Airbus 320... WOW!!!

  • To disconnect the autopilot of the A320 use the assignable button commands for the autopilot disconnect. I think I had a version where you can click the sidestick as well, don't know if that is implemented in the public beta though.

    Good news! I just did another autoland and I was able to disable the AP using the red button on the sidestick! So this has been implemented in the update and works as it should already! Nice! So no need to work on the AP buttons themselves! :)

    The reverse has to be assigned in the controls as well. I have the xyzwhateverforgotthename throttle quadrant with three buttons that are triggered when I move down the levers. I use them for reverse, works really nice.

    I assigned a button to the reverser on my joystick and it works like a charm. I do have to keep the button depressed for as long as I want to use the reversers (the button doesn't work as a toggle) but that's fine with me.

    One odd thing: I have a Logitech Extreme 3D Pro joystick which has a rudder twist. I don't have it assigned to anything though because I have rudder pedals. However, when I am standing still on the ground I noticed that when I move that twist, the PEDAL DISC 'thing' to the left of the sidestick turns along with my movement of the twist...?! That thing can't be clicked or anything but it does move when I use that twist. I looked all through my controls but the rudder twist wasn't assigned to anything. Whenever I use this twist I also see the rudder indicator at the top of the PFD move left and right! When I start to move the plane the PEDAL DISC keeps on moving until speed reaches 40 kts: until then the rudder indicator also moves along with it, but the plane doesn't move accordingly (it does when I use my rudder pedals). At speeds above 40 the PEDAL DISC is stuck when I move the twist.

    Nothing serious or problematic but I am wondering what this is. ;)

    • Official Post

    The PEDAL DISC is just a button on the tiller. The tiller is used to control the nosewheel steering. You can assign a different axis in the controls just for the steering. If you don't assign an axis your rudder will be used to generate a tiller signal. So in your case the twist handle is either still assigned to the steering tiller or your twisting is used to generate the steering. As speed increases the deflection of the nose gear is reduced from almost 90° to only a few degrees since you don't want the nose gear to slide across the ground.

    Now the steering of the nosegear can also be done by the rudder pedals in the real world. The maximum deflection of the nose gear with just pedals is only 6 degrees which is enough for keeping the aircraft on the centerline but not enough for tight turns. This is where the tiller is used in real life.

    If you depress the PEDAL DISC button on the tiller (not modeled yet) you can remove the steering by pedals. Then you can fully deflect the rudder pedals for a control check while moving and the aircraft will no longer steer left and right. When you release the button the system returns to normal operation mode.

    So to summarize: You can assign your twist handle to the tiller function in the Aerofly FS 2, the spring loaded PEDAL DISC button is not implemented yet. Well I have it implemented but it's disabled since you can't to a "activate while mouse button is down" type of thing yet. And since the 3D model of the tiller doesn't allow the pushbutton to be depressed there is no way of telling if it's on or off. So i removed it for now.

    • Official Post

    1. The pedals are locked in the center position and if you overcome the breakout force and somehow manage to only deflect the pedals it's not that bad. Plus if you stopped it's not really a factor.

    2. Yes with tiller input the AP might not disconnect and your steering tiller might not work while the AP is on. I can implement that the tiller is useless as well.

    I would like to add the simulation of the breakout forces of the stick and pedals as well... This needs to be optional though, don't know how a setting like this can be done yet. I'll look into it. If you have an iPad and turn on the autopilot the last thing you want is a nose dive when you put the tablet down on the table.

  • The PEDAL DISC is just a button on the tiller. The tiller is used to control the nosewheel steering. You can assign a different axis in the controls just for the steering. If you don't assign an axis your rudder will be used to generate a tiller signal. So in your case the twist handle is either still assigned to the steering tiller or your twisting is used to generate the steering. As speed increases the deflection of the nose gear is reduced from almost 90° to only a few degrees since you don't want the nose gear to slide across the ground.


    Now the steering of the nosegear can also be done by the rudder pedals in the real world. The maximum deflection of the nose gear with just pedals is only 6 degrees which is enough for keeping the aircraft on the centerline but not enough for tight turns. This is where the tiller is used in real life.

    Cool! To tell you the truth I never used the tiller up to now... =O But I just assigned that twist axis to it and WOW that's cool indeed! I always had to use the rudder AND toe brakes to make tight turns... stupid me. :huh: Not anymore! The tiller works like a charm and it is nice to have some use of that twist option of my joystick. ;)

    In the meantime I also assigned button 2 to disengage the AP: it is a little button on the sick itself, just like the red one in the Airbus. Clicking on it in the VC does work but just like using the joystick for throttle and reversers (and aileron and elevator) it kind of feels okay and natural to use that little button on the joystick for this anyway.

