I just finished reading "Fly by Wire" by William Langewiesche. While applauding Sully's miracle on the Hudson, he also praises the Airbus A320. I knew that the B-2s out of Whiteman AFB and the smaller Stealth Fighters I at Holloman AFB were shaped so differently that if the computers failed it was game over, bail out. I didn't know that the A320, which could otherwise fly like similar airline aircraft, had a computerized control system that made it as stall proof as the Ercoupe. Like the Ercoupe it would mush down many feet per minute without power. So we have got back all the way, airline wise, to the safety airplane William's father praised. Cars live in a much tougher environment, but we will soon have computer controlled cars as well.

But, many of us will still fly our favorite older airplanes with standard mechanical controls. Safety wise, we still have the elevator problem and rudder problem that Fred Weick engineered away mechanically so long ago in the Ercoupe. The elevator problem is that we overuse it to get up too quickly and to turn too quickly in the pattern where stall is fatal. Getting the low altitude orientation of airspeed is safety, not altitude is safety, is a hard sell. Lack of rudder, while not as apparently unsafe, becomes dangerous at low altitude where both vertical space and horizontal space are limited.

High altitude orientation, safety in altitude, can contribute to elevator misuse at low altitude where safety is in airspeed. Also contributing is the absolute need, even if it kills us, to maintain altitude in turns in the pattern and in other low altitude work. The designers of all out favorite older airplanes took care of that with dynamic neutral stability. If we allow the nose to go down naturally in turns, we are allowing this stability to function. The school solution so far, limiting bank, is high altitude orientation because it does not take into consideration limited horizontal space available. This limited bank sets up modern pilots for cognitive unavailability concerning rudder. Limited bank means a greater radius, arc, diameter of turn using up more horizontal space and making turns to target like the centerline extended impossible. Pilots with few iterations of steep turns and no iterations of allowing the nose to go down naturally, will eventually have trouble with limited horizontal space. This is especially true with a tailwind increasing the groudspeed and sending the radius, arc, and diameter of turn through the centerline extended or into terrain or obstructions.

Energy management, the law of the roller coaster, allows the speed oriented low altitude pilot to trade cruise airspeed for altitude and at the same time slow down to reduce the radius of turn. Getting around tighter and faster is useful to the low altitude pilot. In a steep turn, rudder in the direction of the bank will push the nose mostly down. This is good, not bad. This is safe, not dangerous. Yet, we have become cognitively unavailable to this fact. Steep turns cause load factor which causes stall? Yes, if muscle memory make us pull back on the stick in effort not to lose altitude. No, if we allow the nose to go down naturally. So now we come to limited vertical space, low altitude. With cruise airspeed, we had zoom reserve to gain enough altitude to turn very steeply for a limited time allowing the nose to go down trading that altitude for the important return to cruise airspeed. We have to analyse the amount of turn necessary to get onto target in the horizontal and vertical space available.

In crop dusting or patrolling pipeline at 200' AGL, Scott Perdue's "ground rush" will accompany the energy management turn. It doesn't cause the pilot to pull back on the stick to avoid the ground and stall. This should not be a problem at pattern altitude making 90 degree heading change (hopefully turns to target) turns. A 90 degree heading change takes very little zoom up and not a lot of bank. In the pattern it should be a turn to target, not a certain amount of zoom up and a certain amount of bank. As with any low altitude turn, it is best to overbank early in order not to be squeezed by downwind or events into banking more later in the turn.

The rudder is there for a purpose. It takes a lot of rudder to level the wing when too slow for the ailerons to be effective. It takes a lot of rudder to mitigate adverse yaw in the beginning of a steep turn and even more rudder to help get the nose down when the bank steepens.

So as Fred Weick designed the "safety airplane" to remove elevator and rudder problems last century, this century little people airplanes may have all around computerized stability soon. What I learned about the Airbus amazes me. In the interim, we who fly small airplanes in the pattern and at low altitude need to be cognitive of what the rudder is capable of doing for us in maneuvering flight.

Keep on preaching Jimmy . Thanks !

Glad you enjoyed the book. I was pretty anti-airbus until I read it. Why should the pilot be able to stall the airplane? Fred lives!

tbag,
The Airbus evidently smooths out a rapid pull up, like I was taught in crop dusting school. When teaching at Ag Flight, however, I met a young instructor who advocated a slower pull up started appropriately sooner. We don't want to leave crop untreated, but Dennis Nail had it right. We other instructors tried it, got good coverage, and didn't kill as much zoom reserve.
Same with the Ercoupe's limited elevator travel. You couldn't kill zoom reserve, but if you needed to go under the wires you also couldn't rudder turn around the poles.
Contact

My senility never fails to puzzle me. We have Ms.Pirate on here, an Airbus driver for Fed Ex. She could give us the full report on the airplane. Julie, can you elaborate on what William Langewiesche has to say about the airplane?

I have not had the opportunity to read this book, but I will do it on your suggestion!

I apologize to burst your bubble, but the Airbus I fly (A300-600), is one of the oldest still in service...
It still has a yoke, round dials, real wires to go to controls, and no HUD, no Sat phone.
So I can’t provide any insight on that subject.

Keep writing! I always enjoy your thoughts!

MS Pirate

It has been a long time since I worked with primary students, and now I am working with young instructors. It brings back memories. Young instructors are good, hard working, producers of the next generation of aviation. And they generally have poor cognitive availability of rudder. I don't know how to run a scientific survey, but I need data beyond my own experience with students and pilots in general. So please increase my awareness about rudder muscle memory vs. aileron muscle memory. In your experience will you, or your student, use as much rudder as aileron and will you or he/she move rudder as quickly as aileron in a strong gust upset that puts a wing down thirty degrees or more? And finally, how many of you will use rudder only, when slow, to bring the errant wing back up? I am looking for default muscle memory here. In an upset, which control is more available to pilots (cognitively or muscle memory) generally? Do we have a cognitive availability of rudder problem or is the teaching of coordination at maximum 30 degree bank getting it done? Do the lessons of the falling leaf maneuver translate to rudder only on short final?

Sunday I will address how lack of rudder movement, either by leading rudder or using rudder only, leads to loss of effective control in the pattern, on short final, and on the ground.