AFOQT: Instrument Comprehension Review

These questions are designed to test your familiarity with and understanding of common instruments.
The question format will vary depending on the types of instruments that the test covers. The compass and the artificial horizon are two instruments commonly used in airplanes.
Test questions related to these instruments will illustrate a compass and an artificial horizon inside an airplane cockpit. Based on the readings of both of these instruments, you will have to determine the position and orientation of the airplane.

How Do I Read the Compass and Artificial Horizon Instruments?
The compass, a relatively intuitive instrument with which many people are familiar, shows which direction a person or vehicle is facing. When a person is facing north, for example, the needle on the compass points toward the 'N.' If the person is facing a direction between south and southeast, the needle will point between 'S' and 'SE.'

The artificial horizon is an instrument that shows how the nose and wings of a plane are tilted. For most people, the artificial horizon is less intuitive and less familiar than the compass. However, if you imagine yourself actually flying in a plane, the artificial horizon becomes easier to read and understand.
The artificial horizon has two components that illustrate how the nose of an airplane is tilted with respect to the ground: the miniature wings and the horizon bar. The miniature wings represent the actual wings of the aircraft, and the horizon bar represents the horizon, the imaginary line that divides the ground and the sky from the pilot's point of view. When the miniature wings are level with the horizon bar, the plane is level. When the miniature wings are above the horizon bar, the plane is tilted upward, and when the miniature wings are below the horizon bar, the plane is tilted downward. These categories of nose tilt are shown in the drawing below.

To illustrate how the wings are tilted from side to side, the artificial horizon instrument also has a dial with degree marks representing the bank angle. A needle on the dial indicates the exact bank angle, and the horizon bar is tilted accordingly, as shown in the picture below. If the left wing of the plane is tilted downward, the needle will be to the right of the center of the dial; if the right wing is tilted downward; the needle will be to the left of the center. Note that the tilted horizon bar reflects the pilot's point of view: if the left wing of the plane is tilted downward, the horizon will appear to be tilted in the opposite direction.

To answer the questions, you will have to use information from both the compass and artificial horizon to determine how the plane is oriented. If the plane is flying north, it will appear to fly into the page in the illustrations.

For example, based on the compass and artificial horizon shown below, which of the answer choices represents the orientation of the plane?

ANSWER: The answer is A.

First, notice that the compass is pointing in a west-southwest direction. If a north-flying plane is facing into the page, then a westbound plane will be facing left. The compass indicates that the plane is flying somewhere between west and southwest, so the illustration will show a plane that appears to be facing left and just slightly out of the page.
Second, notice that the miniature wings in the artificial horizon are above the horizon line, and the needle on the dial is to the left of the center. From this information, you know that 1) the nose of the plane is tilted upward, and 2) the left wing of the plane is tilted upward, and the right wing is tilted downward. Because only the plane illustrated in choice A fits this description, it is the correct answer.

How Can I Improve My Ability to Read the Compass and Artificial Horizon?
Most people don't encounter these instruments on an everyday basis, so the best way to improve your ability to read them is simply to do the practice question in this section. However, although the artificial horizon is not commonly found outside of aircraft, you might want to practice using a real compass if you are still having trouble with these questions. You can find a reasonably-priced compass at most outdoor or sporting goods stores.