Backcountry Pilot • Primary control.

Primary control.

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Primary control.

A major misconception in training, where what is learned first becomes indoctrinated, is that aileron is the primary control. It is usually mentioned first, followed by rudder to control adverse yaw. The modern airplane can be driven much like an automobile using aileron only to 20 degrees of bank. This logically evolves as, "We use aileron to bank thus directing part of wing lift laterally, followed by rudder to mitigate adverse yaw. Given this execution of control movement, or pressure if you must, the nose will yaw opposite the bank initially.

Modern wing engineering, bungee interconnect, and Frise ailerons will hide the fact that the nose initially moves the wrong way. So we end up with weak teaching and poor performance. Nothing much comes of this misconception until upset or loss of control or the need to maneuver rapidly and effectively in the limited vertical and horizontal space of low altitude.

Airport operations, even at 1,000' AGL and 20 degrees of bank, are maneuvering flight at low altitude. Low enough to make stall/spin the leading fatality stastic in airport operations.

The simple solution to coordination problems is to teach "rudder pulls aileron " because that is how we turn properly. If rudder does not lead aileron just a bit, the nose moves the wrong way initially. If rudder does not lead aileron in a steep turn emergency at low altitude, fatalities often result. Even at altitude the initial wrong way nose movement causes basic instrument confusion and control problems. When was the last time you practiced Dutch rolls? If the nose didn't stay exactly on target, were you leading rudder?

Instructors, let's take students from where they are (turning with the yoke) to where they want to be. Before turns, teach level flight and how the rudder directs our nose to a distant target. Rudder control is primary. Adverse yaw is a bit more advanced. And if the instructors thinks aileron is necessary to hold a target and keep the wing level, he needs to put his hands in his lap same as the student. Crosswind? Not a problem. Use rudder only to direct butt to the target while keeping the wing level. We will side slip later on final.

Rob's method of teaching his son through solo with a towel over the instrument panel vaccinated his son from aviation low altitude fatality rate. He actually could see the nose move appropriately for the angle of bank. He could feel what the airplane wanted to do like pitching down naturally in all turns. He could hear the engine labor in it's natural dislike of climb and the relative wind fuss of too little rudder in turns. He could maneuver at whatever bank necessary to make a quarter mile wide pattern all around without ever hearing the stall horn or get sloppy, weak control feel. No numbers, no V speeds, no math is required for proper primary control of an airplane.
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Re: Primary control.

Good post Contact! Keep ‘em comin... Yes, 1,000 ft. is low altitude if you can’t recover from a stall from there.

Blue skies,

Tommy
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Re: Primary control.

+1.

Feet first. Keep your message coming Jim.

UpNorth
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Re: Primary control.

We instructors have all seen the student drive the airplane down the centerline with the yoke, Ercoupe style. But it's not an Ercoupe and the yoke is not connected to the nose gear. This seemingly innocent act, in a nose gear airplane, also becomes a major problem in a tailwheel airplane. Adverse yaw starts many a ground loop. That little bit of pull, way out on the end of a long wing, gets the piano (behind the mains) going off center.

And what's what with center, balance, the tendency of the nose to stay aligned with the direction of travel? It ain't. It is a myth. It doesn't naturally happen when we have the CG behind the mains. It continually wants to come around. We continually have to either dynamically proactively bracket the centerline or statically (just keep your feet still) and reactively (Oh! now jab) move the rudder. We have to flex the leg muscles to move the rudder. Why not get a head start. Just move your feet rapidly and alternatively each way. The brain will work out when just a bit more the one way or other way is needed. It cannot get there as quickly, from a flat footed start. Even if we have moved the wrong way, we are quickly going to go the other way. In fact we actually want to move the wrong way, and then quickly the other, assuming it really is lined up perfectly. It is not lined up perfectly, by the way. The physics of behind the mains CG doesn't allow that. Neither is in front of the mains CG, as in a trike. The difference is that the nose gear dampens the imbalance.

Finally the crux. The nose gear dampens the imbalance. Do we want to just stop here, instructors? Hell no! We want the damn feet to be moving dynamically and proactively here as well. Nose gear...just take the slack out of the nose gear to rudder pedal connection. Anti-torque pedals...just take the slack out of the pitch change links. Life is more dynamic proactive than we generally think. Ask your wife. We are going to always answer wrong. We need to just keep dynamically and proactively correcting. We need to keep moving our feet to stay ahead there too.
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Re: Primary control.

