A pilot spots the start of a runway as he begins his descent. Which angle indicates an angle of depression?

An **angle of depression** is the angle formed between the horizontal line of sight and the line of sight downward to an object. In the context of aviation: - **Pilot's Perspective:** - **Horizontal Line:** Imagine a straight, horizontal line extending directly in front of the pilot's eyes. - **Line of Sight:** This is the line from the pilot's eyes to the point he's observing—in this case, the start of the runway. - **Angle of Depression:** - The angle between the **horizontal line** and the **line of sight downward** to the runway is the **angle of depression**.  *Illustration: The horizontal line represents the pilot's eye level. The dashed line shows the line of sight to the runway, and the angle between them is the angle of depression.* **Key Points:** - **Measurement:** The angle of depression is measured from the horizontal downward to the line of sight. - **Equal to Angle of Elevation:** If you were to look up from the runway to the pilot, the angle formed would be the **angle of elevation**, which is equal in measure to the angle of depression due to alternate interior angles formed by parallel lines. **Example Scenario:** - If the pilot's horizontal line is perfectly level and his line of sight tilts downward at 3°, then the angle of depression is **3 degrees**. **Identifying the Angle:** - Look for the angle that starts at the pilot's eye level (horizontal) and moves downward toward the runway. - This downward-tilted angle relative to the horizontal is the **angle of depression**. If you have specific options or a diagram you'd like help with, feel free to share more details!