    LOL The new Airbus made me redo a lot of controller settings! I am soooo happy with the Airbus right now! And then to think this is only one plane and that I've still got the Dash to check out! (I am not a fan of fighter planes and Boeing, I am sorry to say, so I don't plan to master all planes but the Dash I will certainly check out! ;) )

  • It actually is Jeroen and not Jereon but it is still recognizable enough so no problem, JetJeckoy10/Rya. 8o

    Hello Jeroen,

    I never could spell those foreign names correctly. Sorry, but thanks for the correction. ( I actually checked over at Avsim, and that is the spelling used most often for you. duh.) Now I have a way of remembering - Jero rhytmes with Hero.

    Regards,

    Rya, err Ray

  • Hello Jeroen,

    I never could spell those foreign names correctly. Sorry, but thanks for the correction. ( I actually checked over at Avsim, and that is the spelling used most often for you. duh.) Now I have a way of remembering - Jero rhytmes with Hero.

    Regards,

    Rya, err Ray

    ^^

  • Funny little 'bug' or oddity in the Airbus: when the PFD showed MORE DRAG I could see the top of the letters DRAG on the videoscreen next to the door. Seriously! I checked it a few times (turning the speedbrake on and off) and DRAG showed up everytime on that videoscreen! LOL No problem at all, of course, but quite odd. ;)

    • Official Post

    Funny little 'bug' or oddity in the Airbus: when the PFD showed MORE DRAG I could see the top of the letters DRAG on the videoscreen next to the door. Seriously! I checked it a few times (turning the speedbrake on and off) and DRAG showed up everytime on that videoscreen! LOL No problem at all, of course, but quite odd. ;)

    Uh that is interesting! Nicely spotted!

  • I am so pleased and impressed with the autopilot on the 320. I can't say it enough, so I will say it one more time: just a superb job. Thanks for providing me with what will be many many hours of pleasant diversion from the real world.

    • Official Post

    With the TOD indicated on the screen it's not likely that you are going to miss it and you know that you should descend.

    It's much more likely that ATC doesn't let you descent when you want/need to (about 90 times out of 100)

    For that reason the Airbus wants you to decelerate as you are already too high/fast as you are apparently not able to descend for whatever reason.

    That makes sense, yes. If ATC doesn't clear you down at least start to reduce the energy of the aircraft by reducing speed.

    Thanks!

  • To the Autopilot masters during "LAND" mode question:

    According to my real world A320 contacts the FCU is not completely locked, autopilot master and autothrust pushbuttons are available during the LAND mode. You should also be able to disconnect the autopilot via sidestick and pedals during LAND mode but no one tried that yet. :D No info about the tiller yet, I guess it would just not work.

    But the LAND mode cannot be disengaged by pressing or pulling any other mode button. That just means you can't change to mode to HDG/TRK or OP CLB, V/S or FPA when you are below 400ft with the ILS approach locked in.

    I now changed it in my autopilot code and these changes should be pushed out in the next updates.

  • I also played around with the Fly-By-Wire of the A320. After a bit of research I think I now got the protections and C* law right or at least close to the real deal. Didn't know that you could fly at a constant VMO+15kts when you hold the stick forward... Also found out that the maximum pitch angle is reduced from 30 to 25 degrees when below VLS... and I think I got the bank protection and auto-return to 33° right now, at least it looks identical to the real world videos. Had to watch a couple videos to get there but now it is pretty good and very intuitive, better than anything I have tried what is on the market right now. E.g. if you hold half deflection to the side the aircraft rolls to about 45° and then stops. Then increase to full deflection and the aircraft rolls to 67°. Reduce to half deflection and it rolls back to 45° smothly. Let go and it returns to 33°. That means above 33° of bank the stick deflection linearly increases the bank angle, below that it just controls roll rate.

    And above 33° the pitch up support doesn't just stop, it is maintained from what I have seen. So if you try to do a turn at 35° you pretty much get away without pulling at the sidestick, you would only need to pull for the extra 2°. This is very nice when you want to increase the bank but don't pull further, g-load is the same but turn radius decreases but you trade it for increasing sinkrate... In other products on the market the support is suddenly taken away which feels very odd and the video's I've seen don't confirm this either.

    Also added C* law, made sure the fly by wire transitions correctly between direct modes and fly by wire ones. E.g. on ground you now have direct roll which transitions over to the normal roll mode over a period of one second, then you have the pitch direct mode, flight mode and flare mode, transitions are between 1 and 5 seconds.

    Overall I think I got a lot of things correct now, have to do a bit more research on the flare law, still doubt that it lowers the nose into the ground in the flare, I think it just reduces the delta pitch that you pull up after flare engaged... (maintains flare attitude and reduces pitch to get back there). And on the ground sure, lower the nose, why not, that is safe.

