Emergency Power Lever ?

[scottb613 1,188]

Hi Folks,

 

Just a generic question on the use of Emergency Power Lever on the 208... What exactly does it do and when/how exactly would you use it - I get the in an "Emergency" part - LOL - more specifics please... This is the only plane I recall seeing one in and you can already over torque the engine just by slamming the throttle wide open... Is it implemented correctly in the FDE ???

 

Regards,
Scott

[crashdriver 1]

I did my systems report on this aiprlane back in college so I'm lucky enough to have the book.  This is straight from the AFM

 

"The EMERGENCY POWER Lever is connected through linkage to the manual override lever on the fuel control unit and governs fuel supply to the engine should a pneumatic malfunction occur in the fuel control unit. When the engine is operating, a failure of any pneumatic signal input to the fuel control unit will result in the fuel flow decreasing to minimum idle (about 48% Ng at sea level and increasing with altitude). The EMERGENCY POWER Lever allows the pilot to restore power in the event of such a failure. The EMERGENCY POWER Lever has NORMAL, IDLE, and MAX positions.

 

The NORMAL position is used for all normal engine operation when the fuel control unit is operating normally and engine power is selected by the power lever. The range from IDLE position to MAX governs engine power and is used when a pneumatic malfunction has occurred in the fuel control unit and the power lever is ineffective. A mechanical stop in the lever slot requiresthat the EMERGENCY POWER Lever be moved to the left to clear the stop before it can be moved from the NORMAL (full aft) position to the IDLE position.

 

NOTE

The knob on the EMERGENCY POWER Lever has crosshatching. The crosshatching is visible when the lever

is in MAX position. Also, the EMERGENCY POWER Lever is annunciated by a Red CAS message on the PFD

whenever it is unstowed from the NORMAL position with the ITT indications in either of the OFF or STRT modes.

These precautions are intended to preclude starting of the engine with the EMERGENCY POWER Lever inadvertently

placed in any position other than NORMAL.

 

CAUTION

•The EMERGENCY POWER Lever and its associated manual override system are considered to be an emergency system and should be used only in the event of a fuel control unit malfunction. When attempting a normal start, the pilot must ensure that the EMERGENCY POWER Lever is in the NORMAL (full aft) position; otherwise, an over

-temperature condition may result.

•When using the fuel control manual override system, engine response may be more rapid than when

using the power lever. Additional care is required during engine acceleration to avoid exceeding engine limitations.

 

Operation of the EMERGENCY POWER Lever is prohibited with the primary power lever out of the IDLE position. The EMERGENCY POWER Lever overrides normal fuel control functions and results in the direct operation of the fuel metering valve. The EMERGENCY POWER Lever will override the automatic fuel governing and engine acceleration scheduling controlled during normal operation by the primary power lever.

 

CAUTION

Inappropriate use of the EMERGENCY POWER Lever may adversely affect engine operation and durability.

Use of the EMERGENCY POWER Lever during normal operation of the power lever may result in engine

surges, or exceeding the ITT, Ng, and torque limits."