A Continuous Near-Miss

A huge formation of Beech T-34 trainer warbirds thunders over the EAA International Fly-In Convention at Oshkosh, Wisconsin, every year, landing lights blazing and airshow smoke flowing. Formation flying looks so easy, you think.

As it turns out, looks are deceiving. Think of formation flying as a continuous midair threat and you will understand the problem. Let's put you in the front of a 285- horsepower T-34 (similar to a Bonanza, but with tandem seats) at Texas Air Aces for a training flight. Your flight is part of a $1,500, five-hour introductory wingman course. (It takes 10 hours to become a good wingman — to know that you can stick with the leader no matter what — and longer still to become a flight leader.) With 10 hours of training you'll probably be skilled enough to earn the T-34 Association's wingman patch required to fly in that huge Oshkosh formation. But first things first.

You're in position on the runway at David Wayne Hooks Memorial Airport, 28 miles northwest of Houston. You've studied the T-34 Association's Formation Flight Manual thoroughly (a good general overview, no matter what type of aircraft you fly), so you have an idea of what to expect in a formation takeoff. It has even been demonstrated on a prior flight. There was also a thorough preflight briefing; without that, you don't fly formation. And you have taken the time to learn the skill levels of the other pilots in the formation. If you don't know them, you don't fly. The backseater is former Air Force fighter pilot Tom Delashaw (call sign: "Sharkbait"), an instructor especially skilled in keeping students from having midairs.

Slightly ahead and on the downwind side of the runway (so that the leader's turbulence will blow away from you) sits another T-34 with Texas Air Aces President Don "Phantom" Wylie, a decorated Air Force combat pilot, in the back seat; your fellow student is in the front seat.

Unfortunately, like most who are new to formation flying, you have a few misconceptions that must be shed in these seconds before takeoff. You normally make the decisions at work, in your personal life, and most certainly when you fly. Well, not this time. This time, you will go where the leader wants when he wants and do what he wants to do. The leader is your world.

The leader raises his arm and makes a circular motion with one finger. You interpret the message: Bring up the power. The lead pilot taps the top of his head. Watch me. Now he leans his head back and brings it briskly forward. Release brakes. The throttle is a paddle-shaped lever on the left side of the cockpit, like that in a jet fighter. From the start of the takeoff roll, it is clear that formation flying requires brisk throttle movements — something you normally avoid if you respect the engine. Full power brings you almost ahead of the leader; so reduce power. (Positioning the aircraft side by side assures that if the leader blows a tire and veers toward you, he will slow and cross behind you.) Now you're back in position and accelerating — back to full power. You call on the radio, "Lead, give me two," and the leader reduces the throttle by two inches of manifold pressure to give you a power advantage. Watch his landing gear struts; when they decompress, add back stick pressure. But you fail to notice it. Okay, watch for the leader's nosewheel to come up; now, add back pressure to match.

You're above the runway, flying insanely close to the other aircraft, it seems. That's a good position. Almost level with the leader at this point, but far enough away that the wing tips will clear should you goof and surge ahead. The leader's arm is in motion, as though thumbing for a ride. Gear up. You fumble for the gear switch, afraid to look down for it. The leader's head tilts back and snaps forward. Raise the gear now. A minute later the leader is motioning with the open palm of his hand, as though pulling something toward him. Reduce power. Frenetic little devil, this leader. Doesn't he know how busy you are?

You're airborne and cleaned up. A stolen glance ahead tells you that the trees and all man-made objects are well below. Time to drop into formation position, which for the T-34 is 45 degrees behind the leader and down. How far down? Position the aircraft so that the last engine cowling latch on the leader's aircraft appears to be right above the gap between the leader's flap and aileron. This is precise stuff. Even in this position, the wing tips will clear if you accidentally rise and race forward. By the same token, if the leader slows and descends suddenly — as could happen when returning to the airport — you'll have room enough to get out of the way.

