The ability to sense a flight condition, such as straight- and-level flight or a dive, without relying on cockpit  instrumentation is often called “feeling the airplane.”  Examples of this “feel” may be sounds of the airflow across  the airframe, vibrations felt through the controls, engine and  propeller sounds and vibrations at various flight attitudes, and  the sensations felt by the pilot through physical accelerations. Humans sense “feel” through kinesthesis (the ability to sense  movement through the body) and proprioception (unconscious  perception of movement and spatial orientation). These  stimuli are detected by nerves and by the semicircular canals  of the inner ear. When properly developed, kinesthesis can  provide the pilot with critical information about changes in  the airplane’s direction and speed of motion; however, there  are limits in kinesthetic sense and when relied upon solely  without visual information, as when flying in instrument  meteorological conditions (IMC), ultimately leads to  disorientation and loss of aircraft control. Developing this “feel” takes time and exposure in a particular  airplane and only comes with dedicated practice at the various  flight conditions so that a pilot’s senses are trained by the  sounds, vibrations, and forces produced by the airplane. The  following are some important examples: A flight instructor should direct the beginner pilot to be aware  of these senses and teach an awareness of their meaning and  their relationship to the various conditions of flight. To do  this effectively, the flight instructor must fully understand  the difference between perceiving and reacting to sound,  vibrations, and forces versus merely noticing them. A pilot  who develops a “feel” for the airplane early in flight training is  likely to have less difficulty advancing in their flight training. Sources of actual “feel” are very important to the pilot. This  actual feel is the result of acceleration, which is simply how  fast velocity is changing. Acceleration describes the rate of  change in both the magnitude and the direction of velocity.  These accelerations impart forces on the airplane and its  occupants during flight. The pilot can sense these forces  through pressures into or out of the seat; or shift the pilot from  side to side in their seat as the airplane slips or skids. These  forces need not be strong, only perceptible by the pilot to be  useful. An accomplished pilot who has excellent “feel” for  the airplane is able to detect even the smallest accelerations. An airplane’s attitude is determined by the angular difference  between a specific airplane’s axis and the natural horizon. A  false horizon can occur when the natural horizon is obscured  or not readily apparent. This is an important concept because  it requires the pilot to develop a pictorial sense of this natural  horizon. Pitch attitude is the angle formed between the  airplane’s longitudinal axis, which extends from the nose  to the tail of the airplane, and the natural horizon. Bank  attitude is the angle formed by the airplane’s lateral axis,  which extends from wingtip to wingtip, and the natural  horizon.  [Figures 3-3A  and  3-3B]  Angular difference about  Figure 3-3.  (A) Pitch attitude is the angle formed between the airplane’s longitudinal axis. (B) Bank attitude is the angle formed by the  airplane’s lateral axis. 3-4 • Rushing air past a cockpit creates a distinctive noise  pattern and as the level of sound increases, it likely  indicates that the airplane’s airspeed is increasing  and that the pitch attitude is decreasing. As the  noise decreases, the airplane’s pitch attitude is likely  increasing and its airspeed decreasing. • The sound of the engine in cruise flight is different  from that in a climb and different again when in a  dive. In fixed-pitch propeller airplanes, when the  airplane’s pitch attitude increases, the engine sound  decreases and as pitch attitude decreases, the engine  noise increases.  • In a banked turn, the pilot is forced downward into  the seat due to the resultant load factor. The increased  G force of a turn feels the same as the pull up from  a dive, and the decreased G force from leveling out  feels the same as lowering the nose out of a climb. Attitude Flying Feel of the Airplane Pitch Roll A B Angle Angle