Flight Model Tweaks

  • Greetings All,

    I am looking for a way to tweak roll/pitch response and ground effect in some of the jets. I fly real world jets and I have light, medium and heavy experience. I am current and qualified in the Gulfstream 5/550. I am looking to recreate the feel and ground effect I experience when flying real world. Though this is also impacted by sim control setup, I find some jets, like the Lear 45 to be just a tad bit sensitive in pitch and roll. In most jets I've flown, the yoke is rigid due to artificial feel springs and cartridges.


    Roll and pitch rates are more sluggish during takeoff and approach/landing. In other words, the yoke has a heavy feel to it.

    The aircraft is stable/more resistant to input. On approach in gusty winds, you will find yourself doing what I call yoke cardio. You will have to put in large inputs to counter the aircraft's rolling and pitching moments. In essence, there is a slight delay in control response. Flying straight and level, I can quickly put in 45 degrees of yoke left and right and the plane will hardly move. This is why on gusty/bumpy approaches, you will see a lot of quick yoke movements and little aircraft response. I've demonstrated this to new guys during air refueling. They would close in on the tanker furiously pumping the yoke all around and back and forth. By the time they are in the contact position and plugged, they are so wore out from cardio that they fall off the boom quickly. That's when I take the jet. Back out to 300ft. I then have them watch and rock the yoke 45 degrees left and right and show them that the jet barely moves. I tell them the jet takes time to respond. I drop my armrests and demonstrate how I can close on the tanker using finger tips and wrist. I use small inputs, leaving them in until the jet responds and adjust. I fly to the contact position without yoke pumping cardio/PIO. So I am looking for a way to adjust the pitch and roll input in the flight model to simulate more stability/resistance to input.


    Last thing I would like to adjust is the ground effect. In a nut shell, ground effect is about a 200 to 300 feet per minute decrease of sink rate in jets. Should start happening at half of the jet's wing span. So for me, 93.6ft is my wingspan, effect starts around 45ft. So lets look at the typical approach in a jet(MD80/737). Normally, you are looking at a sink of about 700 to 800 feet per minute on a 3 degree glide. The text book procedure, similar to most, is to start a flare at the 20ft call out. At 20ft, you pull power to reach idle by wheel touch down. You add 2 to 3 degrees to your current pitch and hold it through the flare. The aircraft will touch down close to your aimpoint about 1000ft down the runway. Here is the approach with ground effect. The aircraft is trimmed to the approach with a natural tendency to stay on glide path requiring slight pitch corrections. As you start to enter ground effect, the nose will want to drop, requiring some slight back pressure on the yoke. If your aircraft's procedure is to cross the threshold at VREF, you will require a little more back pressure as the speed you are carrying bleeds off(I.E. bleeding off wind additives). For each 5 knots of speed change, the aircraft pitch will change about 1 degree to maintain glide path. At your flare height, you add in 2 to 3 degrees to your current pitch and allow the jet to fly onto the runway. As you add your flare input, that back pressure will be maintained through touch down. You may have to add just a little tad more to maintain your attitude because the jet is losing speed in the flare. You start your power pull at the same flare height and should reach idle by the time the mains touch. Your touch down should be 1000ft down, possibly 1200 to 1500 if you are one of those fight for greaser types. Of course, long bodied aircraft such as heavies will touch 1200 to 1500 down the runway due to using long body VASI/PAPI(2 pinks/2 whites) and higher flare height.

    In the past, I did adjust the left/right aerowing ground effect factor/scale. There seems to be 2 sections containing these and i'm unsure of which of the 2 sections to adjust.


    I know these adjustments are not for everyone, but I love when I get into a sim and the aircraft has the same feel and effect that I experience in the real aircraft. I feel right at home. Your help is appreciated.


    Rick

    • Official Post

    Hello Rick,


    The GroundEffectScale changes the height of the ground effect, lower value means the ground effect will only be effective really close to the ground whilst a higher value allows it to start earlier.

    The GroundEffectFactor is the overall intensity of the effect.


    At the moment the ground effect isn't final from my understanding, currently I don't know of any parameter which would affect the nose up or down tendency. Right now the nose tends to go up which I don't really like so we might introduce more parameters for this in the future.


    For you at the moment, I'd just go with the default factor and scale parameters for the main wings and the tail and adjust them to your liking.

  • Thanks Jet-Pack!,

    I did notice that aircraft tend to auto flare. Must be the effect you describe as the nose up tendency. If you guys ever need me to test things or have a question regarding aircraft behavior or performance, don't hesitate to hit me up. I've done a lot of check flights/shake downs for aircraft coming out of heavy depot maintenance. It's actually fun taking an aircraft up and putting her through her paces. You learn a lot about the aircraft and what it can. We do at all from accel time, stalls for stall system calibration and battery only ops to flight control checks and landing performance.


    Rick

  • Greetings All,

    I am looking for a way to tweak roll/pitch response and ground effect in some of the jets. I fly real world jets and I have light, medium and heavy experience. I am current and qualified in the Gulfstream 5/550.


    Rick

    Hello Rick,


    Welcome to the AF2 forum. We can always use more real world pilots to assist in the tweaking.


