Blade Fold Wing Stow Flashcards
How long does the BFWS sequence take
90 seconds to stow, 60 seconds to unstow the wing and 30 seconds to unfold the blades
RPU
Rotor Positioning Unit - A hydraulically operated drive speed reduction unit, mounted on the Midwing Gearbox (MWGB). Its primary purpose is to rotate the proprotor blades to the desired position for BFWS operations.
RPU Proximity Sensors
Provide a LOCKED, INDEX, or FLY position signal to the Mission Computers during the selected BFWS sequence.
Slip Ring Assembly
Provides an electrical interface between the stationary nacelle and the rotating electrical components mounted on the proprotor assembly
Which blade does not fold
The red blade
Stow Ring
Fastens the wing to the fuselage. It allows the wing to rotate to the stowed position.
What is the primary indication that the wing is in flight ready or full stow condition
Lockpins and 57 degree switches; 4 wing lockpins are reequired to be engaged in the flight ready position. There are 2 lockpin indicators on each side of the fuselage
Lockpin indications for locked and unlocked
Unlocked = the checkerboard black and white patternLocked = solid black
Conducting BFWS above __ may damage the Blade Fold Planetary Assembly
45 kts
Ship Motion Limitations
Should not exceed 3 degrees pitch and 15 degrees roll when executing BFWS sequence
Temperature below ___BFWS will be sluggish taking __ minutes, and below ___ will take ___ minutes
-29 degrees C, 3 minutes-40 degrees , 8 minutes
Purpose of the BFWS
to reduce the overall dimensions of the aircraft for shipboard operations and hangar storage, and to provide access for maintenance.
5 BFWS Positions
- Flight Ready2. Maintenance3. Fold Horizontal4. Fold Vertical 5. Fully Stowed
6 BFWS Maintenance Positions
- Rotor Lock2. Fold Horizontal 3. Fold Vertical4. Maintenance Red5. Maintenance White6. Maintenance Green
Resolver Select Key on the BFWS SYST Layer
Monoplane sensors determine the rotor azimuth and speed for the BFWS. This key is used to select either the left or right resolver in the event of ROTOR POSITION UNKNOWN or ROTOR POSITION RESOLVER DISAGREE