MANUAL REVERSION or LOSS OF SYSTEM A AND SYSTEM B

in #b737 • 6 years ago

FCTM 8.x [Hydraulic System(s) Inoperative - Landing]

X with one or both hydraulic system fluid quantities not zero, verify the EDP.
The EMDP are located in the E&E, so these pumps cannot be reset in FLT.

FLT CONTROL switches (both) ............ Confirm ............................ STBY RUD

When moving the first switch to STBY RUD, closely observe that :

  • The System Flight Control LOW PRESSURE amber light extinguishes
  • The STBY RUD ON amber light illumonates
  • The Standby Hydraulic LOW QUANTITY amber light does not illuminate
  • The Standby Hudraulic LOW PRESSURE amber light illuminates momentarily, then extinguishes (this confirms pump engagement) However, with a loss of system A or B on GND and wheel speed above 60 kts or airborne and flaps extended, the Standby Hydraulic pump engages automatically, and consequently the LOW PRESSURE amber light will not momentarily illuminate anymore.

If the Standby Hydraulic LOW PRESSURE amber light remains illuminated the Standby Hydraulic System is inoperative.
Refer to SUBSEQUENT FAILURE(S).

Automatic Flight
Autopilots inoperative - disconnect A/T due to excessive pitch variations - PM may assist as 'autothrottle'

Engines, APU
Both engines have standby system pressure for reverser operation.
Expect a delayed and slower deployment and possible illumination of the Standby Hydraulic LOW QUANTITY amber light during roll-out due to fluid moving from the Standby System to System A-B through the reverser return-line

Flight Controls
Alternate flaps extension. Extension to F15 takes about 2 minutes.
Respect flaps limit placard speeds. No asymmetry protection !
Electric trim available - Trim airplane slightly nose up to remain outside elevator cable control dead band
(As installed) The WTRIS commands a small amount of movement to the standby rudder PCU when the captain's control wheel is rolled, to help airplane turns. The rudder pedals do not reflect rudder deflections commanded by the WTRIS.
If the WTRIS is not installed or the F/O is PF, minor rudder inputs may assist in entering turns and in maintaining directional control on final. However this technique is not recommended.
Ground Spoilers and Flight Spoilers are inoperative - Limit bank angle to 20 degrees to avoid over-banking. Roll rate in turns and speedbrake effectiveness in descent is reduced.
Yaw damper has standby hydraulic pressure, position Yaw Damper Switch back to ON.

Landing Gear
Expect manual gear extension. Once extended, the landing gear cannot be retracted.
Normal and alternate nose wheel steering are inoperative
Brakes have accumulator pressure only - Autobrakes INOP
Antiskid is available on accumulator brakes

Approach
Burn-off fuel to a practical minimum to reduce landing weight.
Avoid overweight landing
Start with flaps and gear extension when fuel is 1,000 kg / 2,000 lbs above minimum reserve and ATC guarantees a landing clearance.
Body attitude approximately 2 degrees

Landing
SOP Landing minima CAT I - Verify Lower Landing Minimums Requirement Table
Choose RWY :

  • weather forecast at ETA (= after fuel burn-off)
  • refer to PI [Advisory Info - Non-Normal Configuration Landing Distance]
  • avoid wet runway and crosswind
  • verify obstacles for straight ahead go-around
    Flaps 15 - no flare, positive landing - aircraft has tendency to float or bounce due to inoperative spoilers - apply forward column pressure after nose wheel touchdown
    Apply steady moderate brake pressure for optimal use of the accumulator pressure. During landing roll, the PM can call-out the remaining brake accumulator pressure.
    Do not attempt to taxi after landing, accumulator pressure may be depleted! The pre-charge pressure of 1,000 PSI cannot be used for braking!

Go-around
Go-around with Flaps 15 and Gear down
Slowly advance thrust levers to avoid unstable pitch-up

Diversion
Retract the TE flaps to UP using the alternate flap system. The LE devices remain in Mid (after T/O) or Full (T/O or G/A) Extend.
With the LE devices in full extend, limit airspeed to 230 kts (=ALT FLAP EXTEND placard speed) and do not climb above 20,000 ft.
The FMC does not provide fuel progress data for flight with landing gear down ! Calculate alternate fuel with a penalty 50 % (Gear Down) and another 10 % (LED extended).
Refer to PI [Gear Down - LRC Enroute Fuel and Time]

ATC
Advise ATC that you have lost all hydraulic systems and that you have difficulties in maintaining level flight and directional control
Request :

  • weather forecast at ETA (=after fuel burn-off)
  • 2,000 feet vertical separation with other traffic
  • radar vectors for 15 miles final
  • landing clearance prior to leave the holding
  • straight ahead go-around procedure

Report :

  • time required in holding to burn-off fuel and to prepare for approach
  • souls on board
  • fuel upon landing
  • any or no dangerous goods on board

Advise ATC that you are unable or have difficulty in vacating the runway after landing due to an inoperative nose wheel steering

Ground Handling
Request towing assistance near the landing runway

Cabin Crew
SOP - Brief the CCM using company guidelines and call-outs

Passengers
SOP - Reassure passengers in line with company guidelines
Example : "Major technical problem, airplane under control. Remain in holding for x time to reduce fuel. Follow Cabin Crew instructions."

SUBSEQUENT FAILURE (S)

LOSS OF STANDBY HYDRAULIC SYSTEM

Perform the NNC [STANDBY HYDRAULIC LOW PRESSURE]

  • Rudder control is lost
  • Both engine reversers are inoperative. Refer to PI [Advisory Info - Normal Configuration Landing Distance] and obtain the landing distance adjustment from the NO REV column.
#hydraulic
6 years ago in #b737 by
$0.00
    Reply 0