New Pilot

From mundane to menacing in seconds

The pilot offered up a briefing on the flight conditions that could be expected for the proposed photo shoot. It was a fine day for pictures, but the air above the seaside village was choppy. The pilot urged the young man with the camera to consider whether his two small daughters would be comfortable in the turbulence pilots had been encountering in the vicinity all day.

The decision was made to launch with all four aboard. The flight would progress south, just off the coast, until reaching the village. Then it would wheel westward, toward a 1,500-foot mountain just beyond the village, then turn north, back to the airport. The pilot leveled off at 1,200 feet. The persistent chop that had marked the day's flying was still there. As the photographer clicked away from the right front seat, the pilot glanced rearward and noticed that the little girl in the right rear seat wore the downcast look of someone who would rather be anywhere else than in the bouncing Cessna Skyhawk. Their eyes met for an instant, and hers were big with fear. Concerned, the pilot concentrated on executing a smooth, gentle turn onto the western leg of the photo run.

The twin jolts that battered the aircraft in the next split second were among the worst the pilot had ever experienced. Was it a downdraft off the mountain, which now filled the windscreen at 12 o'clock and a mile? No time to wonder. Recovering to straight-and-level flight, the pilot quickly glanced around the cockpit, and his gaze again froze upon the unhappy girl in the rear seat, now clearly frightened to the point of speechlessness. The pilot knew he must conclude the flight and return her to the ground at once. He turned to shout his intentions into the girl's father's ear, but as he began to speak, the airplane became one with the mountain.

It's solo day, and so far, the cross-country has gone exactly as planned. Access to the Class C airspace has been granted without fuss, and the student pilot is in a relaxed mood as he maneuvers to comply with approach's instruction to enter a right base leg to Runway 29. Pre-landing checks done, flaps deployed, aircraft trimmed. Nothing to do now but land and find the FBO. Suddenly, the radio crackles to life.

"Cessna Five Six Five, change of plans: Can you accept Runway 18?"

Umm, affirmative.

"Cessna Five Six Five, enter a left base to Runway 18, traffic is a DC-9 on a 3-mile final to Runway 29, Tower will keep you advised. Contact Tower now on 120.9."

Umm, Tower, Cessna Five Six Five is with you.

"Cessna Five Six Five, cleared to land Runway 18, hold short of the intersection of Runway 29, traffic is a DC-9 on a 2-mile final."

The student pilot turns final, but realizes to his dismay that his groundspeed, absent the headwind that a landing on Runway 29 would have provided, has increased. Idling the throttle and lowering the nose in a frantic attempt to land reasonably close to the touchdown zone, his trainer enters ground effect and floats. Approaching the forbidden intersection, the student initiates a go-around, as a large silver airplane fills the windscreen....

Do I have your attention? Good, because the topic of today's lecture, as you may have already guessed, is distractions. Everybody knows that distractions are bad business; few pilot trainees let themselves get tripped more than a couple of times by an instructor asking the time- tested question, "What's the first thing you do when you are flying along and the _____ fails?" (It's a trick question because whether it is the engine, the gyros, the radio, flaps, or any other component that has failed, the answer is always the same: Fly the airplane.) What classroom chats and trick questions can't emphasize as well as real-world examples is that a pilot may have only a few fleeting seconds to carve up his or her attention into the necessary divisions, and properly execute the required procedures. A passenger on the verge of panic, for example, is every pilot's nightmare. But if the passenger's panic attack begins when the aircraft is pointed at a mountain, well, first things first. A student pilot's budding complacency about a cross-country may set him up for problems if a sudden change of plans robs him of his ability to think through a new task for which he has accepted a clearance.

The airplane didn't really hit the mountain. Back up the videotape replay a few seconds, and bank the aircraft away from the mountain before informing the gentleman in the right seat of your intentions to terminate the flight, and you'll have what actually took place that day, because I was there, and I know. The five-minute return flight to the airport seemed like an hour with the frightened children hyperventilating in the second row. And her father, who in his eagerness to take pictures had grossly miscalculated his daughter's capacity for flight, wasn't much of a flight nurse, either. What the situation could have become, rather than what it was, occupied my thoughts as I drove home from that handsome summer day of for-hire sightseeing flights.

No, the student pilot arriving at the airport in Class C airspace didn't really have a close brush with the DC-9 landing on the other runway. What he had, instead, was an unexpected lesson in slipping an airplane to lose altitude. In the terminal, after landing, we discussed the scenario presented above: how things might have gone had the distraction been inflicted on a poorly prepared pilot.

