There are several objectives in demonstrating these various maneuvers. 

1. They teach pilots to understand the susceptibility of the human system to spatial disorientation. 

2. They demonstrate that judgments of aircraft attitude based on bodily sensations are frequently false. 

3. They help decrease the occurrence and degree of disorientation through a better understanding of the relationship between aircraft motion, head movements, and resulting disorientation. 

4. They help instill a greater confidence in relying on flight instruments for assessing true aircraft attitude. 

A pilot should not attempt any of these maneuvers at low altitudes or in the absence of an instructor pilot or an appropriate safety pilot. 

## Climbing While Accelerating 

With the pilot’s eyes closed, the instructor pilot maintains approach airspeed in a straight-and-level attitude for several seconds, then accelerates while maintaining straight-and­ level attitude. The usual illusion during this maneuver, without visual references, is that the aircraft is climbing. 

## Climbing While Turning 

With the pilot’s eyes still closed and the aircraft in a straight­ and-level attitude, the instructor pilot now executes, with a relatively slow entry, a well coordinated turn of about 1.5 positive G (approximately 50° bank) for 90°. While in the turn, without outside visual references and under the effect of the slight positive G, the usual illusion produced is that of a climb. Upon sensing the climb, the pilot should immediately open the eyes to see that a slowly established, coordinated turn produces the same sensation as a climb. 

## Diving While Turning 

Repeating the previous procedure, but with the pilot’s eyes should be kept closed until recovery from the turn is approximately one-half completed, can create the illusion of diving while turning. 

## Tilting to Right or Left 

While in a straight-and-level attitude, with the pilot’s eyes closed, the instructor pilot executes a moderate or slight skid to the left with wings level. This creates the illusion of the body being tilted to the right. 

## Reversal of Motion 

This illusion can be demonstrated in any of the three planes of motion. While straight and level, with the pilot’s eyes closed, the instructor pilot smoothly and positively rolls the 

aircraft to approximately 45° bank attitude while maintaining heading and pitch attitude. This creates the illusion of a strong sense of rotation in the opposite direction. After this illusion is noted, the pilot should open his or her eyes and observe that the aircraft is in a banked attitude. 

## Diving or Rolling Beyond the Vertical Plane 

This maneuver may produce extreme disorientation. While in straight-and-level flight, the pilot should sit normally, either with eyes closed or gaze lowered to the floor. The instructor pilot starts a positive, coordinated roll toward a 30° or 40° angle of bank. As this is in progress, the pilot tilts his or her head forward, looks to the right or left, then immediately returns his or her head to an upright position. The instructor pilot should time the maneuver so the roll is stopped as the pilot returns his or her head upright. An intense disorientation is usually produced by this maneuver, and the pilot experiences the sensation of falling downward into the direction of the roll. 

In the descriptions of these maneuvers, the instructor pilot is doing the flying, but having the pilot do the flying can also be a very effective demonstration. The pilot should close his or her eyes and tilt the head to one side. The instructor pilot tells the pilot what control inputs to perform. The pilot then attempts to establish the correct attitude or control input with eyes closed and head tilted. While it is clear the pilot has no idea of the actual attitude, he or she will react to what the senses are saying. After a short time, the pilot will become disoriented and the instructor pilot will tell the pilot to look up and recover. This exercise allows the pilot to experience the disorientation while flying the aircraft. 

## Coping with Spatial Disorientation 

To prevent illusions and their potentially disastrous consequences, pilots can: 

1. Understand the causes of these illusions and remain constantly alert for them. Take the opportunity to experience spatial disorientation illusions in a device, such as a Barany chair, a Vertigon, or a Virtual Reality Spatial Disorientation Demonstrator. 

2. Always obtain and understand preflight weather briefings. 

3. Before flying in marginal visibility (less than 3 miles) or where a visible horizon is not evident, such as flight over open water during the night, obtain training and maintain proficiency in aircraft control by reference to instruments. 

4. Do not fly into adverse weather conditions or into dusk or darkness unless proficient in the use of flight instruments. If intending to fly at night, maintain 

