Stabilized is probably the most favored FAA concept. The stabilized approach technique is the sanctioned mitigation of the common land too fast problem. The stabilized approach employs static stabilization, the same airspeed all the way down. Deceleration seems not to come to mind, or is considered too dangerous. In cockpit resource management, stable, do one thing at a time, is touted. This is static. When Sully turned the APU on out of sequence on the engine out checklist, while making an energy management turn to the Hudson, that was dynamic thinking that saved lives in the back.

Areas of dynamic stabilization, like the law of the roller coaster and dynamic proactive rudder movement, get less attention. Yet the design of the airplane promotes dynamic stabilization. The airplane really wants to do it that way and is more effective (walking the rudder) and more efficient (energy management turn) doing it that way. Before instrument integration, flying was taught more dynamically. Using only reference to instruments, dynamic control movement had to be slowed down and limits to control movement had to be set.

Bracketing, dynamic proactive control movement, is employed effectively to control most any vehicle or machine in use. It is effective in rudder, elevator, and even throttle control movement. It is problematic in aileron control movement. Adverse yaw was something all the design engineers, save Fred Weick, could not eliminate. There is no dynamic proactive stabilization of aileron, save Ercoupe, in normal airplane design. Computer stabilized airplanes and helicopters are a different matter.

Awkward at first, dynamic proactive control movement is the cat's meow when practiced to proficiency. Nothing will get just right righter than rapidly alternating just a bit wrong each way. Historically, look at the bicycle or further back homo erectus. Progressively, look at bot. Listen to the servos when this guy is just standing still. We are innately stabilized with dynamic proactive muscle movement. As a young tennis player, I knew this. As a broken back and crushed leg rebuild old fart with nerve damage, I am up front and personal with the loss of dynamic proactive muscle control to stabilize human standing erectus. I walk a mile a day just fine. At the pharmacy, the chair for old guys is gone due to the pandemic. Walmart associates ask why the old man is taking a knee while waiting in line. Hover is a bitch now.

Dynamic elevator control is an effective energy management of RPM with fixed pitched props. Rather than go dynamic reactive with the throttle, which is energy inefficient, why not increase pitch just a bit when a gust spread increases relative wind, a positive shear, and pitch down just a bit when a gust spread decreases relative wind, a negative shear? So altitude becomes a bit dynamic. When a pipeline patrol student claims he is using throttle to both maintain RPM and strictly maintain the wavered 200' AGL altitude, I say there are no altitude police at this altitude.

If we use elevator rather than throttle to manually make our fixed pitch prop a constant speed prop, we are pitching up in updraft, positive shear, and pitching down in downdraft, negative shear. This may seem counter productive, altitude wise, but there will be a net gain in both altitude and groundspeed doing this because it is energy efficient both ways. In up air we want to go slower and stay in it longer for altitude gain. In down air we want to go faster to fly through it quicker for groundspeed gain.

So yes, over time we would get too high for good patrol reconnaissance. Energy management maneuvering on crooked pipelines and to occasionally return to target dampens this tendency. During normal A to B cruise, however, there will be a net gain in both altitude and groundspeed. Law of the roller coaster managed energy is like free energy.

Dihedral in the wing causes the bank of a turn to increase when we steepen with aileron to about 45 or more degrees bank. This requires the rudder to be necessary throughout steep energy management turns. In level turns we have to stop banking at some point to prevent load factor stall. In energy management turns, where we allow the nose to go down naturally, we allow the over banking and continue to use rudder in the direction of the turn. Not continuing to use rudder in the direction of the turn will result in slipping. Slipping reduces the rate of turn. Reducing the rate of turn in the low altitude energy management turn can cause a wing to still be down late in the turn to target, which is very dangerous. Reducing the rate of turn can delay getting around onto target before running out of altitude, which is very dangerous. We need to push the well down nose around, even chancing skidding. Skidding in the energy management turn is far less dangerous than stalling in a high g steep level turn at low altitude. High g level turns at insufficient altitude to recover from stall are the most dangerous turns.

Excellent posts Jim, thanks!

Keep ‘em coming Contact... Love that food for thought!

Thanks,

Tommy