Final answer:
The rate of descent for a 3-degree glide slope at a speed of 120 knots is approximately 600 feet per minute, which is the closest answer to the calculated 636.53 feet per minute.
Step-by-step explanation:
This means that for every 100 feet forward, the descent is 5.24 feet. If an aircraft is flying at a common approach speed, let's assume 120 knots (which is 120 nautical miles per hour), this translates to 120 x 6076 feet/hour because there are 6076 feet in a nautical mile.
That gives us a forward movement of approximately 728,160 feet per hour. To find the rate of descent, we multiply the forward movement per hour by the tangent of the glide angle: 728,160 x 0.0524 = 38,191.744 feet per hour. Converted to minutes, we have 38,191.744 / 60 = 636.53 feet per minute. Since the answer choices are in increments of 300 feet per minute, the closest approximate rate of descent is 600 feet per minute (Option B).