Not all distractions come upon you suddenly in flight. Some are loaded aboard the aircraft by the pilot in command. The high-gear businessman arrived at the airport for a dual training flight scheduled to begin at dusk and progress into a session of night pattern work. But the FBO had dropped the ball. Neither of the two Skyhawks was ready for flight, and by the time the pilot and instructor had attended to line chores, darkness had fallen. Distracted, disappointed, and angry, the headstrong gent forged ahead with the flight, but found himself no match for the marginal visibility and quartering crosswinds served up that hazy evening. He cut it short and returned to fly another night.

How often do you see a DC-3 on amphibious floats taxi past? The only time you will see one is when N130Q, based in Greenville, Maine, happens to land at your airport. When it does, it will definitely get your attention (read: distract) and did so one fine summer day while a student pilot was up on a ladder, preflighting a high-wing trainer. He stepped down to stare — who wouldn't — and several minutes elapsed before the Water Gooney waddled away and he resumed the preflight. Had I not cast my usual glance around the aircraft before boarding, he would have taxied off with the left fuel tank cap sitting upside down on top of the wing, where he had left it when he descended the ladder to watch the unique airplane enter the ramp.

No one is exempt. A friend asked me to fly a 20-year-old Cessna 172 with him on a pre-purchase check. Lowering 10 degrees of flaps to depart the narrow 1,800-foot grass strip via the soft-field method, I coaxed the Skyhawk into ground effect and held it there to gain airspeed, while concentrating on maintaining directional control, until stiffness in the control column told me it was time to climb out. Once clear of the narrow departure corridor, then — and only then — did I glance over at the airspeed indicator: It was pegged on zero. No airspeed. Obviously a pitot- tube blockage deep within, where the preflight had not detected it. Fortunately, I have spent many hours practicing maneuvers with the airspeed indicator covered — and I make students do this in dual sessions so they will be able to fly the airplane properly in the event of an airspeed indicator failure — so that wasn't the problem, just the set-up. The gotcha surfaced when I leveled off at 2,000 feet and trimmed for cruise, which seemed to take more than the usual effort in a 172. That's when my friend said, "When are you going to retract the flaps?"

Another day, another distraction. I was homeward-bound on a short cross-country undertaken on personal business. A student pilot had accompanied me for the trip in a Cessna 152. It was a mild day with light traffic and no wind, and my student, who was flying, had gotten to see how much fun it is to fly somewhere instead of driving. Entering the downwind leg, he reduced power, checked airspeed, added a notch of flaps, and retrimmed. Turning base, he set the flaps at 20 degrees of deployment. But the flap-position indicator didn't budge, and Rick sensed the absence of the tell-tale pitch-up that accompanies flap deployment on a high wing. He gazed at the flap-position indicator, then out at the wing, then back, in mounting confusion. Meanwhile, the airplane was still responding to the most recent pilot inputs and was heading off on a course somewhere between the base leg and the final approach, to which a turn had been begun but not completed. "Fly the airplane," I said. "Land with 10 degrees flaps and we'll see what's wrong once we're on the ground." After we landed — a little long and a little fast — the switch behaved normally. And although an otherwise perfect flight had been blemished by a spiteful little gremlin that had done its dirty work and vanished, I was grateful as an instructor that a fine lesson about distractions had been presented on a day when the student thought school was out. Just like in real life.

Dan Namowitz is a multiengine-rated commercial pilot and CFII living, flying, and instructing in Maine.

How It Works: Gyro Patter

Gyro instruments don't have to be Greek to you

BY MARC E. COOK

Thank Jimmy Doolittle. In September 1928 he first tested some revolutionary new instruments, items that would allow improved situational awareness for the pilot and safe passage through clouds. Those two advances were the precursors to the modern gyroscopic attitude indicator and directional gyro, the two main devices in the instrument pilot's arsenal.

Today we take a full gyro panel for granted. Even the most mundane trainers come with a standardized package of attitude indicator (AI), heading indicator (HI), turn coordinator (TC), or, in its place, a turn and bank (TB). Together with the pitot instruments — airspeed indicator, altimeter, and vertical-speed indicator — the gyro system allows precise and safe trespass through the clouds.

Gyro instruments work on the principle of gyroscopic inertia. Inside each of the gyro devices is a spinning wheel or disc. Its inertia, once the wheel has been accelerated, tends to keep the disc stable about its axis of rotation. You may have picked up a bicycle wheel by the axles and tried to deflect it side-to-side while it was spinning; you would have noticed that it initially resisted the movement. That's the same principle used by the gyro instruments. Once the instrument is stabilized, say in level flight, any deviation in flight path will try to deflect the gyroscopic wheel in its gimbal mount. This movement — which is, in truth, the instrument case changing position relative to the gyro wheel — is translated to movement of a needle or card on the instrument's face. The gyro wheel is said to have stability in space.

While the three main gyro instruments use the same principles, there are significant differences inside the cases. The artificial horizon, for example, contains the gyro wheel spinning on the vertical axis. One basic gyroscopic concept is precession — any force applied to the gyro will result in movement of the gyro wheel 90 degrees out of phase. This dictates how the gyro disc is connected to the indicating mechanism.

