Which illusion causes pilots to treat a sloping cloud deck as the horizon, leading to incorrect attitude?

Which illusion causes pilots to treat a sloping cloud deck as the horizon, leading to incorrect attitude?

• A. Autokinesis
• B. False Horizon
• C. Orientation Illusion
• D. Induced Motion

Answer: (B)

When you can’t see a real horizon, your brain looks for something that resembles one. A sloping cloud deck can form a tilted line that looks like the horizon, so you perceive the aircraft as level even though you’re actually banked or pitched differently. This misread of attitude happens because the visual cue you’re using to judge orientation is misleading, so the airplane attitude you think you’re in is not the actual attitude. To counter this, rely on the flight instruments, especially the attitude indicator, and cross-check with other instruments (altimeter, vertical speed, airspeed) to confirm your true attitude. The other options describe different perceptual effects (autokinesis is a stationary light moving in darkness; induced motion involves motion of surrounding objects; orientation illusion is a broader category of body-orientation misperceptions), but they don’t specifically explain the false horizon caused by a sloping cloud deck.

When you can’t see a real horizon, your brain looks for something that resembles one. A sloping cloud deck can form a tilted line that looks like the horizon, so you perceive the aircraft as level even though you’re actually banked or pitched differently. This misread of attitude happens because the visual cue you’re using to judge orientation is misleading, so the airplane attitude you think you’re in is not the actual attitude.

To counter this, rely on the flight instruments, especially the attitude indicator, and cross-check with other instruments (altimeter, vertical speed, airspeed) to confirm your true attitude. The other options describe different perceptual effects (autokinesis is a stationary light moving in darkness; induced motion involves motion of surrounding objects; orientation illusion is a broader category of body-orientation misperceptions), but they don’t specifically explain the false horizon caused by a sloping cloud deck.