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Changing when afterburner sets in?


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I have a fair share of military jets in my FS hangar now , and of course most military jets have afterburners. Most addon aircraft simply have the afterburner kick in when the throttle advances far enough but unfortunately there is a wide discrepancy between planes as to when the afterburner sets in. Some have it set in after about 90% throttle, whereas in a couple it sets in literally after the 40% mark, which leaves little room for fine throttle adjustments!


Some aircraft have an "AB" light in the cockpit but not all do, and often I have to switch to spot view to see if there's any flames coming out my tailpipe, which can be a very annoying.


So is there anyway of changing the afterburner settings in the Aircraft cfg file?

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I took this section of the aircraft.cfg from my F-101 Voodoo.



//®F-101C: PW J57-P13 mil 10,200 lbs, wet 15,000 lbs (ratio 1.4710)

//F-101B : PW J57-P55 mil 11,990 lbs, wet 16,900 lbs (ratio 1.4095)

fuel_flow_gain=0.003 //0.002

inlet_area=9.9 //6.4


static_thrust=11990 //14880


afterburner_throttle_threshold =0.8


ThrustSpecificFuelConsumption = 0.77

AfterBurnThrustSpecificFuelConsumption = 1.8


The 0.8 means the A/B will kick in at 80% thrust levers.

Still thinking about a new flightsim only computer!  ✈️

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Something else to pay attention to is the entries in the plane's .air file. First and foremost, they actually have to be present, second, they must be correct, or at least relatively so.


In Record 1501, line 7 there's an entry Afterburner= and it must be TRUE(1). If it's not, it must be changed to that.

In record 1521 Engine Reheat Available= it must be True(1) as well.

Finally, there must be a Record 1524 Turbine Reheat Thrust Factor vs Mach Number. It's a graph, and you can adjust it if you need to. I recommend leaving it though. Unless, of course, you're familiar with how-to adjust the graphs in a .air file, and which way to adjust which points to make to better than it is.


If any of those records are missing, go to an aircraft's .air file that has a good afterburner, and copy them over to the target plane's .air file. examples of planes *I* know for sure have good entries are Dino's T-45, and his F-14. If those records I listed aren't present, the plane's afterburner may LOOK like it's working properly, with flames shooting out the tailpipes and so forth, but you won't get the extra thrust, and correct fuel consumption.


Finally, the setting Zippy listed in his example works to set the throttle level where the AB's kick in, but you should also do a little research, and get the proper AfterBurnThrustSpecificFuelConsumption = entry. In his example, it's 1.8, which means that the AB's burn fuel at 1.8Xnormal engine fuel use. About right for the older plane engines. Newer planes have somewhat better consumption. Not necessarily a LOT better, but a little. Like the F/A-18C has a setting of 1.75. A little better but not much. Afterburners just suck gas like mad. It's just inherent in their basic design. After all, you're pouring a LOT of fuel into the final engine stage, so you use a lot of gas in AB.


Good luck!



Had a thought...then there was the smell of something burning, and sparks, and then a big fire, and then the lights went out! I guess I better not do that again!

Sgt, USMC, 10 years proud service, Inactive reserve now :D

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