Share this story
In the days before the advent of the Boeing 757 and Airbus A320, with their glass cockpits, full-featured autopilots, and autothrottles, most airline pilots would fly their aircraft by hand from takeoff until reaching the flight levels and then all the way back down again. Even though these were big and complex systems, they could do it with remarkable precision. How? They had a deep understanding of their configuration settings.
A few years ago, a dear friend and experienced former B-52 instructor returned to the cockpit after a four-year absence while he was engaged in desk duties. During his very first takeoff, flap retraction, and climb to FL 310, the airspeed never deviated by more than 5 knots either way, the altitude was within 25 feet of the mark, and the heading was spot on. The same was true for the descent, approach, and landing.
Now, the “BUFF” isn’t the easiest aircraft to fly precisely due to its design from the 1940s, its quadricycle landing gear, and its huge fowler flaps. Watching this demonstration of aviation precision, the young copilot wondered if this accuracy was due to the pilot’s “experience.” The pilot replied, “Perhaps a bit, but more likely because the night before I calculated each pitch, power, and trim change needed to fly the airplane precisely.” You see, airplanes don’t know whether the pilot has experience or not, but each aircraft is acutely aware of the laws of aerodynamics and physics.
So, which is more important, establishing the correct pitch, power settings, and trim, or responding to the altimeter, airspeed, and heading indications? Thanks to the works of Mr. Jacob Bernoulli, Sir Isaac Newton, George Cayley, and, of course, Mr. Charles Taylor, who gave practical aircraft propulsion its start, our aircraft follow a set of clearly defined rules. Their efforts have created aircraft that comply with the laws of physics and are balanced in flight due to the precise setting of pitch, power, and configurations. The flight instruments are simply, to borrow a term from economics and business, a “lagging indicator” of where the aircraft is or has just been. Adding in the additional time it takes the average busy pilot to see and process the indications on the panel while performing numerous other required tasks, and the term “chasing the gauges” becomes easier to comprehend.
Back to the B-52. As it turned out, there were only a couple of power settings that were worth remembering. Takeoff and climb power are calculated from the flight manual. Then, amazingly, a single total fuel flow value of a bit less than 20,000 pounds of total fuel flow per hour allowed the aircraft to either cruise at altitude in a clean configuration, fly downwind in the pattern with the flaps in the down position, or fly a 3-degree ILS final approach with both the flaps down and the landing gear extended.
And each configuration change required a specific trim change value. The landing gear was worth one trim unit, the flaps three-and-a-half units, and the airbrakes another unit or so. So as the aircraft was changing configuration, this pilot simultaneously adjusted the appropriate power and trim settings. Remember back to the days when you were a student pilot and the flight instructor covered up the airspeed indication to allow you to land without it. The usual, counterintuitive result was that airspeed control immediately improved.
In our modest general aviation contraptions, power is usually set by RPM (for fixed-pitch prop power systems) or manifold pressure (when there’s a constant-speed prop). The settings are usually given for takeoff/climb power, cruise, and traffic pattern/descent/approach settings. The flaps and retractable landing gear each have their own specific trim requirement, which varies from aircraft to aircraft.
So why wait to see what happens? As the aircraft slows and configures, we can simultaneously set the appropriate pitch, power, and trim settings. Many of our aircraft require a modest power increase and trim change as the last 10 degrees of flaps are deployed. Anticipating this change (increasing power while decelerating) with an appropriate power increase and trim response enables the aircraft to stop its deceleration and find the “sweet spot” on the ILS or visual final. Once the pitch, power, and trim are set, check the instruments, and they will likely show that you are on course, on the glide slope, and at the correct speed. For VFR flying, this means more time to look outside the cockpit! For IFR, it means fewer distractions and more time spent on navigation and communication.
We human pilots have our work cut out for us. Autopilots don’t have to search for traffic, talk on the radio, answer questions from passengers (“are we there yet?”), or decide if the weather is suitable for landing. Those of us flying single pilot, IFR, in a legacy aircraft have to do all that and more. We’ve got our work cut out for us.
So, what should we do? Help your airplane fly the way it wants to. Think about the most frequently used pitch/power/configuration combinations and simplify the task at hand. Anticipate the required settings for each situation or configuration and be confident that when you check the gauges, the cockpit indications will be what you expect.
Concentrate on fewer and more precise throttle and control inputs rather than a large number of more reactive ones. If the gauges and the windscreen picture don’t match, reevaluate your inputs. Remember, every time we make a control input, our aircraft will check with the usual suspects (Bernoulli, good old Sir Isaac, Cayley, and Mr. Taylor) to ensure it follows all the rules. You can make your flying more efficient and precise by making your plane’s job easier. PP
___
Frank Ayers has been flying for over 45 years. He is an experienced military instructor pilot with over 4,000 hours in the Boeing B-52 and holds both ATP/B757/767 and CFI certificates with over 2,300 additional hours in a wide variety of general aviation aircraft. He enjoys teaching young people about the art and science of aviation and flight safety at Embry-Riddle Aeronautical University.