Amen Contact. Have a great Thanksgiving.

Best,

Tommy
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Re: Primary control.

Dang! I find myself once again looking for the "Like" button...
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Re: Primary control.

Thanks, guys. Concerning perfection, which no philosopher worth his words wants to see and end the quest, "If a man speaks in the Desert where no woman can hear, is he still wrong? We who have been married a long time certainly know the answer to that question.
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Re: Primary control.

contactflying wrote:"If a man speaks in the Desert where no woman can hear, is he still wrong?"

I asked my wife that question, and her answer was "Not only is he wrong, but you're wrong for even asking the question!" LOL
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Re: Primary control.

So, the title to this thread has nothing to do with keeping our airplanes in the air? [-X [-X

Happy Thanksgiving to All.
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Re: Primary control.

Sure it does. Happy wife, continue to fly.

Happy Thanksgiving
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Re: Primary control.

My understanding of rudder rather than aileron as a primary control came from stall and slow flight practice at altitude, Dutch rolls to 45 degree bank, deceleration on short final to touchdown on the numbers slowly and softly, and Bruce Washtock's presentation at Grande Prairie Alberta.

In the Rudder travel thread presently up, Brian of Brian Steves Aircraft explains a directional stability test that proves the concept. With lots of power and high pitch attitude, the airplane fails if aileron without rudder causes too much roll. So if roll is not desired there, must not the design stability of the airplane be that vertical stabilizer and dorsal fin stabilize roll. In this powered but slow flight, as in a good power pitch deceleration from short final to touchdown on the numbers slowly and softly, what if we want to correct alignment with the centerline extended? You gotta love that rudder.
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Re: Primary control.

You are getting forgetful Jim. Its Butch not Bruce... everything else is good.
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Re: Primary control.

Ah, David. So hard to fool one who has witnessed my senility in the flesh.
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Re: Primary control.

Does muscle memory cancel muscle memory. Does the muscle memory of aileron first and then rudder, what is called coordination or balance, cancel the muscle memory of rudder leads aileron or rudder as a primary control? I don't know. If we just lead rudder a bit, in our coordination, and continue to use rudder beyond 45 degrees of bank where rudder helps get the nose down, we will be OK with dynamic proactive rudder only on takeoff, short final, landing, and roll out. Yes we use the aileron to bank the wing into any crosswind as necessary, but that doesn't mess with our minds like no crosswind or a gentle crosswind. Here we may think there is no wind and we can just steering wheel the airplane down in a very coordinated way.

Rudder is primary. If we move the controls, we move rudder or have problems. Aileron is not primary. If we move the controls, we may or may not move aileron. Move the throttle. A little rudder will be required. Move the elevator. A little rudder will be required. Miss that tree.
A lot of rudder may be required. Move the aileron. Too late, rudder should have led.

If rudder is going to be primary in our iterations, rudder must be always on our mind. Rudder must be primary.
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Re: Primary control.

“ Rudder is primary. If we move the controls, we move rudder or have problems. Aileron is not primary. If we move the controls, we may or may not move aileron. Move the throttle. A little rudder will be required. Move the elevator. A little rudder will be required. Miss that tree. A lot of rudder may be required. Move the aileron. Too late, rudder should have led.

If rudder is going to be primary in our iterations, rudder must be always on our mind. Rudder must be primary.”

You need to get this in ‘mantra’ form; so we can chew and chant on it...

Blue skies,

Tommy
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Re: Primary control.

"Om," is more soothing, but I always just said, "walk the rudder," repeatedly. Dynamically and proactively working the yoke is common and disruptive. Rudder, not so much. Meybe if I just sat there saying "0mmmmm."
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Re: Primary control.

The uncoordinated turn or roll caused by moving the heading selector on the wing leveler or flight director was way too sloppy for bombing, so the bombadeer simply used his own rudder trim. The same can be done directing our nose between our legs or our butt in a crosswind toward a distant target. For hand flying by instrument, the line or half line on the DG can be bracketed by walking the rudder. This helps a lot in rough air so wing wagging, using coordinated turns to react to gust spread, doesn't get started making the ride even rougher.

