Landing Gear Flashcards
LGEAR_001
Recall the minimum hyd pressure necessary to set the parking brake:
A minimum of 1400 psi (88) / 1700 psi (90) on BRAKE PRESS gauges is required prior to setting the parking brake to ensure adequate brake holding power.
LGEAR_003
Recall what an amber ABS light indicates:
Illuminates when the landing gear handle is down, AUTO BRAKE selector is moved out of the OFF position - AUTO BRAKE ARM/DISARM switch is in DISARM.
LGEAR_004
Recall the conditions for availability of antiskid braking:
- The antiskid system is electronically controlled and is operational when:
- Switch in ARM position
- Gear handle down or alt gear handle pulled
- Parking brakes released
- Wheel speed greater than 10 knots
Note: Anti-skid braking is not available if the left / right DC busses are unpowered.
LGEAR_005
Recall auto brakes are available in normal brake system only:
When should autobrakes not be used?
When is ABS unavailable?
- The anti-skid system must be armed and operational for ABS operation.
- With left and/or right hydraulic system failure, do not use Autobrakes.
- ABS is unavailable if the flaps are less than 26 degrees for landing or if the accumulators are the only source of hydraulics.
LGEAR_006
Recall the conditions required for autobrake RTO system operation:
- The ABS takeoff mode is activated during a rejected takeoff upon spoiler handle extension. Note: If spoiler handle fails to deploy automatically, manual spoiler handle deployment will activate ABS.
- If a rejected takeoff is initiated below 70 knots (88) / 90 knots (90), the ABS reverts to landing mode operation and MIN braking is provided.
- At speeds greater than 70 knots (88) / 90 knots (90), maximum dual-system automatic braking is applied immediately without any time delay.
Note: Full right and left brake system pressure is applied to the brakes and maximum deceleration is limited only by antiskid operation.
LGEAR_007
Recall the conditions required for ABS operation during landing:
- ABS landing mode is activated when the spoiler handle is deployed either automatically or manually with throttles retarded and brake pedals released.
- Automatic braking is delayed after spoiler deployment for approximately 1 second in MAX position and approximately 3 seconds (88) / 1second (90) in MIN or MED positions. ABS landing mode is inhibited if the throttles are not retarded towards idle.
Note: With MED selected, brake system pressure is modulated to the brakes by the land manifold to maintain a fixed level of deceleration. However, with MAX selected, full right brake system pressure is applied to the brakes and maximum deceleration is limited only by anti-skid operation.
LGEAR_002
Recall the brake pedal deflection that will disengage automatic braking (autobrakes):
MD-88
- Autobrakes are disarmed at any speed by depressing brake pedals beyond 25% travel.
MD-90
- Below 90 knots, 25% pedal deflection is required to disengage autobrakes.
- Above 90 knots, 90% pedal deflection is required to disengage autobrakes.
LGEAR_008
Recall the maximum brake temperatures for takeoff and setting the parking brake: (MD-88)
MD-88:
- Max brake temperature for setting parking brakes is 300°C.
- Prior to takeoff, verify brake temperature does not exceed 205°C and OVHT light extinguished.
MD-90:
- Max brake temperature for setting parking brakes is 500°C.
- Prior to takeoff, verify OVHT light extinguished and BRAKE TEMP gauge does not exceed 250°C for airport elevations up to 2,200’ MSL.
- Corrections to takeoff brake temperature limits: - When OAT exceeds 32°C, subtract 5°C for each 1°C above 32°C. - For each 1 knot of tailwind, subtract 15°C.
- For takeoff from higher airport elevations or higher brake temperatures refer to guidance in VOL.1 NP and ODM.
LGEAR_010
During what aircraft condition will GEAR HORN OFF button not silence gear warning?
Pushing the GEAR HORN OFF button will silence landing gear warning horn and vocal warning under all conditions of descent and approach except when gear is not down and flaps are extended beyond approximately 26 degrees; gear must then be down and locked to silence warning system.
LGEAR_011
Describe the secondary indicator for nose gear extension:
Nose gear verification is provided by an indicator on the forward pedestal. The indicator appears when the nose gear is fully extended and nose gear links are locked overcenter.
LGEAR_012
Recall where the brake temperatures are displayed?
- Brake temperatures are displayed on the First Officer’s Instrument Panel.
- The BRAKE TEMP gauge indicates hottest or selected brake temperature depending on the position of the Brake Temp Selector.
LGEAR_013
Recall when the Brake OVHT light illuminates:
The Brake OVHT light illuminates when brake temperature exceeds 305°C (88) / 540°C (90).
WARNING: If a 305°C (MD-88) temperature exists for approximately 5 minutes, wheel fuse plugs may activate and deflate the tires. Keep all personnel clear of main landing gear area.
