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Guest julio917

How Can I Increase Max Speed On A/c?

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I've been looking online on how to modify the .cfg file for the Captain Sim 727. During cruise the max speed I can obtain is .69 mach where is I've read specs stating it reaches .81. what part of the .cfg file do I have to modify to achieve this?

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I've been looking online on how to modify the .cfg file for the Captain Sim 727. During cruise the max speed I can obtain is .69 mach where is I've read specs stating it reaches .81. what part of the .cfg file do I have to modify to achieve this?
The question you should be asking is "what flight level should I be at to obtain the rated speed?" To which the correct answer is "it depends..."1) on total weight: number of crew, number of pax, cargo, fuel on board, etc.2) temperature3) humidity4) winds aloftThe figure you're citing is likely the max achievable with minimum fuel, no pax, no cargo and minimum crew...

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The question you should be asking is "what flight level should I be at to obtain the rated speed?" To which the correct answer is "it depends..."1) on total weight: number of crew, number of pax, cargo, fuel on board, etc.2) temperature3) humidity4) winds aloftThe figure you're citing is likely the max achievable with minimum fuel, no pax, no cargo and minimum crew...
Which I thought was a factor as well, until I tried that, I could be a FL260 or FL410, heavy or empty and it will not exeed .69.

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Find the line in the cfg that reads:

[jet_engine]thrust_scalar = 1.0

Then change it to a value greater than 1. A value of 2.0 should double your thrust, and a value of 1.1 should be a 10% increase in thust.Like wise on prop planes find:

[piston_engine]power_scalar = 1.0

Or:

[propeller]thrust_scalar = 1.0

If you change the power scalar it will alter how the sound file is interpreted, so you typically get full throttle audio comming in too soon if you increase it, or not at all if you decrease it. If you alter thrust scalar it won't affect the engine sound, so that's an easy way to get more go from a prop plane.You can also mess with these other piston engine values, but again it will mess with the engine sounds a bit. If you make small changes its not noticeable though. RPM is a good one to play with, which will increase your max RPM, therefore making more power available. I suppose in real life if you're increasing max RPM the engine would be re-tuned to move the torque curve higher, but even without that you'll still make more power with a higher RPM. If you want to bore out your cylinders a bit increase your cylinder_displacement, which will give you more power at any given manifold pressure setting. On engines with a turbo you can increase the max_design_mp for higher boost levels. Changing max_rated_hp will not affect the engines power output from what I have seen, it will only change the way the engine sound scales with the power figures.

[piston_engine]power_scalar = 1.0							  //Piston power scalarcylinder_displacement= 90.3					 //Cubic inches per cylindercompression_ratio= 8.7						  //Compression rationumber_of_cylinders=6						   //Number of cylindersmax_rated_rpm= 2700							 //Max rated RPMmax_rated_hp= 300							   //Max rated HPfuel_metering_type= 0						   //0=Fuel Injected, 1=Gravity Carburetor, 2=Aerobatic Carburetorcooling_type= 0								 //0=Cooling type Air, 1=Cooling type Liquidnormalized_starter_torque= 0.3				  //Starter torque factorturbocharged= 0								 //Is it turbocharged? 0=FALSE, 1=TRUEmax_design_mp= 30							   //Max design manifold pressure, (inHg)min_design_mp= 15							   //Min design manifold pressure, (inHg)

Then there's a few more in the prop section which I've played with, such as prop diameter. If increasing the engines power it would be wise to increase propeller_diameter to absorb that power, otherwise the engine tends to over-rev a bit.

[propeller]thrust_scalar = 1.0							 //Propeller thrust scalarpropeller_type= 0							   //0=Constant Speed, 1=Fixed Pitchpropeller_diameter= 6.2						 //Propeller Diameter, (feet)propeller_blades= 3							 //Number of propeller blades

What I've done to some planes like my SF-260 to mimick a custom engine setup is increase the displacement a bit to get more power at all settings, add a couple hundred RPM to get more power above the stock RPM, and then increase prop diameter proportionatly to take advantage of the added power. The only down side is the full throttle sound file kicks in sooner, depending on how much power was added, but that's fine with me.

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Which I thought was a factor as well, until I tried that, I could be a FL260 or FL410, heavy or empty and it will not exeed .69.
Also make sure your not flying with your speed brakes extended. :(

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Find the line in the cfg that reads:
[jet_engine]thrust_scalar = 1.0

Then change it to a value greater than 1. A value of 2.0 should double your thrust, and a value of 1.1 should be a 10% increase in thust.Like wise on prop planes find:

[piston_engine]power_scalar = 1.0

Or:

[propeller]thrust_scalar = 1.0

If you change the power scalar it will alter how the sound file is interpreted, so you typically get full throttle audio comming in too soon if you increase it, or not at all if you decrease it. If you alter thrust scalar it won't affect the engine sound, so that's an easy way to get more go from a prop plane.You can also mess with these other piston engine values, but again it will mess with the engine sounds a bit. If you make small changes its not noticeable though. RPM is a good one to play with, which will increase your max RPM, therefore making more power available. I suppose in real life if you're increasing max RPM the engine would be re-tuned to move the torque curve higher, but even without that you'll still make more power with a higher RPM. If you want to bore out your cylinders a bit increase your cylinder_displacement, which will give you more power at any given manifold pressure setting. On engines with a turbo you can increase the max_design_mp for higher boost levels. Changing max_rated_hp will not affect the engines power output from what I have seen, it will only change the way the engine sound scales with the power figures.

[piston_engine]power_scalar = 1.0							  //Piston power scalarcylinder_displacement= 90.3					 //Cubic inches per cylindercompression_ratio= 8.7						  //Compression rationumber_of_cylinders=6						   //Number of cylindersmax_rated_rpm= 2700							 //Max rated RPMmax_rated_hp= 300							   //Max rated HPfuel_metering_type= 0						   //0=Fuel Injected, 1=Gravity Carburetor, 2=Aerobatic Carburetorcooling_type= 0								 //0=Cooling type Air, 1=Cooling type Liquidnormalized_starter_torque= 0.3				  //Starter torque factorturbocharged= 0								 //Is it turbocharged? 0=FALSE, 1=TRUEmax_design_mp= 30							   //Max design manifold pressure, (inHg)min_design_mp= 15							   //Min design manifold pressure, (inHg)

Then there's a few more in the prop section which I've played with, such as prop diameter. If increasing the engines power it would be wise to increase propeller_diameter to absorb that power, otherwise the engine tends to over-rev a bit.

[propeller]thrust_scalar = 1.0							 //Propeller thrust scalarpropeller_type= 0							   //0=Constant Speed, 1=Fixed Pitchpropeller_diameter= 6.2						 //Propeller Diameter, (feet)propeller_blades= 3							 //Number of propeller blades

What I've done to some planes like my SF-260 to mimick a custom engine setup is increase the displacement a bit to get more power at all settings, add a couple hundred RPM to get more power above the stock RPM, and then increase prop diameter proportionatly to take advantage of the added power. The only down side is the full throttle sound file kicks in sooner, depending on how much power was added, but that's fine with me.

That did it! Thank you very much. At first putting 2.0, made the a/c depart like an F16, I later placed at 1.3 and thrust is good. Thanks again!

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