EFTA00593629.pdf

PEDESTAL ESS SWITCHES FLAP EMER FLAP DC CONTROL a HANDLE OI FLAP FOLLOW UP Bus EMER VALVE T SWITCHES CONT • EXT -• C) C FLAP SHUTOFF VALVE A (DEENERGIZEDCLOSED) MANUAL FLAP RAP CONT FLAP INFORMATION CONTROL AUXILIARY RELAY PRESSURE COMBINED (OR UTILITY) O PRESSURE O O O O FLAP POSITION FOR TRAINING PURPOSES ONLY TRANSMITTEFt LEGEND - - - MECHANICAL STAB/FLAP INDICATOR STABILIZER INFORMATION FLAP/STAB a" POS 2 7 * BREAK CIRCUIT IF ACTUAL FLAP LINEAR TRAVEL EXCEEDS APPROX 1/4 INCH. ONE FROM THE OTHER C Figure 27-37. Flap Control System Block Diagram „5. EFTA00593629  FlightSafety GULFSTREAM GIV/G300/6400 MAINTENANCE TRAINING MANUAL Central Gearbox flaps being held in the desired position. If the selector valve solenoids fail, the emergency The central gearbox is mounted on the forward handle can be used to operate the valve. upper end of the torque box in the main wheel well. The gearbox has an input shaft and four output shafts. The input shaft is driven by the Flap Shutoff Valve hydraulic motor. The hydraulic motor is a The flap shutoff valve is located in the nose fixed displacement motor operating at 6,000 wheel well forward of the selector valve. It is rpm. This speed is reduced in the central gear- a single solenoid valve that must be energized box at a ratio of 8.22 to 1. Torque is transmitted open. When energized, it will allow hydraulic at a speed of 730 rpm to the spanwise torque fluid to the flap selector valve. It is energized shafts to drive the flaps and to drive the hor- whenever the flap control handle is moved. If izontal stabilizer. The fourth output is to the the flap control circuit breaker should blow due flap followup switch assembly and the posi- to an electrical failure in the normal flap con- tion transmitter. trol circuit, the valve can be energized through a separate circuit and the emergency flap con- Flap Control Handle trol handle can be used to move the flaps. Should a flap asymmetry occur during normal The flap control handle is located on the right or emergency operation, the shutoff valve will side of the center pedestal.It moves vertically be de-energized to prevent flap operation. into four detented positions: UP (0°), 10°, TAKEOFF/APPROACH (20°) and DOWN (39°). NOTES The emergency flap control handle is located on the copilot's side console.It is mechanically linked to the flap selector valve and is used as a manual override in the event of an electri- cal malfunction in the flap control valve. The handle moves vertically through three de- tented positions: UP, DOWN, and NEUTRAL. To operate the flaps with the emergency han- dle, move it in the desired direction and when the flaps reach the desired position return the handle to neutral. • Flap Selector Valve The flap selector valve is located in the nose wheel well, right side.It is a dual solenoid-op- erated valve. Solenoid "A" is energized for flaps up and solenoid "B" is energized for flaps down. The two positions provide re- versing hydraulic flow to the hydraulic motor for flap operation. The automatic stopping feature of the flaps is controlled by the flap fol- lowup switch assembly. When the flaps reach the desired position, one of the followup switches opens the electrical circuit to deen- ergize the respective solenoid valve. This results in the hydraulic motor stopping and the FOR TRAINING PURPOSES ONLY 27-65 EFTA00593630  FlightSafety GULFSTREAM GIU/G300/6400 MAINTENANCE TRAINING MANUAL ELECTRICAL OPERATION Flap/Stab Warning (S11)—Flaps full up, stab not at 1±1/4° Power for the flap control system is supplied by the FLAP CONT circuit breaker powered AFGCS (S l2)—Flaps any position except up, from the ESS DC bus. Additionally, the MAN- not used UAL FLAP CONT circuit breaker is powered through an integral switch in the FLAP CONT circuit breaker whenever it opens. NOTES The control system consists of four switches actuated by the flap control handle. Addi- tional control comes from the flap followup switch assembly. The assembly contains six flap position switches and five warning switches as well as control switches for other aircraft systems. These switches open and close as the flaps cycle through their range of 0 to 39°. As the flaps reach a selected position, the drive cam opens the particular switch, breaking•the circuit to the flap selector valve and halting flap movement. Of the six flap position switches, three control retraction and three control extension. UP (S1)—Retract 10° UP (S3)—Retract 10° Down (S4)—Extend 20° UP (S5)—Retract 20° DOWN (S6)—Extend DOWN (S2)—Extend The remaining switches in the assembly also open and close through the drive cam action in correspondence to flap position w allow cer- tain circuits to be completed. Landing Gear Warning Horn (S7)—Flaps equal to or greater than 22° Takeoff Alarm (S8)—Flaps full up or down Hydraulic Control (S9), not used Speedbrake/Flap Alarm (S 10)—Flaps any po- sition except up FOR TRAINING PURPOSES ONLY 27-67 EFTA00593631