Which glidepath category requires A/P engagement at 80 Feet AGL?

Which glidepath category requires A/P engagement at 80 Feet AGL?

• A. Less than 3.5 degree glidepath angle
• B. Between 3.5 and 4.0 degree glidepath angle
• C. +4.0 degree glidepath angle
• D. All categories

Answer: (A)

When an instrument approach uses a very shallow glidepath (less than 3.5 degrees), there’s a greater chance that small altitude errors or wind effects can push you off the intended descent path as you near the runway. To keep you on track and maintain a stable approach, the procedure requires autopilot engagement by about 80 feet above the ground. This early or timely engagement helps the aircraft automatically correct and stay on the shallow path all the way to a safe landing. For glidepaths steeper than that, the margin for error is larger and the procedures don’t mandate autopilot engagement at 80 feet; pilots can rely on manual control or engage the autopilot at different points. So the need to engage autopilot at 80 feet AGL applies specifically to the shallower glidepath category.

When an instrument approach uses a very shallow glidepath (less than 3.5 degrees), there’s a greater chance that small altitude errors or wind effects can push you off the intended descent path as you near the runway. To keep you on track and maintain a stable approach, the procedure requires autopilot engagement by about 80 feet above the ground. This early or timely engagement helps the aircraft automatically correct and stay on the shallow path all the way to a safe landing.

For glidepaths steeper than that, the margin for error is larger and the procedures don’t mandate autopilot engagement at 80 feet; pilots can rely on manual control or engage the autopilot at different points. So the need to engage autopilot at 80 feet AGL applies specifically to the shallower glidepath category.