Since the aircraft is cleaned up, you think about retrimming, but you're just too busy. Then there is a nudge on the stick, or so you think, and you mistake it for a silent command from the instructor that he wants control of the aircraft. So you let go. Up and up the aircraft floats, like an elevator, until you are out of formation. Delashaw inquires bluntly as to your intentions and returns the aircraft to position. He reminds you that if he wants the aircraft, he will not only shake the stick, he will say so. The incident brings to mind a somewhat similar error that kills many an experienced formation pilot. Who has the lead? Sometimes that is the last question heard over the radio before the impact, experienced formation pilots say.

To reinforce the lesson about trim, Delashaw takes control of the aircraft, trims it, and asks you to look at him in the rearview mirror. The T-34 is flying perfect formation — his hands are off the controls.

Sun glints off the leader's aircraft. Where's that latch? Never mind. There are large numbers painted above the latch. So put the numbers above the flap/aileron gap. Concentration is so intense that you see only the bottom half of the numbers. (In my case, I insisted to Delashaw after the flight that I had kept the number "101" above the flap/aileron gap. It was actually "01.") Now the leader's T-34 is backlit against the sun and even the flap/aileron gap becomes difficult to see, but there is an Air Force star on the underside of the wing, near the gap. Use the left side of the star.

Presently the mixture of blue sky and green land in your peripheral vision changes to all blue, then all green. You don't know why and don't care; you're fighting to keep the numbers over that star. Later, you will discover that Wylie has asked your fellow student in the lead aircraft to give you a workout and perform lazy eight maneuvers that aren't so lazy. You're concentrating fiercely. Throttle forward to catch up. There, now back again. You've got to reduce power early to avoid drifting ahead of the leader. You're getting too close to the leader — no wingtip separation, and too little vertical separation! Bank right. Push the stick forward. How long can this go on?

Twenty minutes later it's time to take a break and move into lead position. Now your job is to fly as smoothly as possible and always to be aware of your wingman. Do you fly with your head down in the cockpit too much? You've got to break that habit now and frequently look at the wingman — that parasite that seems chained to your aircraft. (In fact, one foreign formation airshow team flies aerobatics while literally chained together.)

Circle one finger above your head. No, it doesn't mean power up. You did that on the runway. Now it means "Break." It is time for the other pilot to practice rejoining the formation, but first the formation must break apart. Roll away from the wingman sharply a mile or so, then enter a 30-degree bank, as briefed, toward the wingman. It is his job to cut off your turn by constantly pointing the nose of his aircraft ahead of your aircraft.

And here he comes, like a heat-seeking missile with you as the target. He's forgotten to keep blue sky below your aircraft during the early phase of rejoining and at this moment appears intent on spearing you. The closure rate is too fast, but at least his instructor is now making him stay below you. To teach him a lesson, your instructor orders you to wait until he is closer, then steepen the bank toward the wingman. The resulting increase in an already fast closure rate startles the wingman, who is now 200 feet below you.

He tries to stop on your right side, where he belongs, by banking farther and farther away from the lead aircraft, like cartoon character Wile E. Coyote digging in his heels to stop. It is a common student error, and the worst: going belly up to the leader. The wingman has lost visual contact with the leader and, had he not stayed below you, could have drifted into you. The wingman's instructor tells him to reduce the bank, allowing his aircraft to shoot under the leader; now it is safe to bank and stop on the left side. Once under control, he crosses back under the leader and moves up the 45-degree line into position on the right side.

"Two's in," the wingman calls on the radio. That's your name, too, when flying wing. You're reduced to a number. During the preflight briefing, your leader asked you to be quiet on the radio when in formation. He's busier than you are, if you can believe that — navigating, looking for other aircraft, watching you, talking to the tower, and operating his radios. "I don't want to hear anything from you except 'Two's in' and 'Lead, you're on fire,'" the leader said. When the leader gives instructions on the radio, you acknowledge with a simple, "Two."

Turns are next. If the leader banks away and you wish to stay on his 45-degree line, you must climb as much as 50 feet. If the leader turns into you, you'll have to descend 50 feet. But in the pattern, close to the ground, you may not want to descend. So you will do an echelon turn. When the leader banks, you bank, making no attempt to climb or descend to stay on the leader's 45-degree line. It gives the wingman the uncomfortable feeling of being directly beneath the leader. Try to keep the leader's propeller spinner on the horizon. When the formation rolls out of the turn, you should discover that you are once again on the 45-degree line.

