WORKED DESCENT RATE CALCULATION: An aircraft executing an ILS final approach on a standard 3.0-degree glide slope maintains a groundspeed of 140 knots. What is the required rate of descent (ROD) in feet per minute to remain on the glide path?

1. 450 ft/min
2. 700 ft/min
3. 850 ft/min
4. 1,050 ft/min