If an elevator fails on an airplane, the consequences can be severe, primarily affecting the pilot's ability to control the aircraft's pitch (nose-up or nose-down movement).
Understanding Elevator Function
Before diving into failure scenarios, it's essential to understand the elevator's role. The elevator is a control surface located on the tail of an aircraft, which, when manipulated by the pilot, changes the angle of the aircraft’s nose relative to the horizon. This control is crucial for:
- Ascending and descending
- Maintaining level flight
- Adjusting speed during takeoff and landing
Failure Scenarios and Consequences
Complete Linkage Failure
If the entire linkage between the pilot’s controls and the elevator fails, the elevator is no longer under the pilot's control. According to the provided reference, the elevator could be left to weathervane freely in the wind. This means the elevator will move with the wind, essentially becoming uncontrolled, and you are left with no nose-up or nose-down pitch control through the yoke or stick.
Implications of No Pitch Control
The inability to control pitch has significant implications:
- Loss of Controlled Flight: Without pitch control, maintaining level flight becomes challenging, and the aircraft's altitude may vary uncontrollably.
- Difficulty During Critical Phases: Takeoffs and landings, which require precise pitch adjustments, become extremely dangerous, if not impossible.
- Recovery Challenges: Recovering from unusual attitudes, like a steep climb or descent, will be hampered.
Alternative Control Options
In case of complete elevator failure, it’s important to note that, although not as effective as an operational elevator, pilots may attempt to maintain limited pitch control using the following:
- Trim System: The trim system can provide some level of pitch control by adjusting the elevator's position. However, it’s a slow system and designed for fine tuning, not major corrections.
- Thrust: By carefully adjusting the thrust of the engines, pilots may be able to influence the pitch to some extent, though this requires a deft touch.
- Air brakes: Air brakes can be used to affect the speed of the aircraft which influences the pitch.
Summary
A failed elevator, especially a complete linkage failure, is a serious issue, leading to a lack of pitch control. Pilots may have limited control options in such cases, but it poses significant challenges to maintaining safe and controlled flight.
