Which of the following is NOT a criterion for calculating Ground Speed?

Which of the following is NOT a criterion for calculating Ground Speed?

• A. Inside slant range
• B. On radial of a NAVAID
• C. In unaccelerated/cruising flight
• D. Have already set IAS for TAS

Answer: (C)

Ground speed is how fast you’re actually moving over the ground, which comes from your true airspeed and the wind along your flight path. To calculate it, you need TAS (which you get from IAS at a given altitude/temperature) and the wind component along your course. You don’t have to be in a specific flight phase for the calculation; ground speed can be determined even if you’re accelerating, turning, or changing airspeed. The other statements describe situational details or steps used in navigation work (distance to a station within slant range, being on a VOR radial, or converting IAS to TAS), but they aren’t required prerequisites for performing the ground speed calculation itself. So the idea that you must be in unaccelerated/cruising flight isn’t a necessary criterion.

Ground speed is how fast you’re actually moving over the ground, which comes from your true airspeed and the wind along your flight path. To calculate it, you need TAS (which you get from IAS at a given altitude/temperature) and the wind component along your course. You don’t have to be in a specific flight phase for the calculation; ground speed can be determined even if you’re accelerating, turning, or changing airspeed. The other statements describe situational details or steps used in navigation work (distance to a station within slant range, being on a VOR radial, or converting IAS to TAS), but they aren’t required prerequisites for performing the ground speed calculation itself. So the idea that you must be in unaccelerated/cruising flight isn’t a necessary criterion.