Powerplant (Spinny boi) Flashcards
How many FADEC’s does each engine have?
Two, A and B.
How many stages is in the power section of the turbine?
14
What is the GMAD and what does it provide?
Gear Mounded Accessory Drive and is connected to the Propeller gear box and provides power to the hydraulics, generators, scavenge pump and high pressure oil pump and propeller pitch control unit.
How is NP controlled by the FADEC?
Propeller pitch angle and fuel flow
What is the ‘safe condition’ for moving power levers below flight idle?
<145KTAS and WoW on all 3 wheels
When the green B is displayed in the HP gauge what is the blade angle?
23’ to 10.5’
When above 155kTAS and the power levers are inadvertently moved below flight idle what happens?
Blade angle interlock limits the blade angle to 23’ to prevent catastrophic overspeed. When slowing below 155KTAS with PLA no lower than flight idle the FADEC will schedule the blade angle down below 23’ and allow the engine to enter ground range.
What is the delay for an outboard and inboard engine to auto feather?
Outboard engine will always feather immediately, and inboard engine will feather after a 2 second delay provided the aircraft is below 15,500ft and the other engines are operating normally. Otherwise it will windmill at 100% RPM
If there is a suspected flameout, what does the FADEC do?
initially tries to maintain idle, it will then energise the igniters and monitor for a relight. If NG decreases below 56% it will then shut the engine down.
When will the MC command an auto shutdown?
With all the power levers at an equal PLA for 5 seconds and >1100hp difference between engines with NG stable
When will the FADEC automatically stop a start sequence?
No light up, flameout and RPM stagnation.
What is a design feature of the engine that reduces the chances of internal engine icing reference fuel?
Fuel is used to cool engine return oil and heat up the fuel to reduce the possibility of engine icing
What is the oil quantity of the engines?
12GAL
Why is there a minimum time for engine restart if shutdown inflight?
Oil pooling occurs in the engine if the engine is windmilling and the fire handle is not pulled. The scavenge pump does not operate efficiently in transient NG values
what happens to the engine during start with reference to bleed air?
During start bleed air is vented into the nacelle from the 10th stage compressor until the gas generator is at idle speed. It then switched from the 10th stage to the 14th for normal bleed air operations.
When in ground range and you move the power levers, what happens to the engine and propeller pitch angle to supply the demanded thrust?
In ground range the power levers control the propeller pitch and the engine is regulated to maintain a certain RPM.
When in reverse range and you move the power levers, what happens to the engine and propeller pitch angle to supply the demanded amount of reverse thrust?
The propeller blade angle is adjusted to maintain 101% RPM.
What does the STOP, do on the STOP START RUN switch?
Shuts off fuel at the engine, and turns off the main boost pump for the respective engine tank
When does the FADEC automatically stop and engine start?
No Light off, Flameout and stagnated start
What does pulling the fire hand do with reference to feathering the propeller?
It will run the independent aux feather pump
How many fire and overheat detection loop(s) does each engine have?
Two
Where are the overheat detection sensors located?
Monitors for bleed air leeks in the Nacelle, Wing, X-ship and underfloor heat of the bleed air system
What happens to the bleed air ducts when an overheat is detected?
The Fire/overheat detection system will close the F/ODS valve to isolate the duct. If the valve does not close you will receive BLD AIR LEAK NOT ISOL with a warning.
If two fire handles are pulled and you try to discharge extinguishing agent where is it routed?
To the engine which had the fire handle pulled last? If agent is required on another engine that engines fire handle must be reset then pulled again.
What happens when a fire handle is pulled?
All fluid is shut off from entering and exiting the engine. Fuel, Oil, Hydraulics, Bleed air and agent is now available and BAU commands the aux feather pump to operate for 20s to feather the propeller.
When does the engine switch from 10th stage bleed air to 14th stage bleed air to power the pneumatic systems?
It will switch to the 14th stage bleed air when engine HP is below 1000HP to keep the pressure at the required amount.
Which battery provides starting power through the essential DC bus for APU start?
Utility Battery
When doing an APU emergency start what F/ODS are not available you’d otherwise have?
Start indications, Auto shutdown and aural alarm are not available, comms (Visual/shouting) required with loadmaster.
