What effect does a change in wind direction have on maintaining a 3° glide slope at constant true airspeed?

When considering the effect of a change in wind direction on maintaining a 3° glide slope at a constant true airspeed, it’s important to differentiate between the effects of headwinds and tailwinds.

When there is a tailwind, the aircraft's ground speed increases while it maintains the same true airspeed. As a result, to maintain the desired glide slope, the rate of descent must also increase. This is due to the need to cover the horizontal distance to the runway more quickly, given that the aircraft is moving faster across the ground.

Conversely, a headwind would decrease the ground speed but, since the true airspeed remains constant, the rate of descent required to maintain the glide slope would decrease because the aircraft is covering less ground distance over the same amount of time.

Thus, the correct option accurately reflects that as wind direction changes (to a tailwind), the ground speed increases and necessitates an increase in the rate of descent to maintain the 3° glide slope appropriately. This understanding is crucial for pilots to ensure they continue to adhere to the glide slope when faced with varying wind conditions during the approach phase.