease off again as soon as the VSI indicates a climb), dump your flaps when you're climbing better than 500 FPM, flatten the climb with two quick presses of down elevator in Cessna and one press in Piper, followed by a four-notch power reduction to 2105 RPM in Cessna, and a two-notch power reduction to 2250 RPM in Piper.

See how easy it is? You're soon climbing at 500 FPM. (By the way, the only difference between the departure takeoff and climb-out, and the technique you use when flying a pattern, is the flattening of the climb. When you're going to fly a pattern, keep the climb steeper and the airspeed slower, so that it's easier to transition to straight and level at pattern airspeed.)

Climb straight on out until you're in the overcast (bottoms are at 2000 feet). Long Island will become visible on your way up.

Level off at 2200 feet, using a power reduction of two notches for 1905 RPM in Cessna, and three notches for 1950 RPM in Piper. Make the reduction when the altimeter reads about 20 feet (one mark) under 2200. Don't touch your elevators.

Now consider: You're not flying “blind” in this overcast. You know exactly what you're doing. Everything is under absolute control. Your airspeed is right where it ought to be. Your attitude is level on the horizon. Your altimeter confirms that you are straight and level at 2200. You're not climbing or descending, and your Vertical Speed Indicator says the same. Your heading is what it was when you took off—within a degree or so of 200. Your turn indicator shows no bank, no turn. You are straight and level. Who needs the outside world when you have all those references right in front of you?

Now, as you fly, tune your NAV1 radio to a frequency of 110.0. If you don't know how to do this, use the Pause key and look at the directions in your manual. Then press the Pause key again to resume flying, and tune in 110.0.

Now check your DME reading. It's somewhere in the vicinity of 50. Is the number increasing or decreasing?

So now you know that whatever VOR station I had you tune to, your present heading is taking you where—away from, or toward it?

The VOR station, or OMNI, can be visualized as a big wheel with 180 spokes radiating from its hub. In the simulator the spokes are spaced two degrees apart, spanning a complete 360-degree circle. The wheel does not turn; it is you and your aircraft that are moving. You are somewhere in relation to one or two of the spokes of the wheel, moving like a spider on a web, straight out along a spoke or strand, or diagonally between two of them, headed from one to another.


Figure 12-1. VOR Station and Radials

In a sense, the OMNI knows you're there, because you're within its range. If you were not within its range, you'd have no reading on your DME. Nor would the OBI needle have shown any activity when you tuned the station. But it did. It swung way over to the right and pinned off-scale. No matter that it pinned; its reaction acknowledged your presence.

Now, if your observation of the DME told you that you're flying away from the station—away from the hub of the wheel—you read and interpreted it correctly. The DME always reads your distance in nautical miles from the VOR to which your NAV1 is tuned.

And yet, you say (if you're doing your instrument scan), the OBI reads TO. How can you be flying away from the hub when the OBI says TO?

Simply because the OMNI station, though it knows you're flying somewhere along or between its spokes, doesn't know which way the nose of your plane is pointed. It knows where you are, but not where you're headed. The OMNI doesn't know anything about headings; it deals with being. The TO is telling you not that you are flying to the station, but that from where you are now a given radial is your most direct route to the station.

Now let's find out on what FROM radial we are flying away from the VOR.

Observe your OBI (Omni-Bearing Indicator, OI' Big Eyes) and advance the OBS (Omni Bearing Selector) headings gradually, watching for the OBI needle to get into action. Note that in the vicinity of 60 degrees it comes on scale. Stop a moment when it's centered—probably somewhere around 70 degrees (the readout you should be watching is the one at the top of the OBI).

Now, you might be inclined to believe that, because the OBI needle is centered at, say, 68 and reads TO, you are headed straight for the hub of the wheel, along spoke 68. Not true.

What the OBI is now telling you is that if you were to turn to a heading of 68 degrees and then correct to keep the needle centered as it is now, you would be on the 68-degree radial headed for the station. The OBI does not tell you in what direction you're heading or, until you set it to do so, what radial you may be on or crossing. The fact that your heading indicator (down there under the artificial horizon) says that you're heading around 200, which you are, has absolutely nothing to do with radial number 200 emanating from the VOR station. A heading of 200 is just a heading of 200; it's not a radial. You could be on any heading and on any radial, with nothing in common between them until you position your aircraft so that your heading and the radial and the OBI needle are in agreement or, in the event of significant wind, near agreement.

But we were going to find out on what radial we were flying from the station. So keep advancing the OBS. The needle soon goes as far as it can to the left, but continue to crank the selector around. Somewhere near 148 degrees, the TO disappears and is replaced by an OFF indication, which lasts through about 20 degrees while the VOR turns its thinking cap around. Then FROM appears—we must be getting warm. Persist in cranking the OBS until the needle is centered. Now you can read the FROM radial you're on or intersecting at the moment.

