SWA B737 - Flight Controls

Question 1

(Flight Controls) What are the Primary Flight Controls?

Answer 1

• Ailerons
• Rudder
• Elevator

Question 2

(Flight Controls) How does Manual Reversion work?

Answer 2

If we lose Hydraulic System A and B:
• The ailerons can still be mechanically positioned by the Pilot’s Control Wheel (Control Forces are higher due to Friction and Aerodynamic Loads)
• The elevator’s can still be mechanically positioned by forward or aft movement of the Pilot’s Control Columns

Question 3

(Flight Controls) What System controls the Flight Spoilers?

Answer 3

There are a total of 8 Flight Spoilers
• Hydraulic System A controls 4 Flight Spoilers
• Hydraulic System B controls 4 Flight Spoilers

Question 4

(Flight Controls) What is the Aileron Transfer Mechanism?

Answer 4

A way to isolate the Aileron system from the Flight Spoilers if a jam occurs
• If the Aileron Control System is jammed - force applied to the First Officer’s Control Wheel provides roll control from the Spoilers (the Aileron’s and Captain’s control wheel are inoperative)
• If the Spoiler’s are jammed - force applied to the Captain’s Wheel provides Roll Control from the Aileron’s (the Spoilers and FO’s Control Wheel are inoperative)

Question 5

(Flight Controls) What Hydraulic System does the Elevator Feel Computer use?

Answer 5

Either A or B (whichever happens to be higher at the time)

Question 6

(Flight Controls) What does an illuminated FEEL DIFF PRESS light on the Flight Control Panel on the Overhead Panel indicate?

Answer 6

Either Hydraulic System or Elevator Feel Pitot System has failed - excessive differential pressure is sensed in the Elevator Feel Computer

Question 7

(Flight Controls) What happens in the case of a Control Wheel jam in regards to the elevator?

Answer 7

Applying force against the jam will breakout either the Captain’s or First Officer’s Control Column - the Control Column that moves freely after the breakout provides adequate Elevator control for the remainder of the flight (Column forces are higher and exceed those experienced during manual reversion)

Question 8

(Flight Controls) What are the PCU’s that control the rudder?

Answer 8

• Main Rudder PCU (powered by Hydraulic System A and B)

* Standby Rudder PCU (powered by the Standby Hydraulic System)

Question 9

(Flight Controls) When is Hydraulic Pressure reduced in the Main Rudder PCU?

Answer 9

At speeds above 135 knots (This limits full rudder authority in flight after takeoff and before landing, while preserving full authority for takeoff and landing)

Question 10

(Flight Controls) What is the Force Fight Monitor?

Answer 10

Detects opposing pressure between Hydraulic System A and B actuators in the Main Rudder PCU (this may occur if either input is jammed or disconnected). The Force Fight Monitor will automatically turn on the Standby Hydraulic Pump and open the Rudder SOV to pressurize the Standby Rudder PCU

Question 11

(Flight Controls) If the Rudder Trim Indicator fails, does that mean the Rudder Trim has also failed?

Answer 11

No - you can still use the Rudder Trim

Question 12

(Flight Controls) What does an illuminated YAW DAMPER light on the Flight Control Panel on the Overhead Panel indicate?

Answer 12

The Yaw Damper is NOT engaged

Question 13

(Flight Controls) When does the Mach Trim System automatically engage?

Answer 13

Mach .615 and Greater (Helps to prevent Mach Tuck - as airspeed increases Center of Lift moves aft and the airplane starts to exhibit a Nose Down tendency)

Question 14

(Flight Controls) What does an illuminated MACH TRIM light on the Flight Control Panel on the Overhead Panel indicate?

Answer 14

Failure of the Mach Trim System (this is a Dual Channel System)

Question 15

(Flight Controls) What does an illuminated SPEED TRIM FAIL light on the Flight Control Panel on the Overhead Panel indicate?

Answer 15

The Speed Trim System has failed (This is a Dual Channel System)

Question 16

(Flight Controls) What does an illuminated SPEEDBRAKES EXTENDED light above the First Officer’s MD indicate?

Answer 16

IN FLIGHT -
Warns the flight crew the Speed Brakes are extended while in the landing configuration:
• Trailing Edge Flaps extended more than 10 degrees OR
• Radio Altitude below 800 feet

ON THE GROUND -
• The SPEED BRAKE Lever is DOWN, and the Ground Spoilers are NOT stowed

Question 17

(Flight Controls) What does an illuminated SPEED BRAKE DO NOT ARM light above the Captain’s MD indicate?

Answer 17

An abnormal condition or test inputs to the automatic Speed Brake System (light is deactivated with the SPEED BRAKE lever in the DOWN detent position)

Question 18

(Flight Controls) What happens with the Speed Brake Lever upon touchdown?

Answer 18

It automatically moves to the UP position and all flight and ground spoilers extend

Question 19

(Flight Controls) What conditions cause the automatic deployment of the Speed Brakes?

Answer 19

All of the following conditions have to be met:
• SPEED BRAKE lever ARMED
• SPEED BRAKE ARMED light illuminated
• Thrust Levers IDLE
• Main Landing Gear Wheel Spin Up (More than 60 knots)
• Landing Gear Strut Compression on Touchdown
• Radio Altitude less than 10 feet

Question 20

(Flight Controls) If the Speed Brake Lever is in the DOWN position, what conditions will automatically cause it to the UP position and use all Ground and Flight Spoilers?

Answer 20

All of the following conditions have to be met:
• Landing Gear Wheel Spin up (mire than 60 knots)
• Thrust Levers IDLE
• Reverse Thrust Levers positioned for Reverse Thrust

Question 21

(Flight Controls) If you just landed or performed an RTO, can you automatically retract all the spoilers?

Answer 21

Yes - by advancing either Thrust Lever, the Speed Brake Lever automatically moves to the DOWN position and all spoiler panels retract

Question 22

(Flight Controls) What does an illuminated LE FLAPS TRANSIT light under the Flap Indicator indicate?

Answer 22

Any of the following:
• LE Device in Transit
• LE Device Not in Programmed Position
• LE Slat Skew Condition Exists (This light is inhibited during Autoslat Operation)

Question 23

(Flight Controls) What is the Autoslat System?

Answer 23

On takeoff or approach to landing, if the airplane is approaching a Stall Condition the Slats automatically extend to FULL EXT position prior to stick shaker activation, in an attempt to prevent a stall. When the pitch angle is reduced below the stall critical attitude the Slats return to the EXT position (For autoslat to work, the Slats need to be in the EXT position- they won’t work if they aren’t extended, i.e. Flaps Up)

Question 24

(Flight Controls) What does an illuminated AUTO SLAT FAIL light on the Flight Control Panel on the Overhead Panel indicate?

Answer 24

The Autoslat function is not available (This is a dual channel light)

Question 25

(Flight Controls) What is Flap Load Relief?

Answer 25

On the 700 only works at Flaps 30 and 40.
• Flaps 40 - Flaps will automatically retract to 30 if airspeed is greater than 163 knots (re-extend to 40 when airspeed falls below 158 knots)
• Flaps 30 - Flaps will retract to 25 if airspeed is greater than 176 knots (re-extend to 30 when airspeed is less than 171 knots)