Ground Speed calculation requires flight in what regime?

Ground Speed calculation requires flight in what regime?

• A. Unaccelerated/cruising flight
• B. Climbing
• C. Descending
• D. Takeoff roll

Answer: (A)

Ground speed is how fast you’re moving over the ground, so you want a situation where wind and airspeed are steady. In unaccelerated cruising flight you’re flying straight and level with a constant true airspeed and a relatively constant wind along your route, which makes the ground speed a reliable, straightforward result of that TAS and the wind component along your track. Climbing or descending changes your airspeed and flight path angle, and wind can shift with altitude, so the ground distance covered per unit time isn’t constant. The takeoff roll is an accelerating phase with rapidly changing airspeed and wind effects, so ground speed isn’t stable there either. So the regime that allows accurate ground speed calculation is unaccelerated cruising flight.

Ground speed is how fast you’re moving over the ground, so you want a situation where wind and airspeed are steady. In unaccelerated cruising flight you’re flying straight and level with a constant true airspeed and a relatively constant wind along your route, which makes the ground speed a reliable, straightforward result of that TAS and the wind component along your track. Climbing or descending changes your airspeed and flight path angle, and wind can shift with altitude, so the ground distance covered per unit time isn’t constant. The takeoff roll is an accelerating phase with rapidly changing airspeed and wind effects, so ground speed isn’t stable there either. So the regime that allows accurate ground speed calculation is unaccelerated cruising flight.