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B1900C Question

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Where can I find data on the use of high/low idle? I remember a couple of years ago either PC Pilot or Computer Pilot had an article on the B1900D on the proper approach for the use of the the idle throtle. I'm just getting back into flight simulation again and I do have the B1900C and D, being able to use them properly would make there flights more enjoyable.ThanksTom

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I assume low idle would be used when the prop is feathered and not taking much torque to keep it turning and high for when the prop is pitched as it would tend to slow the engine down so would need a comensation for that.A guess I know but sure someone will put me right and you'll then have the right answer lol.John Ellison

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I assume low idle would be used when the prop is feathered and not taking much torque to keep it turning and high for when the prop is pitched as it would tend to slow the engine down so would need a comensation for that.A guess I know but sure someone will put me right and you'll then have the right answer lol.John Ellison
John thank you. The answer that I am really looking for is when in flight, what position should high/low idle set to while in cruise.Thanks againtom

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You wouldn't be at idle in cruise surely! In descent maybe but that would be flight idle so high idle then. Hope you find like I did that it flies really beautifully in any case - bit wandery on initial nav heading but I found if you line it up first then no problem.John Ellison

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The purpose of the flight idle position is to reduce the delay in engine response to power commands due to the inherent delay in turbine spool-up. There is more delay in a power change increase from ground idle than from flight idle.Flight idle is always used to my knowledge in any phase while in the air even descent and landing so a quick power increase response can be obtained for an aborted landing (go-around). Another use is to get a quick response for terrain obstacle avoidance or getting out of aircraft conflict paths by climbing out quickly.Flight idle is set when entering the active runway (unless doing a taxi-back) and ground idle is set on vacating it. There is less of a chance of engine failure at flight idle or above to to various reasons such as precipitation entering the compressors.Ground idle is used for taxiing to save breaks and fuel. A quick performance increase is usually not required on the ground.AFAIK pure jets (no prop) do not require a ground idle/flight idle control because there is no prop drag contributing to spool up delay. Jets are always at a flight idle condition. If a jet is taxiing to fast the pilot will engage "idle reverse" which means the reverse buckets are opened but with idle thrust supplying the drag. This is instead of applying brakes frequently. Some jet policies in certain situations also taxi with less than the amount of the full engine complement to save fuel and avoid too much engine total power during taxi.Finally remember to have your prop condition (rpm) at the highest rpm (full rpm) position. It can function as a speed brake when expediting an approach decreasing to flight idle and needing to slow down as you get near the threshold and you are also set to apply maximum engine power if a go-around is required.

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The purpose of the flight idle position is to reduce the delay in engine response to power commands due to the inherent delay in turbine spool-up. There is more delay in a power change increase from ground idle than from flight idle.Flight idle is always used to my knowledge in any phase while in the air even descent and landing so a quick power increase response can be obtained for an aborted landing (go-around). Another use is to get a quick response for terrain obstacle avoidance or getting out of aircraft conflict paths by climbing out quickly.Flight idle is set when entering the active runway (unless doing a taxi-back) and ground idle is set on vacating it. There is less of a chance of engine failure at flight idle or above to to various reasons such as precipitation entering the compressors.Ground idle is used for taxiing to save breaks and fuel. A quick performance increase is usually not required on the ground.AFAIK pure jets (no prop) do not require a ground idle/flight idle control because there is no prop drag contributing to spool up delay. Jets are always at a flight idle condition. If a jet is taxiing to fast the pilot will engage "idle reverse" which means the reverse buckets are opened but with idle thrust supplying the drag. This is instead of applying brakes frequently. Some jet policies in certain situations also taxi with less than the amount of the full engine complement to save fuel and avoid too much engine total power during taxi.Finally remember to have your prop condition (rpm) at the highest rpm (full rpm) position. It can function as a speed brake when expediting an approach decreasing to flight idle and needing to slow down as you get near the threshold and you are also set to apply maximum engine power if a go-around is required.
Ron,Thanks for the level of detail in your reply. I printed out your reply and will try implementing it this weeked.Thanks againTom

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