    Another question would be load alleviation, I read the NEOs (and possibly CEOs) variants of the A320 have it and very early models had it as well. I may skip that for now :)

    To sum it up: we're not done yet :)

  • I'd be happy if the correct flightpath stability would be implemented (attitude increase with decreasing speed) and not only attitude hold.

    50ft is the reference attitude and at 30ft a single nose down input is generated to achieve a -2° pitch attitude within in 8sec.

    In fact IRL I never noticed it, although 'theoretically' it introduces a noticeable nose down pitch moment to make the pilot actually flare the A320.

    It's so natural that even when closely monitoring it I couldn't tell if it was doing anything.

    The flight path is more stable at the moment and yes pitch increases or decreases with speed to try and maintain the C* = 1/g * ( -nz + vm * pitch_rate ). But it is only a short term stability and I might add in compensating terms, e.g. to directly counter flap effects or thrust changes. I believe the real world aircraft has those, otherwise the flaps are just another gust which are not compensated long term. Would be better if the flight path remained constant in configuration changes, C* alone doesn't do that as far as I know. Also the asymmetric thrust compensation.... that is going to take a bit of time. I already added in a term to fight the roll rate induced by the conventional rudders. Should make cross wind landings a lot easier if the wing doesn't drop.

    To the flare law: I think it is the same C* law, just with another very slight nose down tendency. Are you sure it reduces it to -2° in 8s or by -2° in 8s?

    I think you can't notice it IRL because the ground effect works against that. And it only makes much of a difference after touch down. Currently I can release the side stick and the nose stays up, that is what the flare law should prevent I think. That means I have to do something about it so why not do it correctly as well? :)

    Then there are all the transitions between flight to flare, flare to ground and ground to flight mode... LOL

    They are already working, yes. I got direct roll or normal roll, direct pitch, normal pitch, flare so far.

    With a bit of extra code I might be able to put in functions to revert to direct law in flight. In case you select couple computers to off for example...

  • BTW. you can now cancel the A.FLOOR function by pulling the thrust levers to idle or per autothrottle disconnect (haven't tried the latter yet). I've seen that in videos as well, though this was impossible. Another example where different add ons for other simulators differ in accuracy. Even the better ones have inaccuracies in them.

  • 1. I won't overdo it then

    2. I'm leaving a bit rolling effect, natural roll compensation should counter the rudder input, there may also be a compensation from the yawdamper, so yeah, I'm doing something, not everything

    3. OK, I played around with it, currently I let the reference pitch decrease below 30ft RA. It linearly drives to -2.0 deg over a period of 8 seconds. The actual nose down of the aircraft I use is linear to the difference of this pitch reference and the current pitch. The more you pull up the nose the stronger the down force. I can fine tune this later, need pilot input for this. This means if you are not pulling up the nose dive is barely noticable. But if you start to pull up the nose you feel the aircraft wanting to take the nose down. Feels quite good. Over the period of 8s this nose down tendency increases as well, so sounds good to me. I don't think the decrease of pitch attitude just flicks to on at 30 ft RA, does it? Right now it is not really noticeable which is really nice.

    4. When the ground mode activates the nose is already low, I need to reduce up to 12 deg of pitch before that happens... (tailstrike? :D )

  • ok after being a boeing driver for 20 years i am giving the airbus a320 a go as it is got a good FMC at this point with Aerofly FS2, I am getting confused with my landing as on the landing page it is telling me the approach speed is at 108 kts i know this seems very low and when doing the flight the plane is automatically kicking in the throttle to not stall the plane around 160 kts (seems more reasonable) i have tried dialing in the speed to around 160 kts as pilot intervention and clicked on the a/thr button but this does not seem to do anything,

    so can someone please help me with the correct process of maintain appropriate airspeed on the final approach in the A320 as leaving into the the autopilot makes the ac stall and me intervening does not seem to do anything,

    amazing plane by the way it is so many less procedures than the boeing 737 or 747.

  • I've never gotten the approach speed to show 108 kts, so what exactly did you do to get there? :D

    Correct speed for approach is 135 to 140 kts for flaps 3 or FULL. 160 is way too high... Vref in the airbus is indicated by the first yellow line, as long as you're above that VLS - velocity low speed (not lowest selectable, which a lot of people say)... as long as you are above that thin yellow line you're good. Protections only kick in much later, at even slower speeds.

    When you click the a/thr button it just arms the system, the button should then turn green (so it does something...). Move your throttle levers to the "CLB" detent to activate autothrust. It even flashes "LVR CLB" (lever climb) on the primary flight display, which is very hard to miss.

    Have you seen our wiki page for the a320? https://www.aerofly.com/dokuwiki/doku.…aft:airbus_a320