In the AI, the gyro wheel is free to move about two axes, thanks to the construction of its gimbal mount. This means simply that the gyro is being held by an apparatus with pivots in two axes, which provides for both pitch and roll information on one instrument.

The heading indicator, on the other hand, places its gyro wheel spinning on the horizontal axis, the pivot aligned with the aircraft centerline. Its gimbal allows only one axis of freedom (vertical) and connects the mount to the card on the instrument's face through bevel gears. When the airplane begins to turn, the compass card on the front will begin to turn only when the gyro reacts to the yawing of the airplane during the turn.

Gyro instruments react to short-term movements of the airplane. In fact, the attitude indicator contains a set of weights intended to drive the instrument toward level flight by sensing gravity. These weights move the instrument face about 3 degrees per minute. So if you were to maintain a 30-degree coordinated banked turn for 10 minutes, you would look down to see the AI indicating level flight. Likewise, the heading indicator will succumb to precession, moving from the set magnetic heading over time. That's why you should periodically check it against the wet compass to make sure you're still on track.

Commonly, the AI and HI are powered by vacuum pneumatic systems. Along the periphery of the gyro disc are small, cup-like cutouts. A tube aligns incoming air pressure to act on these cutouts to spin the gyro disc. By evacuating the instrument chamber with help of the vacuum pump, ambient-pressure air comes rushing in, propelling the gyro wheel. This wheel spins quite rapidly, typically 10,000 to 15,000 rpm.

Most modern airplanes use engine-mounted vacuum pumps. They are simply ellipsoidal chambers into which is fitted a circular drive hub. Protruding from this hub are a number of carbon or aluminum plates, or vanes. They are free to move inside the hub's slots, drawing in air from one port and forcing it out another. Typically, the pneumatic system is connected to the port that is drawing in the air, hence the name vacuum system. Some airplanes do the reverse, providing pressure to the gyros on the panel; this is called a pneumatic-pressure system.

Why use suction at all? In the event of a vacuum pump failure, debris will not be scattered through the system and deposited into expensive, sensitive instruments. There is a filter inside the cabin that removes particulates from the air going into the gyros. It's generally true that the gyros will lead shorter lives in a smoker's airplane.

Since the AI and HI are usually powered by the same pneumatic system, it's prudent to have another gyro instrument independent from them. That's the turn coordinator or turn and bank, either of which is usually powered electrically.

The turn coordinator is the more recent development. Its gyro wheel spins on the horizontal axis, but the pivot is oriented transversely, parallel to the wing span. The turn coordinator's gimbal mount therefore runs along the airplane's longitudinal axis. In the turn and bank, this gimbal axis is perpendicular to the instrument face, meaning that the needle will show only movement in the yaw axis, or the pure turning of the airplane. The turn coordinator has its gimbal mounted 30 degrees off the longitudinal axis, meaning that it senses some portion of the rolling required to initiate a turn. This makes the TC a bit more sensitive. Both instruments are marked in what's known as a standard-rate turn, or a 2-minute turn. Hold the indicated markings for 2 minutes and you'll have made a 360-degree turn.

General aviation has been using gyro instruments long enough to have the bugs pretty well worked out. Notice on the ground how the instruments respond — those indicating movement about the yaw axis should move freely during taxi, and the AI should show any changes in pitch, such as you might have traversing the potholes in front of the FBO. If you hear one of the gyros whining over the sound of the engine, it's a good bet the instrument will not be long for this world. Also be alert for proper suction indications for the pneumatic instruments; the gauge should be in the green arc not far above idle speed and most definitely by the run-up rpm. Watch for too high an indication as well as one below the green arc; too much suction can spin the gyros beyond their design limits. Don't forget, too, to include the suction gauge in your scan while practicing on the instruments — vacuum pumps give little warning before they fail suddenly and completely.

Fears of Flying: The Solo Cross-Country Flight

BY JOHN F. CAMPBELL

It seems that the ritual of earning one's private pilot certificate requires the endurance of at least one more-than-memorable experience, one which provides rich, raw material for later hangar flying. Fitting that description was my long cross-country flight. I set out from Wayne County, Ohio, for Adrian, Michigan, to Sidney, Ohio, then home to Wayne County — or so I intended. I briefed with my instructor, checked the weather, then preflighted the airplane. The only potential stressor known during preflight was the possibility of strong winds developing toward the end of the journey.

I was excited. I took off on the first leg from Wayne County to Adrian. Intercepting the VOR radial was accomplished without a hitch. As I tuned nav number two for a cross-radial to triangulate my position, I discovered that it was on the fritz. Running through the possibilities and risk/benefit calculations of continuing the flight without the number-two nav, I decided I could adjust and continue the flight.

