Flight Control System Flashcards
Is there an aerodynamic feedback force to the T38 control system? If yes, explain it. If not, why?
No
Hydraulic power is used to control the T38 flight control system. The use of hydraulic power does not provide a direct mechanical connection to the flight control surfaces, thus there is no direct aerodynamic feedback
How does the artificial feel system work for the flight controls?
A system of springs for the aileron and rudder system provide a relative feel of feedback due to their position, and a system of springs and bobweights do the same for the stabilizer
Explain the rudder limiter system:
A mechanical linkage limits rudder pedal travel to set the travel limits for the rudder in certain configurations.
When the nose gear is extended 3/4 or less, rudder deflection is limited to 6 degrees. With greater than 3/4 deflection, rudder deflection is allowed the full 30-degrees
How does the trim system operate?
The trim system uses AC power to move the stick position relative to the artificial feel springs. The movement of the stick position adjusts the servo valves, releasing hydraulic pressure to the respective flight control surface, trimming the aircraft
How much can you trim the rudder with the rudder trim knob?
+/- 2 degrees in either direction
What is the stability augmenter system designed to do?
Reduce the T38s yaw tendencies
What two items must be on for the SAS to be activated?
Both the EGI switch and the Yaw damper switch
What is required for rudder trim to operate?
The SAS must be on
How does the SAS work?
Utility hydraulic pressure dampens yaw movements by moving the rudder
What is the power source for the speed brake?
The speed brake requires utility hydraulic pressure and DC electrical power
What is the difference between the front and rear speed brake switch?
The FCP has three detents in each position while the RCP is spring loaded to return to the center (OFF) position
Rear switch has priority
What does placing either speed brake switch into the centered (OFF) position do to the speed brake?
It removes hydraulic pressure from the speed brake
If you experience a DC power failure, what will happen to the speed brake?
It will freeze in its position
If there is a utility hydraulic failure, what will happen to the speedbrake?
It will creep from its last position
What happens to the speed brake below 250 psi utility hydraulic pressure?
The speed brake will not retract, even with the switch in the up position
What is the gear door switch in the FCP used to do?
It is used to control the position of the landing gear doors when the landing gear is extended
If you leave the gear door switch in the open position, will the gear doors retract when the landing gear is retracted?
Yes
When you pull the alternate release handle, what does it cut off from the landing gear?
It removes electrical and hydraulic power from the landing gear
How is the landing gear held into place when using the alternate release system?
By an overcenter lock
Under what 3 conditions is the gear up warning system activated?
The system is activated when the landing gear are not down and locked and:
- Airspeed is 210 KCAS or less
- Altitude is 10,000 ft or below
- Both throttles are below 96%
When flying with a single engine, what should you consider in regards to the gear up warning system?
It may not activated because the good engine may be above 96%
When does the red light in the handle appear when the gear warning system is not activated?
- When the gear handle is in the up position, the red light handle indicated the gear door position. If the red light in the handle is illuminated, all three landing gear doors are not up and locked
- When the gear handle is in the down position, the red light handle indicates the gear position. If the red light in the handle is illuminated, all three landing gear are not down and locked
When does the gear down warning system activate?
- The nose gear is down and locked
- Airspeed is greater than 240 KCAS on the MFD
or
- The nose gear is down and locked
- Airspeed is between 220-240 KCAS and accelerating at 2 knots per second with GS also increase
When is the nosewheel steering turned off?
- When the button is released
- When afterburner is selected
- Either start button is pressed
What is required for the NWS system to operate?
- There must be weight on the nose gear
- The lower button on either stick must be depressed
also
Utlility hydraulic pressure avail
DC electrical power avail
Start button not pressed
AB not selected
The hydraulic actuator for nosewheel steering gets its hydraulic fluid from where?
It shares hydraulic fluid with the fluid used to extend the nose gear. Thus, it gears hydraulic fluid from the utility system
Give a general description of the wheel brake system:
The wheel brake system is powered by a separate, self-contained hydraulic system with a single brake fluid reservoir. It is operated by pressure applied to the top of the rudder pedals
What is each brake pedal connected to?
A separate master cylinder
What brake pedal controls the brakes?
The brake pedal that has the greatest pressure applied to it
Do the flaps get their hydraulic power from the left or right engine?
Neither, the flaps are operated by right AC bus electrical power
What powers the flap switch and flap position indicator?
DC power
left essential DC bus
How do the FCP and RCP flap switches work in tandem?
They are connected mechanically by cables. The FCP switch is the only one connected to the electrical switch to activate the flap system
Describe the Flap-Slab Interconnect System
The flaps are mechanically connected to the Horizontal Tail (slab) via a flexible cable connected to the right flap. It assists the pilot with the pitch tendencies created when the flaps are extended
What are the three functions of the Flap-Slab Interconnect System?
- It automatically repositions the slab to reduce pitch trim changes as the flaps move
- It increases the amount of nose-down stick authority with the flaps extended
- It increases the amount of slab deflection per inch of stick travel
What does the Aux Flap Control Switch do in the Norm Position?
It allows for the flaps to be in either full up, 60%, or full down
What does the Aux Flap Control Switch do in the Emer Position?
You can set the flaps in any position from full up to down.
