AI.II.I.K5aFAA-S-ACS-25 · Nov 2023Knowledge
a. Time, climb and descent rates, course, distance, heading, true airspeed, and grounds...
Calculating: a. Time, climb and descent rates, course, distance, heading, true airspeed, and groundspeed
Bottom line
Groundspeed is determined by combining the movement of the aircraft with that of the air mass. Groundspeed can be computed by the time required to fly between two points a known distance apart. To arrive at compass heading, after the true course is measured and wind correction applied resulting in a true heading, the sequence TH ± variation = magnetic heading ± deviation = compass heading is followed.
Key numbers
| Number | What it means |
|---|---|
| 250 KIAS below 10,000 feet MSL | Speed limit |
| 1 mile per 10 knots of head or tail wind at cruise altitude | Wind adjust |
| about 10 KIAS lost per mile in level flight | Deceleration |
| approximately 3 degrees | Descent path |
FAA references
- PHAK ch. 16 (p. 16-9) — FAA-H-8083-25C (2023)
- AFH ch. 16 (pp. 16-17–16-18) — FAA-H-8083-3C
- AFH ch. 3 (p. 3-23) — FAA-H-8083-3C
- RMH ch. 3 (p. 3-14) — FAA-H-8083-2A
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