Main Rotor Drive System Flashcards
What drives the Main Gearbox (MGB) oil cooler fan?
Tail take-off pinion
How many input drive assemblies does the Main Gearbox (MGB) casing contain?
Two
Name one purpose of the main gear train
To provide a reliable, efficient means of reducing high engine input speeds
How many input freewheels are fitted in the Main Gearbox (MGB)?
Two
Which components are driven by the Accessory Gearbox (AGB)?
The No. 1 and No. 2 AC generators, the No. 1 and No. 2 hydraulic pumps and the Main Gearbox (MGB) oil pump
Why between the left and right accessory freewheels is there a 69 RPM speed difference when both engines are driving in “FLY”?
Ensures constant positive accessory drive from the right side preventing the engines from “hunting”
What is the purpose of having a different gear ratio for the left and right accessory through-shaft gears?
To ensure the right rotates faster than the left to prevent the engines hunting, causing driveshaft chatter
What is fitted to the Accessory Gearbox (AGB) to provide the Cockpit Display System (CDS) and Engine Electronic Control Units (EECU) with rotor speed data (NR)?
A mechanically driven tachometer generator
The actuator and a freewheel controller are two primary components of which of the following?
The Accessory (ACC) drive actuator
Where is the ENG 1 DRIVE push switch control situated which controls the Accessory (ACC) drive actuator?
Right of the engine fire panel section of the overhead console
What condition is the accessory/main drive actuator in when the engine 1 drive [ENG 1 DRIVE] Light Emitting Diode (LED) caption indicates solid black and power is connected to the aircraft?
In transition
After engine shutdown, how much time must elapse before checking the Main Gearbox (MGB) oil level?
At least 5 minutes
Where is the Main Gearbox (MGB) oil temperature bulb located?
MGB oil filter assembly
The Main Gearbox (MGB) filter blockage indicator will pop up when the filter element becomes blocked to indicate what colour?
Red
What is the purpose of the thermal lock fitted on the Main Gearbox (MGB) oil filter assembly?
To prevent operation of the blockage indicator at low oil temperatures
How many air exhausts are contained within the Main Gearbox (MGB) oil cooler fan housing?
Three
In the Main Gearbox (MGB), through what is the majority of the hot oil cooler exhaust expelled?
The air management duct
With both engines running in FLY how are the accessories being driven?
By the right accessory through-shaft only
Which Warnings, Cautions and Advisories (WCA) indicator illuminates when the Main Gearbox Oil Pressure (MGBOP) initially falls below 2.3 bar?
Yellow [MGB LOPRESS] caution