Now it is time for real-world training. Your instructor suggests that you lie to the wingman, telling him that the next turn will be toward him. Now wait two seconds — and here's the sneaky part — bank away from the wingman briskly. The student wingman, of course, goes out of position. Some day you may fly with an inexperienced leader — or even an experienced one — who gets confused and goes right when he meant to go left. Today's lesson is to remind the student to maintain that fierce concentration.

Finally it is time for you to return to the wingman position again — that never- ending work load — to learn something called the crossunder. But unknown to you, Delashaw has been concerned that his smooth-flying aircraft is out of rig. Since the flight began, the rudder coordination ball has been out of center. Unintentionally, while on the leader's right side, you've been pushing the right rudder to escape to safety. Don't be embarrassed — it happened to me, too. Three-fourths of me wanted to fly formation, but the right leg did not. The only solution was to fly with both feet flat on the floor. Like misbehaving children, my feet had been told to go sit in a corner, and it worked. Sometimes, in the heat of concentration, that right foot would slip back to the rudder pedal and try to take the aircraft away from the leader. Delashaw had to check on me every 10 minutes.

"Are ya feet on the floor, Al?" Delashaw would ask in his slow Texas drawl. When the reply was, "Nope," Delashaw would follow up with a second question.

"Are they now, Al?"

"Yup."

"Ball's in the center, Al," Delashaw would note.

(Texas Air Aces videotapes every flight from cameras inside and outside the aircraft for its customers. That "feet on the floor" conversation above is repeated on several of the tapes.)

But enough about me. You're the one flying this thing, and there are crossunders to learn. When returning to the airport for a formation landing, the leader must position the wingman to the outside of turns in the pattern for safety. There's the signal, a stationary clenched fist. Cross under.

Back off the power and move backward and down along the 45-degree line from the leader. This assures not only good propeller-to-tail clearance in preparation for passing under the leader, but it also puts the wingman beneath the leader's propeller turbulence. Think of dancing a box step behind the leader. Move outward and down to the first corner of the imaginary box, then add power to stay in position as you tilt the wings very slightly, and cross under slowly to the second corner off the leader's opposite side. Now add more power to move forward and up the imaginary 45-degree line. Common mistakes include using too much or too little power and fumbling for the correct position, but you have an experienced instructor in the back and several hours of practice to get it right. You'll need both.

Now you've crossed under and are on the proper side for pattern entry. It's time for your first formation landing. It has been demonstrated to you on a previous flight. Two airplanes' landing on the same runway side by side goes against all your training; but, once again, the key is to concentrate on the leader. Delashaw, in the back, moves his hand within an inch of the stick and partially curls his fingers. It will take less than a second for him to assume control, should that be needed.

As was the case just after takeoff, you have moved up level with the leader and slightly forward of the 45-degree line. The leader motions thumbs down. Gear. Get your hand on the gear lever, but don't look down for it. Then a head nod. Lower the gear now. The leader has just noticed that the formation needs to lose much more altitude. Forgetting the wingman, he makes a huge power reduction. You shoot ahead of the leader; thank goodness, there was vertical and lateral separation or this would have been a midair.

Now he's moving his fingers as though making a hand puppet of a quacking duck. Flaps. And another head nod. Lower flaps now. You and the leader exchange thumbs up. Your gear's okay. On short final you are allowed a peek at the runway to assure that you are lined up properly. And, if you are a rudder abuser, you may now put those feet back on the pedals. The leader will land on the downwind side so that his turbulence will not drift into you. That may require another crossunder, which is one reason why formation pilots like long final approaches.

One hundred feet. The peeks at the runway are becoming more frequent, but not so frequent that you stop concentrating on the leader. Look at the runway. Now the leader. Back to the runway. There's too much to do. Fifty feet, and your brain's master caution alarm goes off, indicating overload. Your natural aversion to landing this close to another aircraft kicks in. The adrenaline is flowing. Stay level. Stay lined up.

