Alpha Floor Posted June 6, 2020 Report Posted June 6, 2020 Gentlemen, Another issue caught today while live streaming. This time it caused me a rejected take-off. TOWS kept going off. The usual suspects are: - Flaps set for take-off - Stab trim in green band - Speedbrakes fully down - Parking brake released But it still kept going off. Anything I am missing here? https://youtu.be/MNCTzcAPfQI?t=14503 Jump to 4:01:43 I had a normal take-off earlier at 1:05:00 with no alarms, for the record. Quote
Litjan Posted June 7, 2020 Report Posted June 7, 2020 There have been reports of this happening on subsequent takeoffs...I have not been able to narrow this down, but it could be related to speedbrake position. I think that maybe the "speedbrake extended" position is retained in memory and not getting reset. Maybe related to the replay code. I will do some more testing. When it happens, try to pull the speedbrake up and then push it back down all the way. Thanks for the report, and compliments on the professional way you handled the aborted takeoff! Cheers, Jan Quote
Litjan Posted June 7, 2020 Report Posted June 7, 2020 I think I may be on to something... If you want to make sure this doesn´t happen for now, reboot gizmo during your stop at the gate (pick "turnaround" as a spawn option). Cheers, Jan Quote
Litjan Posted June 7, 2020 Report Posted June 7, 2020 Also - make sure that your speedbrake lever is really all the way down. When using the mouse or a hardware lever it is really easy to not push it forward completely. Looking at your video closely it looks like it MIGHT not be in the full forward position. In the real airplane we had that problem as well, from time to time. The first thing the CPT would do when the takeoff warning went off is to slap the speedbrake handle a bit. Sometimes the position switches got worn and would need a little whack. Note that you do not arm the speedbrake for takeoff like you would in an Airbus. I will nevertheless look over the code with Tom, and I will also "relax" the requirement for the speedbrake position a bit. Right now it must be 0 for the alarm to not sound, so any "spiky" axis assigned to speedbrake or a manual retraction to 0.000000001 would still trigger the alarm. Cheers, Jan Quote
Alpha Floor Posted June 7, 2020 Author Report Posted June 7, 2020 6 hours ago, Litjan said: There have been reports of this happening on subsequent takeoffs...I have not been able to narrow this down, but it could be related to speedbrake position. I think that maybe the "speedbrake extended" position is retained in memory and not getting reset. Maybe related to the replay code. I will do some more testing. When it happens, try to pull the speedbrake up and then push it back down all the way. Thanks for the report, and compliments on the professional way you handled the aborted takeoff! Cheers, Jan Hey Jan, thanks for your quick comment! I think it must be something with the Gizmo plugin, I will reboot it between flights as you said! For information: I have the speedbrake assigned to a rotating knob in my Saitek X-52 Pro. The knob was rotated all the way up but as you said, some noise in the signal may be sending a slight non-zero value... And kind thanks for the compliment. If unsure, better to reject the take-off at a low speed than continue with the uncertainty of what is going on... only to find out on rotation... Quote
Litjan Posted June 7, 2020 Report Posted June 7, 2020 Yep - and us disabling the TOWS is also not a good option: https://en.wikipedia.org/wiki/Spanair_Flight_5022 But I will check the code again with Tom and put in a little bit of "leeway" for the lever to be at zero. A lot of the controls on a joystick axis will not "jump" to the setting of that control unless it is moved in X-Plane. So it could be that - if you never thouch that knob - the position of the lever remained at "0" for the first takeoff. Only after using this lever during flght, the speedbrake maybe retracted to 0.0001... You can also doublecheck in the "DATA OUT" setting for flight controls in X-Plane to see if your axis is really commanding 0, or only close to it. Cheers, Jan Quote
Litjan Posted June 7, 2020 Report Posted June 7, 2020 Oh, one more thing - when you do a video like that, you can always "push forward really quick" one of your thrust levers while taxiing out to the runway (with everything set for departure). Just a quick jab won´t really accelerate the engines, but the horn would sound right away. Cheers, Jan Quote
