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Guest pecrowther

Reverse Thrust

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What parameters do I have to change to create significant reverse thrust for a jet? Significant = enough to cause the jet to back up.Thanks,Phil

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In the aircraft.cfg:TurbineEngineData Sectionreverser_available = 1In the .air file:Tables 313 and 1522.See the B737 files for parameters.

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Looks like the max value for Table 313 (Reverse Thrust) is only 100 and sent the Min_Throttle_Percent to -100. No luck.Thanks,Phil

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Hi Phil,I also tried that :-)... Same result as you .. no luck.Obviously FS9 has some built-in criteria at which it allows the Reverser to engage (= throttle position negative).Like you cannot set a negative throttle position when an aircraft is in the air.First I thought it had something to do with the "aircraft" being able to float, but that cannot be the reason since the default Cessna Caravan Amphi works OK with reverse thrust (if you add the reverser_available=1 to its aircraft.cfg).So it must be something else that's blocking a negative throttle position.Could it have anything to do with Gear, or something like that ??Cheers, Rob

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Be sure you set throttle to zero by pressing the F1 key before activating the F2 Reversers.In the GeneralEngineData section of the aircraft.cfg, change this parameter to a higher value like the value shown. This will reverse the B777 at a decent rate.min_throttle_limit = -0.75;This may not be realistic for large jets, but it works. Be aware that this change will also cause a bit of a surge forward when coming out of reversers. You may experiment with lower values. I like about 50% for my Dash 7.

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>>>>Looks like the max value for Table 313 (Reverse Thrust) is only 100 and sent the Min_Throttle_Percent to -100. No luck.<<<

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Thanks all,Yes, I meant "min_throttle_limit".One possible complication is that I am trying to get a ship to go backwards rather than a plane. However, the weight of the ship is about the same as a 747. I have increased the parasitic drag and have increased the thrust accordingly. If reverse thrust increases in relation to total thrust, it should move backwards.As to the "squat switch", I have left a single invisible retractable wheel on the ship (so I can use the "G" key), and which I assume starts out down. While this would normally not set a squat switch, it sounds as though it does on the Caravan Amphibian.Is there a value for reverser extension/retraction that I may have inadvertently changed?Otherwise, it sounds like I am going to have to put a 747 on floats and see what happens.Phil

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Phil,I had no idea you were modeling a ship. That complicates matters. Some of the references you and Rob made in your replies are now clear to me. The problem with reverse thrust being inop lies in the contact point types (with regard to the surface type in FS9), and possibly the engine types.Your single Type 1 contact point didn

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Doug,I really appreciate your taking the time to check those things. A couple of retired Navy vets asked if I could look into adding reverse power to the ship - just like a real one. I'm not sure if I could stand to try creating another prop version. I spent about a month trying to get one to work, but it would either sit there forever or go too fast, or both. There are two parameters to worry about - prop and power. At least with the jet, I have only power.(The prop version was not a total loss, since I used it for the AI model. The jet sound was too much and I was getting four smoke columns with the jet. I never did figure that one out.)Unless and until I resolve this, it looks like everyone will just have to call a tug!Thanks,Philp.s. I am having to fix the speed indicator on the ship. It is off by a factor of about 2. (You can see the true speed using the "tool tip".) So the ship is going a bit faster than it should. But it does create a neat wake!

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I am curious if "Pushback" works. :-)Have you tried increasing min_throttle_limit = -0.75 or greater, -1.00?

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>>>>I'm not sure if I could stand to try creating another prop version. I spent about a month trying to get one to work, but it would either sit there forever or go too fast, or both. There are two parameters to worry about - prop and power. At least with the jet, I have only power.<<<>>>I am having to fix the speed indicator on the ship. It is off by a factor of about 2. (You can see the true speed using the "tool tip".) So the ship is going a bit faster than it should.<<<>>> I am curious if "Pushback" works. Have you tried increasing min_throttle_limit = -0.75 or greater, -1.00?<<<

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Apparently pushback does work for the floating ship on the water.Phil

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