Contact flying to patrol a pipeline or follow a river can be a wild ride using coordinated turns, and a wing can get too close to things, but rudder only to direct our nose between our legs or our butt in a crosswind toward the pipeline or river up ahead is much more smooth and safe. When the change in direction of the pipeline or river is to great for a rudder turn, an energy management turn using cruise airspeed to gain a bit of altitude in a zoom and slow down to reduce the radius of the turn and allowing the nose go down in the turn is more efficient, easier on the stomach, and much safer than a high g level turn. Rudder is used against P factor in the zoom and then to start the turn in the correct direction and through and beyond 45 degrees of bank, to help get the nose down and to keep the nose moving appropriate to the increased bank. In steep bank, the nose should be moving briskly across the terrain below. This requires lots of continuous rudder.

So in maneuvering flight, where aircraft maneuvering needs to be very precise, the rudder is indeed primary. The most dangerous error, in maneuvering flight, is insufficient rudder usage in the direction of the turn. The resultant slipping turn of slower than optimum rate causes wing low in the bottom of the energy management turn and delay in getting the nose around and onto target so we may level the wing prior to overflying the target and pulling up out of the dive resulting from the nose going down naturally.
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Re: Primary control.

The energy management turn, while very natural, has a very active pilot as well. Pitching up in the zoom, we are walking the rudder a bit to keep the wings level. This walking becomes a bit grosser as airspeed decelerates. Now very slow, in the top of the zoom, we start the turn in the desired direction with lots of rudder in that direction. We are slow requiring gross rudder as well as gross aileron. Once the nose has started in the correct direction, we apply lots of aileron to dial in more bank early in the turn so less may be required late in the turn. This extra aileron (we're slow here) needs extra rudder besides the rudder to start the turn, to increase the rate of turn early in the turn. In maneuvering flight we are working with limited horizontal and vertical space. Even in shallow turns, we don''t want a slip to decrease the rate of turn and delay the turn getting onto target at the proper speed for the angle of bank. In the bottom of the dive that results naturally form rudder application and aileron application, we again want to level the wing quickly to pull up wings level over the target. This requires rudder application first in the wings level direction followed by aileron to level the wing. Again, the rudder gets the nose continuing toward or stabilized onto the target. And in shallow turns, where the nose has not gone down significantly, we are a bit slower still requiring grosser rudder.

All this seems counter-intuitive for the well coordinated pilot. Not so. The well coordinated pilot is already doing this. He nails the target in shallow as well as 45 degree bank Dutch rolls. Dutch rolls will always evaluate the amount of rudder the pilot is using, or not using, prior to aileron in the direction of bank. Too little rudder, very common, results in a pause which destroys the symmetry of the maneuver. Too much rudder, very uncommon, results in a skid that throws the nose ahead of the turn.

Finally, the good stable pilot does not have to use the rudder as aggressively as I have described in this thread...so long as he limits his control movements to the speed and extent necessary to remain stable in flight by reference to instrument indications only (IMC.) Integrated instrument flight, the school solution, requires only control movement to the speed and extent necessary to remain stable in flight by reference to instrument indications. Given instrument meteorological conditions, this is the very safest way to fly. Given visual meteorological conditions, with uncontrolled aircraft and uncontrolled airspeed and uncontrolled altitude and uncontrolled procedural track, maneuvering flight may be the safer way to fly.
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Thanks again Jim

Keep ‘em coming !
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Re: Primary control.

It is important, in energy management turning, to orient on the target rather than the horizon. The small amount of contact flying training required for the Commercial Pilot Licence emphasizes a faster rate of turn using elevator to increase Gs in steeper banked turns with horizontal orientation. To increase rate of turn, elevator along with aileron now becomes primary in the students mind. As with PPL training, this one plane orientation still requires load factor consideration and bank limitation to be safe. Sort of a rock and a hard place problem. We are being taught to tighten up a bit by using more back pressure on the elevator and more bank, but we are not to lose control. Yet, greater bank while increasing pitch to maintain altitude and increase rate of turn increases the likelihood of loss of control through stall.

Again, it is critical in energy management turning and in safe maneuvering flight to orient on the target rather than the horizon. Employing the law of the roller coaster to manage energy to bring the nose up, around, and down onto the target is much safer than sucking the nose around the horizon at very high G loading on the wing.

Neither dog fighting nor safe maneuvering flight is limited to the horizontal plane. Yes, the fearful mind increasingly wants to maintain altitude as we get closer to the ground. Altitude has been touted as the only safe condition. Only by increasing our world view vertically as well as horizontally can we truely fly safely at low altitude. Only by giving rudder its primary position among the flight controls can we truely fly safely at low altitude. Only by using vertical as well as horizontal space available can we truely fly safely at low altitude.
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