词汇与结构
When higher forces are required to generate sufficient elevator control to flare for landing, stabilizer trim is available to _________ the sustained control column force.
When higher forces are required to generate sufficient elevator control to flare for landing, stabilizer trim is available to _________ the sustained control column force.
举一反三
- 词汇与结构 If the jam exists during the landing phase, higher forces are required to generate sufficient elevator control to _________ for landing.
- 词汇与结构 Although total available elevator travel is significantly reduced, there is _________ elevator travel available for landing flare.
- 词汇与结构 In the event of a control column jam, an override _________ allows the control columns to be physically separated.
- 词汇与结构 Pull the control stick all the way back to the stop. This places our elevator in a full up position allowing for the relative wind to put a ______ force on the tail.
- In many airplanes, the elevator is controlled by two cables: a “down” cable and an “up” cable. Normally, a break or disconnect in only one of these cables will not result in a total loss of elevator control. In most airplanes, a failed cable results in a partial loss of pitch control. In the failure of the “up” elevator cable the control yoke will move aft easily but produce no response. Forward yoke movement, however, beyond the neutral position produces a nose down attitude. Conversely, a failure of the “down” elevator cable, forward movement of the control yoke produces no effect. The pilot will, however, have partial control of pitch attitude with aft movement. When experiencing a loss of up-elevator control, the pilot can retain pitch control by: • Applying considerable nose-up trim. • Pushing the control yoke forward to attain and maintain desired attitude. • Increasing forward pressure to lower the nose and relaxing forward pressure to raise the nose. • Releasing forward pressure to flare for landing. When experiencing a loss of down-elevator control, the pilot can retain pitch control by: • Applying considerable nosedown trim. • Pulling the control yoke aft to attain and maintain attitude. • Releasing back pressure to lower the nose and increasing back pressure to raise the nose. • Increasing back pressure to flare for landing. Trim mechanisms can be useful in the event of an in-flight primary control failure. For example, if the linkage between the cockpit and the elevator fails in flight, leaving the elevator free to weathervane in the wind, the trim tab can be used to raise or lower the elevator, within limits. The trim tabs are not as effective as normal linkage control in conditions such as low airspeed, but they do have some positive effect — usually enough to bring about a safe landing. If an elevator becomes jammed, resulting in a total loss of elevator control movement, various combinations of power and flap extension offer a limited amount of pitch control. A successful landing under these conditions, however, is problematical.