In the flare now. Put the eyes on quick scan: leader, runway, leader. Let's make it look good, with wheels of both aircraft on at the same time. Whoops! Your wheels are on, with the leader still two feet in the air. You blew it. Maybe next time. Now he's down. Taxi to the ramp one plane length behind the leader. Just because you are on the ground is no reason to look sloppy. A sloppy flight is derisively called a gaggle. You don't want to be a gaggle.

Both Wylie and Delashaw make a point of congratulating their students as they emerge victorious from the cockpit, because they know the tail camera will capture it on videotape. And out comes Ellie Guadagnola of the Texas Air Aces staff with hot towels and a cup of water to welcome the heroes. You've learned a new skill, one that contributes to making you a disciplined, safe pilot, even if you'll do little formation flying. And you feel like an ace, a Texas Air Ace, to be exact.

To order your copy of the T-34 Association's Formation Flight Manual , send $5.50 plus $3.25 shipping to Dave Holt, 2225 N.E. Highway 20, Bend, Oregon 97701. It was written by Lou Drendel, Jim Nogle, and Bob Farrell of the T-34 Association, and blends the best of techniques from the Air Force, Navy, and civilian worlds. For an excellent ground school in formation flying, get the two-volume videotape titled Formation Flying: The Art , available from Sporty's Pilot Shop for $69.95 plus shipping. Call 800/SPORTYS. To contact Texas Air Aces, call 713/379-ACES.

The Flyby

Strap in and start thinking

11:50 a.m. — You enter the ground effect at just under 300 mph, two feet from the leader's wing tip, in a 70-degree bank. So far so good. Then you notice the bank beginning to increase. You're ready for it, and it changes only a degree or so, but it takes that much to notice. It's a smooth increase — definitely the lead's doing and not that of the turbulence. But whatever the reason, right now you've got to play catch-up. The sooner you can "catch" his bank angle, the better you'll be able to stay with him as he continues to increase his bank.

So you press the aileron toward the lead to increase the bank. Because the bank is increasing and the altitude (hopefully) is remaining constant, the G is increasing, which means not only has the stick force changed, but the angle of attack has, as well. The increased angle of attack produces a change in p-factor, for which the rudder must compensate.

The increased angle of attack also changes the induced drag that must be compensated for, only this time with the power. Of course, the increased power changes several things, as well. First, because the pitch of the propeller changes to maintain the selected rpm, both torque and p-factor change. The rudder is used to correct for the p-factor, as before; but it, in turn, produces a rolling moment because of the vertical center of gravity difference and dihedral effect — and the ailerons must compensate, subsequently changing the stable position of the ailerons and requiring further changes in the rudder.

This circular sort of rudder/aileron interaction continues in ever-decreasing magnitudes until the next major change occurs — or more probably while the next major change takes place. Superimposed over all this is the torque effect caused by the increased blade angle on the now-greater engine output. So not only is the aileron used to compensate for the rudder input, but simultaneously it is used to counter the effect of increased torque.

Not to be forgotten is gyroscopic precession. Any movement around the lateral axis causes a coupling in yaw, which must be allowed for. The movement in pitch, because of the increased G, sets this off; rudder must again be used to compensate. In turn, the rudder does its dirty deed of creating a rolling moment because of vertical center of gravity and must be compensated as before.

Further, because of the increased angle of attack on both aircraft, the downwash off the lead's airplane requires an increased angle of attack on the wingman's aircraft. So in addition to everything else, the increased angle of attack because of downwash must be compensated for. Remember also that the downwash increase is taking place linearly but continuously and must be allowed for to a differing degree as the bank is increased. This requires a power addition for the increased drag of higher angle of attack which, as before, produces a change in torque, p-factor, and gyroscopic precession, as well as slipstream effect. So, as before, rudder, aileron, and power must work to correct the major defect; then, in turn, each must work to dampen the coupling effects each of them has on the others' movements.

Because of the increased bank, the Gs have pushed you farther into the seat, requiring compensation for the new visual picture. Even though the airplane hasn't moved, it is up to you to determine just what this new picture needs to look like in order for the two airplanes' positions not to change relative to each other.

