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On a photo of the Quadrant of a Kodiak Quest 100 there was an additional red lever to the left of the throttle (black handle) labeled with "MAX EMR PWR". Can anyone explain what what this means and what the corresponding lever is used for?

Picture by Jeff Berlin on flyingmag.com

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    $\begingroup$ FYI, it isn't the "MAX EMR PWR" lever, it is the "EMR PWR" lever, with two positions: MAX, and NORMAL. $\endgroup$ Aug 12 at 21:09
  • $\begingroup$ It engages the afterburners. $\endgroup$
    – Mark
    Aug 14 at 18:48
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There is already a great answer quoting from the aircraft flight manual, but I thought I would offer some additional perspective. I'm not qualified in the Kodiak, but both the T-34C and C-208 have versions of the venerable Pratt and Whitney PT6 turbine engine, and both have Emergency Power Levers like this in case the Fuel Control Unit (FCU) fails.

Older (non-FADEC) turbine engine FCUs are electro mechanical, and meter fuel according to several inputs; typically RPM, turbine temperature, demand, (per power lever position) and probably a pressure sensor somewhere. With a failure of the FCU the engine will still run, but the metering function no longer works and the RPM will roll back to idle.

This is when the Emergency Power Lever comes into play: Once engaged the EPL bypasses the FCU and gives you manual control over a valve to add fuel to the engine to increase or decrease power output. However, without the other sensor inputs you lose the governing protection of the FCU. Instead of the power lever being just one input to be considered by the FCU to change a power setting, you are now directly controlling the fuel flow going to the manifold.

The way it was explained to me was to imagine your car's carburetor or computer controlled fuel injection system failing: Instead of venturis, needle valves, jets, etc. keeping a uniform fuel mist flowing into the cylinders, you are now keeping it running down the road by carefully and slowly pouring gas from a spouted measuring cup directly into the intake manifold.

Needless to say you must be very careful using EPL to dump raw fuel into the burner like this or you can easily overtorque the engine or toast the turbine section. In Navy flight training they had us fly an approach in the simulator using the EPL and it was VERY sensitive. You really had to keep an eye on the max turbine temperature and move the EPL very gingerly to avoid exceeding limits.

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    $\begingroup$ pouring fuel from a measuring cup into the intake manifold sounds like a comedy skit. Someone should do that. Bonus points if it's on a plane. $\endgroup$
    – user253751
    Aug 13 at 11:44
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    $\begingroup$ In high school a friend of mine had the throttle linkage on his old Nova break. He tied his shoe laces together, tied it so the throttle lever on the carburetor, threaded it through the firewall, and used a pull string throttle to get home! $\endgroup$ Aug 13 at 15:32
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    $\begingroup$ Oh good, a Nova is not a type of plane $\endgroup$
    – user253751
    Aug 13 at 15:57
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    $\begingroup$ I knew exactly what you were talking about. $\endgroup$
    – FreeMan
    Aug 13 at 17:23
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    $\begingroup$ I heard it said that in olden days bush pilots with a total fuel failure could rig up a pipe from the fuel tank ending in front of the air intake of an engine, such that the intake would suck in a fuel air mix like a carburetor. No control but it might get you home $\endgroup$ Aug 13 at 19:05
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From the Kodiak's flight manual:

EMERGENCY POWER LEVER

The emergency power lever is connected, through linkages, to the manual override lever on the fuel control unit [FCU] and allows manual governing of the engine fuel flow should a malfunction occur in the fuel control unit's pneumatic governing system.

The lever (once out of its safety stop) can be placed anywhere between normal and maximum (the word "MAX" shown) for manual fuel flow control, since an FCU failure would limit the engine to only idle fuel flow (approx. 48% Ng).

Since it's an override, once activated the power lever would be placed in idle, and the power controlled using the EMR PWR lever instead (flight manual § 3-15 ENGINE EMERGENCIES).


Consult your AFM; do not use for flight.

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