Notice that the reciprocal of the radial—the lower reading on the OBI—is close to the TO radial you were reading earlier. If the TO radial was 68, it's now 244, the reciprocal of which is 64. The reason for the four-degree difference is that you've been moving while you did all this. Obviously, you've moved to a new location in relation to the spokes of the wheel.

Once again, set up your OBI to center the needle with a TO indication. Now start a standard-rate turn to the left, using a 20-degree bank (and one notch of back pressure, remember, to hold your altitude), to the heading your OBI indicates. I can't tell you exactly what that is, because you're doing the flying, but it's probably somewhere in the vicinity of 60 degrees. Don't take my word for it, however; fly the heading indicated by the OBI with the needle zeroed. Remember to take off the back pressure you applied before the bank.

Once you're level, did you lose or gain any altitude in the turn? If so, use power (and power only, one notch of it) to get back to 2200 feet.

Chances are excellent that your OBI needle is not centered. Your job now is to get and keep it centered. The OBI—not the heading indicator—is your primary directional instrument from now on. If the needle isn't centered, you're not on the radial you're trying to fly. Use a little aileron, in the direction the needle is offset, to bring it back to center. Don't expect immediate results in your flying; it takes time for the airplane to turn back toward, and then fly to intersect the radial. You have to anticipate in both cases. Be conservative. Remember to correct your heading toward the needle—“fly the needle”—in all cases. When 1) the needle is centered, and 2) the OBI indicates TO, and 3) the radial you have selected and your regular heading indicator agree in principle, and 4) everything stays relatively steady, then and only then are you right on the spoke of the wheel, heading toward the hub, which is the VOR station. You'll fly right over or within a few hundred feet of it. If the OBI needle departs from center, make the necessary corrections little by little. Then wait, and make additional small corrections, until the needle is centered. Then turn immediately to the heading to which the OBI is set and see how you're doing when things settle down. The wind direction may require you to maintain a heading to the right or left of the selected radial in order to stay on it. That's what we call “crabbing,” because it's akin to the way a crab crawls.

Now when you're right on, needle centered, altitude 2200, straight-and-level, and feeling very confident, wake me up.

Contact Bridgeport tower on your COM radio and get a weather check. The tower frequency is 120.9.

Let's climb to 3700 and see some blue sky. Don't use any elevator, just power, the way you learned it—two notches in Cessna, three notches in Piper. That will give you a fine 500 FPM climb.

At 3700, take off the power you put on to climb and see if your airplane holds the new altitude. If the VSI doesn't settle on zero (give it a chance to), you need more power at 3700 than you did at 2200. So use it—no trim, just a notch of power.

Keep flying. As you get close to the Norwich OMNI the OBI needle will start hopping around and then point hard right or left. The reason is that the spokes are getting closer together as you near the hub, and several radials are affecting you simultaneously. Then at 0 DME the needle pins in the direction of the actual location of the station. Watch while the OBI switches from TO to OFF at 0 DME and then to FROM. Don't chase the needle when you're close to or over the station. When you get a few miles out, it will gradually come back on scale. You'll be in the same relationship to the radial as you were before, but bearing FROM rather than TO the station.

What's happening to your altitude? Keep your aircraft at 3700 feet, not 3900 feet. Stay on top, not sixty feet under.

Now we're going to let down into the overcast again, to our earlier altitude of 2200. Give me a 500 FPM descent, and as you do, tune Boston VORTAC on 112.7. Set the course selector (the OBS) to 68, and make whatever (gentle) turns are necessary to center the needle and fly it. Don't forget back pressure before you turn, and let it off when you are level. I don't want to see any ground; I just love all this gray stuff up here.

(Piper, if you get in trouble around here, check your fuel; you can't fly on one wing—particularly if it's empty.)

By the time you level off at 2200, you should be heading about 68 degrees with the OBI set to 68 exactly, the needle centered, your elevators at operational neutral, your throttle at whatever cruise RPM will hold your altitude, your VSI on zero, and straight and level confirmed everywhere.

Meanwhile, please don't spill the coffee I'm handing you.

Have you got a match?

We're inbound for Boston's Logan Airport. Contact the control tower on 119.1. Start your let down when your DME reads ten nautical miles from the VORTAC. The station is right at the airport. Remember, use just a power reduction to enter your 500 FPM descent—two notches in Cessna, four notches if you're flying Piper.

Logan should be directly ahead of you when you get below the overcast. When your altimeter reads 1000 feet, transition to straight and level slow-flight. You know how to do that from a climb, but not from a descent, so let's learn:

Cessna, reduce your power another two notches, to 1505 RPM, and apply—two at a time—six quick notches of up elevator.

Piper, reduce your power another three notches, and apply—one by one—four notches of up elevator.

You've made the transition to slowflight.

Our runway at Logan is 22 Right. Because Piper is low on fuel, we're approved for a right turn to the crosswind leg, which heads 130 degrees. Make this turn shortly after you cross the highway, which is Interstate 93. Take a look out the left side and get the lie of the runways, then turn left to downwind leg, 40 degrees, and make your normal pattern landing.

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