    I am an old retired corporate jet pilot myself - mostly small Citations and older Lears. I worked for Grumman way back when they were building the Lunar Module. They flew our paycheck from Bethpage to Titusville, FL every Friday on their Gulfstream I. Seems like a million years ago. :(


    Regards,

    Ray

    A steely-eyed Sierra Hotel record setting F-15E Strike Eagle simulator pilot. 8o
    Out now: Hawaiian Islands 8) Part 1: Kauai + Niihau v2 and Part 2 Oahu Island.

    On short final Part 3: Molokai, Maui, Lanai, Kohoolawe + Molokini Crater



  • Its nice seeing some of the Grumman / Gulfstream family around here. Some of you may have noticed my title (GACSavannah)... GAC honors the job (Gulfstream) and Savannah is where I am based, with this being the home of product manufacture for GII,III,IV,V, 300,400,350, and 450 in the past and currently the point of origin for the G550, G650, and the new G500, G600, along with the largest Product Support facility in our system (Largest dedicated Corporate Aviation maintenance facility in the world in fact).

  • Its nice seeing some of the Grumman / Gulfstream family around here. Some of you may have noticed my title (GACSavannah)... GAC honors the job (Gulfstream) and Savannah is where I am based, with this being the home of product manufacture for GII,III,IV,V, 300,400,350, and 450 in the past and currently the point of origin for the G550, G650, and the new G500, G600, along with the largest Product Support facility in our system (Largest dedicated Corporate Aviation maintenance facility in the world in fact).

    . . . . and GACSavannah is the most talented flight sim repainter in this neck of the woods. Just check out all those super slick Learjet 45 repaints in the download area. :):P8)


    Regards,

    Ray

    A steely-eyed Sierra Hotel record setting F-15E Strike Eagle simulator pilot. 8o
    Out now: Hawaiian Islands 8) Part 1: Kauai + Niihau v2 and Part 2 Oahu Island.

    On short final Part 3: Molokai, Maui, Lanai, Kohoolawe + Molokini Crater



  • Thank you Ray, very nice of you. I just wish they would give us a set of templates for the Q400. I see all kinds of great potential for that one.


    I gotta say that I was really surprised and very humbled to see Orbx use two of those repaints in the preview shots when announcing Monterey and Eagle for AeroFly. I have been a customer of theirs for years with the FS/P3D line of products, so that was really neat!

  • Thank you Ray, very nice of you. I just wish they would give us a set of templates for the Q400. I see all kinds of great potential for that one.


    I gotta say that I was really surprised and very humbled to see Orbx use two of those repaints in the preview shots when announcing Monterey and Eagle for AeroFly. I have been a customer of theirs for years with the FS/P3D line of products, so that was really neat!

    All very well deserved comments.


    I would have thought we would have the Q400 repaint templates by now, but evidently the only person that produces these templates has higher priorities. Yes, those Learjet 45 repaints of yours do indeed stand out in the Orbx sceneries.


    Maybe one day you can do your magic with a couple of military repaints for the Lear. If so, I’m hoping for a Navy edition. Maybe black ops or something. 8)


    Regards,

    Ray

    A steely-eyed Sierra Hotel record setting F-15E Strike Eagle simulator pilot. 8o
    Out now: Hawaiian Islands 8) Part 1: Kauai + Niihau v2 and Part 2 Oahu Island.

    On short final Part 3: Molokai, Maui, Lanai, Kohoolawe + Molokini Crater



  • > Maybe one day you can do your magic with a couple of military repaints for the Lear. If so, I’m hoping for a Navy edition.


    I did do a navy training version, the white with red. I don't recall if I ever uploaded it though? Or perhaps there may have been an issue with the upload? I don't know.


    When I get home tonight I will take a look, and if it's not available here, I can zip it up and upload it.

  • Nice to see other jet pilots messing round here . Currently my job is to fly my super rich boss around in his new Challenger 300. This gives me ample sim time in my hotel in real trips. Can’t get enough of AF2 now especially with Sound plant 45 utility ( google it ) for add on sound effects galore as well as JOYTOKEY utility ( google it too ) for attaching sounds to any button!!! Brings in the immersion we were missing by poor overall sounds in this sim.


    Now I have X-plane and FSX on hold as I love the feeling and vis aspects of this sim!


    Peter

  • Nice to see other jet pilots messing round here . Currently my job is to fly my super rich boss around in his new Challenger 300. This gives me ample sim time in my hotel in real trips. Can’t get enough of AF2 now especially with Sound plant 45 utility ( google it ) for add on sound effects galore as well as JOYTOKEY utility ( google it too ) for attaching sounds to any button!!! Brings in the immersion we were missing by poor overall sounds in this sim.


    Now I have X-plane and FSX on hold as I love the feeling and vis aspects of this sim!


    Peter

    Peter,

    Are you using the freeware version of Soundplant 45? Can you post a link for the actual sound files?


    Regards,

    Ray

    A steely-eyed Sierra Hotel record setting F-15E Strike Eagle simulator pilot. 8o
    Out now: Hawaiian Islands 8) Part 1: Kauai + Niihau v2 and Part 2 Oahu Island.

    On short final Part 3: Molokai, Maui, Lanai, Kohoolawe + Molokini Crater