JetNoise Posted June 7, 2020 Report Posted June 7, 2020 (edited) Hi Jan, and if posible, add another "leeway" for the Speedbrake lever at its "armed" position, since this is (not always) blocking the Speedbrakes to deploy fully on touchdown. I am using a 6 Lever THR-Quad (Boeing type) TQ6 atm. Of course, any other kind of solution is very welcome ;-) Grüße Oliver Edited June 7, 2020 by JetNoise 1 Quote
Alpha Floor Posted June 7, 2020 Author Report Posted June 7, 2020 (edited) 53 minutes ago, Litjan said: Oh, one more thing - when you do a video like that, you can always "push forward really quick" one of your thrust levers while taxiing out to the runway (with everything set for departure). Just a quick jab won´t really accelerate the engines, but the horn would sound right away. Cheers, Jan Ah yes! I tried it out when taxiing back to the holding point, and indeed, it kept going off. I just decided to ignore the horn the second time and carry on. If this happened in real life, Jan, a TOWS horn that goes off for no apparent reason. After aborting a take-off and troubleshooting, what would you do? I guess you'd contact your companies maintenance and let them know? Maybe they would ask you to pull and push the corresponding CB to reset the system? Eventually you would just take-off and ignore the horn or would the flight be cancelled? This was out of base on a return flight. I guess the decision to cancel the flight is also dependent on whether you're in or out of the company base. Edited June 7, 2020 by Alpha Floor Quote
Cptburgos Posted June 7, 2020 Report Posted June 7, 2020 8 minutes ago, Alpha Floor said: Ah yes! I tried it out when taxiing back to the holding point, and indeed, it kept going off. I just decided to ignore the horn the second time and carry on. If this happened in real life, Jan, a TOWS horn that goes off for no apparent reason. After aborting a take-off and troubleshooting, what would you do? I guess you'd contact your companies maintenance and let them know? Maybe they would ask you to pull and push the corresponding CB to reset the system? Eventually you would just take-off and ignore the horn or would the flight be cancelled? This was out of base on a return flight. I guess the decision to cancel the flight is also dependent on whether you're in or out of the company base. As real life engineer working on this plane, i can tell you that if a troubleshooting per manual didn't find the issue, we shoot directly to MEL, i'm pretty sure it is a NO GO item so, flight canceled 2 Quote
Dozo Posted July 3, 2020 Report Posted July 3, 2020 On 6/7/2020 at 10:04 AM, Litjan said: Also - make sure that your speedbrake lever is really all the way down. When using the mouse or a hardware lever it is really easy to not push it forward completely. Looking at your video closely it looks like it MIGHT not be in the full forward position. I also had alerts when taking off and couldn't really figure out what I was doing wrong. Turns out that this suggestion was spot on. I had an axis assigned to the speedbrakes. I replaced it with two pushbuttons (extend one, retract one) and that worked out for me. A bit more leeway would be nice indeed :-) Quote
Litjan Posted July 3, 2020 Report Posted July 3, 2020 52 minutes ago, Dozo said: A bit more leeway would be nice indeed That is already included for next patch! Cheers, Jan 1 Quote
joni80 Posted July 8, 2020 Report Posted July 8, 2020 So the thing that I found with this "bug" was that once retracting the speedbrake via my rotary knob, the speedbrakes retracted. Yet when I clicked on the speedbrake, to move it with my mouse, it immediately jumped to the fully extended position, and only upon retracting it with my mouse/axis a second time the TOWS would not engage for this. So from my experience it wasn't that the rotary knob didn't retract the speedbrake fully, but rather that some code still thought the speedbrakes were fully extended. Quote
Litjan Posted July 8, 2020 Report Posted July 8, 2020 Interesting...there may be something amiss here. When I watch a landing in replay my speedbrakes always pop to "full up" when I end the replay...no matter what I did during the flight (I make sure I really really retract them before starting the replay)...Tom has added some code to make the spoilers move smoothly during replay, I wonder if this could interfere with the operation. To be safe - I would always recommend rebooting gizmo between consecutive flights - even though our goal is, of course, to allow consecutive flights. Cheers, Jan Quote
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