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Take off and landing distance

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The takeoff and landing distance for AI aircraft in FS2004 is much shorter than in real life. Is there a way to extend the amount of runway used or is the distance hard coded in the software? Any help is much appreciated.Jim H

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Hi Jim.Have you got add-on AI or are you using the default? Either way, the potential is there to adjust the braking distance, although caution is advised because if you adjust the brakes to lengthen the stopping distance, then you might a) prevent the planes from stopping soon enough to pick up a taxi node so that the plane can taxi off the runway, or :( on shorter runways, the plane might not stop in time before the end of the runway! I haven't tried it for AI but there's no reason to suggest that the brakes for both user- and AI-aircraft are not controlled by the [brakes] section of the aircraft.cfg file and are controlled by the line 'toe_brakes_scale =': higher figures mean more effective braking. The default 737 has this set at 0.882, so you could try adjusting this in each of the AI planes that need adjusting. Back up the original cfg file first though, just in case.;)

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The takeoff and landing distance for AI aircraft in FS2004 is much shorter than in real life. Is there a way to extend the amount of runway used or is the distance hard coded in the software? Any help is much appreciated.Jim H
Are you sure about the take off distance? Landing it should be because the brake. After landed AI aircrafts start brake immediately and in FS2004 that should be maximum breakRolling%20Eyes.gif So the plane slows down quite fastCorrect me if I'm wrong :D

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Are you sure about the take off distance? Landing it should be because the brake. After landed AI aircrafts start brake immediately and in FS2004 that should be maximum breakRolling%20Eyes.gif So the plane slows down quite fastCorrect me if I'm wrong :D
Take off and landing distance is affected by gross weight, I doubt AI aircraft calculate correct pax/cargo loads fuel for trips etc so they fly empty with zero fuel. Also as mentioned above real aircraft dont land with Max autobrake and Max reverse thrust unless absolutely necessary, AI just slam on the brakes, also on take off real aircraft use reduced thrust or FLEX whenever possible, AI blast of at TOGA thrust like the space shuttle.I switched off AI and default ATC years ago.

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The reason the AI planes seem to have such short stopping distances programed into the FDE of the aircraft is to allow for quick exit from the runway which improves AI traffic flow, thus reducing go around incidents. The FDE's of the AI aircraft are intentionally design that way. As stated by Microlight, you can change that if you wish, in the brake section of the aircraft cfg and further changes can be made in the airfile using a program called AirEd. As previously advised be sure to back up anything before you make changes. Again, as also previously, the AI spending more time on the runway will significantly increase traffic flow issues around all airports where said aircraft are landing. The take off distance is a much more delicate balance and making any modifications in that respect can actually destroy the planes ability to function properly. Some examples: will not be able to climb to altitude instructed by ATC and will not be able to attain the cruise altitude required by the associated flight plan; could be under powered and in attempting to land simply fall short of the runway representing a crash in which case the AI simply disappears. So my advice would be to just live with the short take off distance. I hope the helps some.Regards,Mel

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Thanks, guys.....all great responses. First, yes most of the aircraft I'm working with are AI, but since I fly mostly military aircraft, I use several 3rd party aircraft in AI mode. I've reconstructed an Air Force base when I was stationed in the 60's, and I'm attempting to make it as realistic as possible. B52's and KC135's just don't take off and land on the first 15% of the runway. I'm stilll pretty new at this, but I have greatly enjoyed learning more about how to tinker with everything to try and get it more like the real thing. Thanks again for your help.Jim H

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Thanks, guys.....all great responses. First, yes most of the aircraft I'm working with are AI, but since I fly mostly military aircraft, I use several 3rd party aircraft in AI mode. I've reconstructed an Air Force base when I was stationed in the 60's, and I'm attempting to make it as realistic as possible. B52's and KC135's just don't take off and land on the first 15% of the runway. I'm stilll pretty new at this, but I have greatly enjoyed learning more about how to tinker with everything to try and get it more like the real thing. Thanks again for your help.Jim H
You can adjust the engine thrust and weight in order manipulate the takeoff distance, but I would start with the weight. The only weight that the AI reads is the empty_weight in the aircraft.cfg file. That is why your AI planes use so little runway on takeoff. The flight dynamics are that of an empty aircraft. Adjust the empty weight of the AI aircraft up towards a more realistic flying weight if you want to make the plane behave more realistically.

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My general approach:1. Adjust the empty weight until the approach speed is realistic.2. Adjust the reverse and brake values until the landing roll is OK (reverse is in the General Engine Data section).3. Adjust the engine power until the takeoff roll is OK.4. Adjust the drag scalars (in the fine tuning section) until the flight behavior is OK. parasite_drag_scalar= induced_drag_scalar=(1.0 is unchanged, 2.0 is twice normal, etc.)Other things that can affect takeoffs is the no flaps stall speed, and the wingspan can affect many parts of the flight envelope. Note that wingspan is used as a radius value in FSX, and so should be close to realistic.Hope this helps,

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Many thanks to all the responses. I've adjusted the takeoff empty weight on my aircraft and that did the trick. I may continue t o"tinker" with the setting a little more, but it now takes about 3/4 of the runway to take off in a B52 or KC135 and about the same for landing. Much more realistic than before. Again, I really appreciate the help. Does anyone know of any documentation that discusses the different parameters for the air.cfg files?Jim H

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The Aircraft Container SDK has some info, but not all. And much of it is like:toe_brake_scalar: scalar for the toe brakes. Not too helpful...

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Thanks for all the info. I'm okay with my AI but do have a payware 747-200/300 that has realistic seeming take-off performance but stops far too easily and quickly so the info on here will help me adjust it. One of those little things that annoy but wasn't a big enough deal for me to ask. :smile:Following your advice I adjusted the toe brake scalar (also decreased autobrake) but other than an entry that said reverse is available (reverse=1) I couldn't find any actual values for it - I checked a number of different aircraft.cfg files to see if they had anything else. Can anyone point me to where that might be?

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Hi,Sure.The line is:min_throttle_limit=-0.42If this was set to 0 then you would have no reverse thrust. A negative number gives you reverse thrust. This will control how fast the plane slows down early in its landing roll (before the brakes come on).Hope this helps,

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