I traversed the Toledo ARSA — now Class C airspace — without difficulty, finding my destination field easily. It was magnificent. When I looked over at the Hobbs meter to record my time on the first leg, I noticed it hadn't changed. Calmly concluding that it had failed, I determined it should pose no particular threat to the continuation of my flight. Then I realized that without the Hobbs, I could not prove the hours necessary to record the flight. As I dejectedly stared at the panel, my eyes fell upon the tachometer — my redeemer.

After a brief snack and topping the tanks, I took off to the south for Sydney. This leg was to be flown exclusively by pilotage, as there is a paucity of navigational aids along the route. It would be a beautiful flight over flat, lightly populated farmland in western Ohio. During climbout, however, I encountered turbulence. I thought it a passing disturbance and proceeded to locate my landmarks.

The turbulence persisted and no matter what altitude I tried, I felt as though I was in a popcorn popper. Though my stomach tends to be sensitive, I had never been bothered with airsickness while piloting; today I began to wonder if I might experience a first. Locating my second airport proved easy, though it took some effort to control my stomach.

The turbulent air at altitude should have told me something about potential conditions near the ground. After missing my first approach at Sydney, being too high and not aligned with the runway, I realized that I was dealing with greater winds, gusts, and a crosswind. With great relief, I finally pulled up to the pumps, filled the fuel tanks, and went inside to try to appease my independent-thinking, vindictive stomach.

Now I had to get home. I climbed back into the airplane and took off. Climbing to altitude, it was quickly apparent that the air was still roiling. I set up the VOR, intercepted it — or so I thought — and happily continued on my way.

Some minutes later, it became obvious that my checkpoints were not appearing as they should. After some rather bald excuses about why the checkpoints were not where they should be, I admitted to myself that I was lost. Well, not exactly lost. You see, as I like to explain to my wife, there are two kinds of lost: relatively lost, and absolutely lost. In this case, I was merely relatively lost, for I knew that I was somewhere in this 3-inch square on the sectional.

The admission put my stomach in high gear. Now, while trying to determine my location, I also had to decide how best to handle the increasing probability that I would need to dispose of unwanted stomach contents. I determined that I could slow the airplane down and easily open the window — that might work. However, I feared the most likely result of that course would be a soiled face and a messed-up back seat which I would later have to clean up. I reached behind the right seat and, to my relief, found a plastic garbage bag. (A good FBO is always prepared.)

About this time, I flew over a small airport and was sorely tempted to land there. I didn't have the courage, however, to walk up to the office and ask, "Where am I?" A better option, it seemed, was to use one of the many VORs in the area. It proved rather simple to locate and identify a VOR, then find myself on the proper radial. Success.

Well, not even that success calmed my stomach — the plastic bag was called upon to serve its noble purpose. Somehow, in my mind, the romance of piloting had heretofore not included trying to hold a plastic bag still over one's mouth while filling it — and simultaneously being bounced all over the sky, all the while assuring the airplane is in an approximately normal attitude.

I was almost home now. Though still being bounced around, my stomach was more relaxed. I could see my hometown — take a deep breath and feel good, I told myself. As I tuned to monitor the Wayne County CTAF frequency, I heard my instructor's voice calling my call sign. "What's going on?" he asked. After I answered him, he asked me where I was. "Right over Wooster, inbound," I proudly proclaimed. "You can't land here," was his reply.

What do you mean I can't land there? My stomach awoke from its calm slumber. He told me the winds had picked up and were gusting crosswind to the only runway. He was not going to let me land, but instead diverted me to Akron-Canton Regional Airport — a controlled field in an ARSA, with multiple runways, about 20 miles to the east.

Come on, stomach, you can do it. I scrambled around for the Airport/Facility Directory for the requisite frequencies before running into the ARSA. After telling Approach Control that I was diverting to Akron-Canton due to unfavorable winds at Wayne County, I was vectored for my arrival. In setting up for my landing, I realized that ATC had not cleared me to the runway most favored by the winds. It was one that would mean about a 40-degree crosswind. Oh, well. I was trained in crosswind landings, and I wanted to get the airplane on the ground. The landing was picture perfect.

My instructor drove to the airport, then flew the airplane back. I drove the final leg home. What a day. Driving home, I couldn't help laughing at myself. I had taken an airplane solo some 300 miles; lost a navigation radio; bounced all over the sky; and become airsick, lost, and found again. I couldn't land at my destination field, was forced "on the fly" to divert, landed in a stiff and gusting crosswind, then had to drive the rest of the way home. Despite all this, I was planning my next flight and realized that I'd do it all over again. Here lies one of the great mysteries of flight.

John F. Campbell, AOPA 1149100, is a private pilot with more than 110 hours who is working on his instrument rating.