Landing Gear System Flashcards
MLG Shock Strut
2 stage nitrogen/oil strut that absobs the majority of force associated with landing
MLG Drag Strut/Actuator
Attached to MLG shock strut and extends and locks the gear for landings and retracts the gear in flight
MLG drag strut/actuator lock pin
Inserted by the ground crew at the junction of the actuator and shock strut to lock the gear in extended position when the aircraft is on the ground
Where are the MLG Gear Position switches located
mounted on the upper and lower section of the drag strut/actuator
What provides brake power
No. 3 hydraulic pump
what provides back-up brake power
electric motor hydraulic pump and an accumulator. The pump continuously recharges the accumulator
Pressure of Back up Brake System
2,000 psi
Capability of the Back up brake system
capable of holding the aircraft on a 10 deg slope at max alternate gross weight of 60,500 lbs
In the event of a leak in the flight control portion of the Hydraulic No. 3 the Back up brake system is capable of providing ___
a minimum of 5 brake applications within a 15 minute time frame after engagement of the system if the leak occurred within 1.25 hours of system engagement
NLG Drag Strut/Actuator
Attached to the shock strut and the aircraft frame, and is hydraulically powered to extend and lock the gear and to retract the gear
NLG Ground Lock Safety Pin Assembly
Prevents accidental retraction on the ground. Attached to the cable assembly that runs to the drag strut/actuator lock pin lever
Nose Hike Nitrogen Chamber
Used to raise the nose 15 inches to facilitate shipboard towing within the hangar deck.
NLG Out of Range switch
Mounted on the power steering collar to disable the steering commands if steering angle exceeds 75 degrees from center
What provides power for the Power Steering System
Hydraulic System No. 3
Nosewheel Steering (NWS) 3 modes of operation
- Power Steering2. Nosewheel Lock3. Full Swivel (Power Steering Off)
What must occur for power steering to be activated
both main gear or nose gear is weight on wheels, 20 sec have elapsed, and no steering failures exist
Nosewheel steering displacement
70 degrees
Max airspeed for gear extension or retraction
140 KCAS
Max airspeed with gear extension
150 KCAS
Max VTOL/CONV mode touchdown rate
720 fpm for gross weight less than 46,000 lbs and 600 fpm for gross weight greater than 46,000 lbs
When is the landing gear warning low altitude mode armed
when the gear is retracted, nacelles are greater than 70 degrees, and aircraft exceed 500 ft/min rate of climb
When is the landing gear warning triggered in low altitude mode
If rate of climb drops below 200 ft/min for 3 sec below 240 ft AGL.
When is the landing gear warning high altitude mode armed
Above 240 ft AGL or nacelles lower than 70 degrees
When is the landing gear warning triggered in high altitude mode
When aircraft descends below 200 ft AGL, nacelles are greater than 70 degrees, and the gear is not down and locked
Which electrical bus provides power for gear extension and retraction controls and gear position indicators
No. 1 DC Bus
Static ground wires
mounted between the two wheels on each Landing Gear Shock Strut to discharge the aircraft’s static electricity
What happens when both pilots apply brake pressure simultaneously
The system responds only to the pilot applying the higher pressure
When is backup break power used most often
For spotting on the ship or hangar decks when the APU is not running
The electric motor for the backup brake is powered by which bus
The unswitched battery bus, so failure to turn it off can cause the battery to drain
Where is the Emergency Extension Nitrogen Bottle and Gauge located
In the aft right sponson
When might an abnormal retraction be necessary
- The control handle down lock solenoid fails to release the mechanical lock 2. there is a WOW switch failureIn either case use the DOWN LOCK ORIDE
Landing gear handle position for emergency extension
Emergency extension takes place regardless of the gear handle position
What triggers LG DN A/S EXCEEDED Caution
Landing gear is down and the airspeed exceeds 140 KCAS
Procedure for LG DN A/S EXCEEDED Caution
If 150 KCAS is exceeded:1. Landing Gear - Remain Down2. Land as soon as practical
What triggers NOSEWHL NOT CNTRD Caution
One of the following conditions occurred during gear retraction:1. Nosewheel not centered2. Nosewheel position is unknown and the nosewheel actuator failed3. There is an actuator fault
Procedure for NOSEWHL NOT CNTRD Caution
CAUTION: Do not attempt to raise the gear. If gear retraction is attempted without the nosewheel centered, major structural damage may occur.1. PFCS - ResetIf caution does not clear2. Land as soon as practical, vertical landing recommended
What triggers NOSEWHL STEER FAIL Caution
Nosewheel steering actuator has failed or nosewheel is beyond 75 degrees from center
What triggers LAND GEAR ABORT Advisory
Landing gear has not successfully completed an up or down transition cycle within 30 +/-5 seconds
What triggers LANDING GEAR FAULT Advisory
The Landing Gear Control Unit has detected a BIT fault or the Landing Gear Control Solenoid Valve has failed overspeed caution and gear up warning tone may be inoperative. Or Landing gear has lost down lock. Hydraulic pressure is now continuously provided to landing gear actuators.
Procedure for LAND GEAR ABORT Advisory or LANDING GEAR FAULT Advisory
- Attempt to operate gear normallyIf unsafe gear indications 2. Landing Gear Fails to Extend - Execute
Procedure for LANDING GEAR FAULT Advisory if cause is lost down lock.
If landing gear is relocked1. Landing normallyIf landing gear fails to relock2. Landing gear fails to retract/extend - Execute
What triggers WOW DISAGREE Advisory
WOW switches disagree for more than 15 seconds