Now, assuming you overshot once high and once low and then again only slightly high and again slightly low in trying to capture the roll rate/angle, that's five corrections starting to roll and similarly five corrections stopping the roll. That's 10. Now, for each one of them, you have the corrections for adverse yaw produced. Let's say, for argument's sake, that you catch the correction with just one overshoot, then nail it. That brings the total corrections to 20; and so far we've dealt with only the roll versus adverse yaw aspect of the flyby. Because each rudder input to correct for adverse yaw also produces its own rolling moment, an overshoot/undershoot correction must be applied to each of the 20-so-far corrections, bringing the total to 100.

Next, the power corrections: Power must be added because of the increased angle of attack, Gs, and turn radius. Assuming an average of five tries to narrow the power to match that required and an associated "overshoot/undershoot/little overshoot/little undershoot/right on" series to nail down the rudder required for p- factor, that's 25 corrections — bringing the grand total so far to 125.

Next is the rolling moment caused by vertical CG corrections and dihedral effect that — because they happen concurrently with the adverse yaw corrections — produce a series of five corrections for each of the 100 already demanded for adverse yaw, bringing the total to 625. The five power corrections also demand another five-series correction for torque which, because they couple to affect the rudder and its associated 125 corrections already discussed, bring the total to 15,625 corrections.

If you include the changing downwash as it affects each wing, then you have to address the associated aileron/rudder/roll caused by CG/p-factor corrections as they affect each of the corrections so far; that is 15,625 x 15,625 — or more than 244 million corrections.

It is still 11:50 a.m. Elapsed time so far, three-quarters of a second. No wonder you sweat. — Carl Pascarell

Know When to Say When

How things can go wrong during a formation flight

Like many pilots, I had engaged in so-called "formation" flights before getting any official formation training. I didn't jump into engaging in formation flying completely unprepared, though. I had received a lot of good tips from a qualified friend some years back while he maneuvered my airplane into position for a professional video. On that flight I learned a lot about picking reference points, crossunders, and especially how constant throttle adjustment was necessary to maintain position. But what I didn't realize then was how fast things can go wrong in a formation flight.

Because our work sometimes involves flight for photographic purposes, fellow Associate Editor Al Marsh and I were sent to Texas Air Aces to get a real-world look at flying close formation. We did pretty well at maintaining position during some rough turbulence and light maneuvering, but the real lessons came when distractions were suddenly thrust upon us.

Al was leading one particular training flight, while I was flying wing stacked down. At one point while I was on his left wing, Al spotted traffic that would surely require him to make a left course change. Like a good leader, he was aware that I was on his left and he did not want to make any sudden moves in my direction. Over the radio came the voice of Al's instructor, "Give me a little room here, guys," as he took control of the lead airplane from Al and began a left correction. The course correction was too fast for my newly minted formation skills and the lead began to cut me off as he entered a descending left turn. My correction was too late to maintain vertical clearance by descending, so I elected to climb while turning left. I helplessly watched as my leader fell mostly out of view under my right wing. My instructor, who was looking for the traffic in the second that these events unfolded, realized that his usually good student had gotten the flight into a precarious position. From his point of view in the T-34's aft cockpit, he was unable to see the leader at all.

"I got it," he said as the stick was wrenched from my hand. We canopy-rolled upward to regain the view of our leader, and within seconds we were thankfully back into a position where I could regain composure. As for the traffic — who knows where it went during that few-seconds scare? All I knew is that I was glad that I had an experienced formation pilot to bail me out of a bad situation.

Since that incident, I have given formation flight new respect and have seen the creation of potential disasters — especially when a camera is introduced into the situation. Recently, a network camera crew from Canada wanted to take in-flight photos of aircraft involved in an air race. As expected, volunteers came from all directions. One in particular, who was claiming worlds of knowledge about formation flying, wanted to put seven dissimilar aircraft (most of whose crews had never flown formation) up there at once. At that point, I knew that this was something I wanted no part of. Even the camera crew shied away from the scene.

As pilots we are all taught to gauge a situation and make a decision based upon available information. When the adrenalin-fed excitement of a formation flight begins to overcome sensible judgment, pilots must know when to say when. — Peter A. Bedell