FAA Private Pilot Airplane (PAR)Navigation and Flight PlanningMedium
A pilot is planning a VFR cross-country flight at 7,500 feet MSL. The planned true airspeed is 100 knots. The forecast winds aloft at 7,000 feet MSL are 270 at 20 knots. The true course for the first leg is 090 degrees. Approximately what is the required wind correction angle and resulting ground speed?
- A8 degrees right, 120 knots
- B11 degrees right, 100 knots
- C8 degrees left, 82 knots
- D11 degrees left, 81 knots
Show answer & explanationAnswer & explanation
Correct answer: D. 11 degrees left, 81 knots
To solve this, a flight computer (E6B) or equivalent calculation is used. With a true airspeed of 100 knots, a true course of 090 degrees, and a wind of 270 at 20 knots, the wind correction angle is 11 degrees left, and the ground speed is 81 knots. This scenario involves a direct headwind component.
Why the other options are wrong
- A. Incorrect wind correction direction and ground speed. A headwind does not increase ground speed.
- B. Incorrect wind correction direction (right instead of left) and ground speed. A direct headwind would decrease ground speed.
- C. Incorrect calculation of wind correction angle and ground speed. A common error is misinterpreting the wind direction.
Wind Correction Angle (WCA) & Ground Speed (GS)
WCA is the angle an aircraft must be turned into the wind to maintain a desired true course. Ground speed is the speed of the aircraft relative to the ground, affected by true airspeed and wind.
- WCA compensates for wind drift to maintain desired course.
- Ground speed is TAS adjusted for headwind/tailwind components.
- Calculated using a flight computer (E6B) or advanced navigation systems.
Memory trick: Wind Changes Airspeed, Course, and Ground Speed.