A320 oddities

1st Official Post

    Now upon landing when I engage reverse thrust it stops the A320 in about five seconds. Anyone else seeing that?

    Also, the autopilot doesn't want to engage until about 30 seconds to a minute after takeoff instead of the few seconds after takeoff that it used to be able to engage.

    And the autothrottle on approach and landing seems screwy. The display will tell me to apply drag, and when I do and the speed comes down the engines rev up and increase the speed again.

    This is addition to the sudden banking that occurs when the autopilot is disengaged, which I know has been reported.

    Recently I have been flying the Q400 for the most part, so if these are all known problems with the A320 I apologize.

    • Official Post

    You have to hold down the reverse key for continuous reverse.

    There is no time delay implemented as such, it could be that the angle of attack is too high yet, known issue. Please be patient for that update :)

    Related to that angle of attack issue (stall protection kicks in too early) the thrust will be increased to TOGA when flying too slow. The drag message has nothing to do with the autothrust system per see.

    Edit: Do you have the flaps extended? Because if you leave them in the aircraft won't slow down below the -S speed during the approach. To decelerate extend flaps and slats when the speed permits. Then the autothrust system will slow down to approach speed eventually.

    The banking on disconnect is also already fixed in my developer version. I've tested it before the release but it slipped through. I didn't fly on autopilot long enough, just checked if it still works and if the fully automatic landing was still available. Sorry for that.

    • Official Post
    Quote from 105OE

    If you reduce your speed your are actually decreasing drag. The A320 doesn't want to you to slow down when this message appears.

    This means that you are to high (slow) to maintain the required descent path.

    You can increase the speed to increase drag, and/or extend the speedbrakes.

    The drag message isn't 100% accurate yet. I plan to redo it soon and add the intercept arrow as well. I'll also work on the top of climb and end of descent point calculation and try to remove any unwanted "decelerate" messages during the approach.

    There doesn't seem to be any question that it wants me to slow down when I get the "increase drag" message because I am in fact over the desired speed set by the autopilot. This is usually because the descent mode has placed me in a very high rate of descent. I deploy some spoiler because the engines are already in idle.

    I look forward to the next update. Thanks for all the hard work!

    • Official Post
    Quote from Oldar

    There doesn't seem to be any question that it wants me to slow down when I get the "increase drag" message because I am in fact over the desired speed set by the autopilot.

    Again, the increase drag message doesn't just come from high speed. If you just fly too fast the message is NOT created. Flying fast is only part of the equation. You also have to be high on profile, above the panned descent profile and too high and too fast to be able to be low enough for the next altitude constraint.

    1/4 airbrakes should be enough to recover from being to high and too fast but if the auto thrust system starts to advance the thrust you should store the speed brakes.

    Ok, got it.

    But If I am too high/too fast it is because the autopilot hasn't set the descent rate/autothrottle combination correctly. All I have done is select the proper final approach altitude and pressed the altitude button. The autopilot then decides what my descent rate and throttle setting should be, correct? I haven't made any other inputs.

    • Official Post
    Quote from Oldar

    Ok, got it.

    But If I am too high/too fast it is because the autopilot hasn't set the descent rate/autothrottle combination correctly. All I have done is select the proper final approach altitude and pressed the altitude button. The autopilot then decides what my descent rate and throttle setting should be, correct? I haven't made any other inputs.

    Well if you push the button too late, way later than the top of descent (DECELERATE shown on the PFD), then the autopilot has no chance to get rid of the excess energy and shows (INCREASE DRAG) during the descent, because it only varies the managed speed by about 20kts up and down, that is not enough to descent that much faster. It asks you to extend the speedbrakes because it can't extend them automatically. But that should all happen in the descent, not in the approach. And if it asks for increased drag, just extend the speedbrakes for a bit until you are back on profile, visible as green dot on the altitude tape and also on the speed tape, when the current airspeed is within the magenta markers for max and min managed speed flown with idle

    When descent further and pass the "D" point on the map (deceleration point) the autopilot will pitch up to slow down from 250kts to -S speed (flaps up), -F with CONF 1 to 3 and vapp with full flaps. After pressing the approach button the glide slope will be intercepted and then you should be fully configured before 1000ft... and then the automatic landing does everything for you but you have arm the approach, then manually set flaps, extend the gear and also monitor the aircraft speed to see if the speed is maintained at -S or -F, then extend flaps further... arm the ground spoilers, set auto brake,....

    I'm going to write a tutorial on the A320 but I'm not finished with the Learjet tutorial yet, I'm working as fast as I can :)

    In the mean time there are plenty of A320 videos on the autoflight system on the internet. You can use the real world training videos on YouTube and perform the same actions in the Aerofly A320 (except the interaction with the MCDU at the moment).

    Thanks for all the answers.

    The only issue with the TOD point is that it often wants me to start descending at 260 or more nautical miles from the target, and then if I let it the autopilot will drop me down to 2000 agl 140 miles out! So as PIC I disregard that and usually start my descent between 120 and 140 miles out depending on my cruise altitude.

    • Official Post

    I've never had that issue before and I would like to hear more information on how to reproduce that issue. Can you send me your route (type the waypoints as shown in the navigation menu at the bottom)?

    Are you sure you are looking at the right TOD symbol on the map? What is your green dot on the altimeter indicating? Is it parked at the top or bottom or does it start moving down at those 260 miles out?

    How can "1050E" say that his A.320 works correctly in automatic land, and "Oldar" has the same difficulties that I have with that airplane in automatic landing?.

    Oldar, and all the others that have problems similar to this one, my advice is not to insist with these operations, since that airplane, seems not to be sufficiently finished, consequently, in certain circumstances, it does strange maneuvers. We must wait for the necessary improvements to fly properly.

    Be that as it may, it is obvious that this plane, needs to improve certain characteristics that I do not know, but it is clear that it is definitely not finished. Consequently, flying under certain conditions results in a fight against an unfinished product.


    I will not fly again with this A.320 until it is finished and also finished its "flight manual".


    Regards: Delfin

    Well, we have an autopilot that is good for folks who have A320 certificates in real life, but maybe not ideal for the rest of us! (Sorry, I couldn't resist)

    I would be delighted if you could just roll back the autopilot to where it was when it was released along with the Q400. It was much more dependable and comprehensible to me then.

    • Official Post

    Oldar and delfinpm, can you please check if you are on the beta version of the Aerofly FS 2? I'm guessing 105OE already is and he seems to have fewer issues.

    BTW, the too high too fast issue was also present in the earlier autopilot if you descended to late. And I actually haven't made any changes to the autopilot since last version... I've changed the fly by wire of the A320...

    However, I'm still working on the Fly By Wire of this aircraft and I urge you to try the latest FBW version once it is released to make sure the issues that you currently have are gone. I've tested the Steam beta version and it seemed good enough for me, yes the stall protection did kick in a bit too early but I still managed to to an approach and fully automatic landing, it wasn't that bad. After lift of at 50ft, autopilot on, climb to cruise altitude, select lower altitude, wait for TOD, press the button, wait a long time and when I got near the runway, arm approach, before green dot speed was reached flaps 1, then well before -F speed flaps 2, and as soon as possible flaps 3 and full, it worked perfectly without any issue, like before. Then fully automatic landing, also worked like a charm. So overall I judged: autopilot still works, we can release that intermediate state of the fly by wire.