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Tom Knudsen

[Solved] Something wrong?

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LOL.. Well according to the images there is, just thought the images was funny however the core issue isnt.

Anyway, this is just after takeoff ENGM when I just engaged the VNAV, plane immidiate banked left, and rolled.

Guess it did not like the VNAV

2017-02-24_195151.png

Not sure if it was an contributed factor, but notices the right Flight Director was off

2017-02-24_195449.png

 

Any idea what might have triggered it?

Included the debug file, not sure if any else is needed?

 

IXEG_FMS_debug.txt

 

Edited by Morten

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I guess the biggest problem in this case was that you did not engage the autopilot. You can still clearly see FD in green on your EADI - it would be CMD if the autopilot was flying...

Jan

 

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Hm, not sure - on the first pic, the AP is clearly not engaged (visible on the EADI, but also the CMD A button is not lit). In the second pic, we don't see the EADI, but the CMD A button is lit in green. Looks more the AP was engaged with the FD already following LNAV and VNAV.

From the log I would guess the problem is your route didn't permit for FL310 - apparently VNAV calculated the TOC to be at 9,983 ft, before reaching ADEXA (cf. VNAV calculations in your log file). Apparently you were climbing beyond the calculated TOC manually and then engaging the AP with VNAV and LNAV engaged. I suppose this could be linked to some ALT and/or Speed constraints in the selected STAR.

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6 hours ago, Litjan said:

I guess the biggest problem in this case was that you did not engage the autopilot. You can still clearly see FD in green on your EADI - it would be CMD if the autopilot was flying...

Jan

 

Autopilot was disengage just before the image was taking, In the process of correcting the bank angle to gain control. Manged to reengage the autopilot when plane was stable.

Though I never know why the plane turned back with the autopilot egange. the CRS Lock was green in the EADI along with some other CRS labels. Sorry do not have any image of this.

I landed fully at ENVA except the plane never capture the VOR lock at the arriving airport, so I needed to again override to land manually.

AIRAC is the latest version by NAVDATAPRO

Edited by Tom Knudsen

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Ok, so I did a new flight today, second try sort of speak..

And I want to care about this aircraft, but it makes it hard to love it. Shit don't work and I don't know what to do or how to fix it.

Flight went good at least up to the approach. Out of the blue it started to roll left for a 360 roll like it was a #¤"%# fighter jet. This totally ruined my flight and

it was no way to fix it or even reengage the autopilot.

 

Luckily this time I captured videos of the darn thing.

As of now this aircraft is totally useless and not reliable at all :( (version 1.07 hotfix)

 

There is no way to upload the video here, but I will link it for you to see (3 in total)

Film 1

http://www.tknudsen.com/movies/1.wmv

Film 2

http://www.tknudsen.com/movies/2.wmv

Film 3

http://www.tknudsen.com/movies/3.wmv

 

I would upload the debug text, but X-Pilot will not let me do so

http://www.tknudsen.com/movies/12.png

 

 

 

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as per your vid, anytime you engage the AUTOPILOT the aircraft immediately enters CWSP & CWSR mode. This means the aircraft is receiving pitch and roll input from the yoke overriding A/P.

Most likely you use a desktop grade yoke/joystick and the potentiometers are sending spike signals continuously (quite common on desktop grade hardware and coming worst with aging), the aircraft "thinks" you want to regain control (as it happens on the real thing if the pilot manipulate the yoke having a/p engaged) and goes CWSP & CWSR modes to concede control.

 

Please try going to the 737 left side menu, preferences and move the CWS nullzone slider all the way to the right. This will increase the simulation capacity to ignore input from the hardware while A/P is engaged.

 

hope this helps.

 

check also your hardware is fully calibrated.

 

Edited by mmerelles
misspelling

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Thanks, that helped. Narrowed it down to this - A faulty connection on my Saitek Flight Yoke Throttle

It was connected to the flight yoke via an PS2 connection, so basically what happend (i think) was that it disconnected mid flight

From log.txt

1:22:09.953 D/HID: Hardware REMOVED Saitek Pro Flight Yoke
1:22:09.953 I/JOY: UNREGISTER Joystick device: Saitek Pro Flight Yoke - VID:1699PID:2988
1:22:12.245 D/HID: Hardware ADDED(06a3, 0bac) - Saitek Pro Flight Yoke at path \\?\hid#vid_06a3&pid_0bac#9&2b316ab&0&0000#{4d1e55b2-f16f-11cf-88cb-001111000030}

 

So basically I believe this happened, not sure but It must be. The only logical explanation!!

I ordered a new flight controller system, did not bother to buy a new USB flight throttle system to replace the ps2

So if anyone want a fully working Saitek Flight Yoke, let me know (the throttle which PS2 connector is fault, I do believe should be replaced.

 

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PS How come I cannot enter WIND CORRECTION for the approach.

This time around the wind component was 31 knots. But when entering this I get an invalid entery error message2017-02-25_141732.png

 

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PS How come I cannot enter WIND CORRECTION for the approach.

This time around the wind component was 31 knots. But when entering this I get an invalid entery error message2017-02-25_141732.png

 

Because 15kts is maximum for Wind correcting the Vref. Google it and See what that correction really does. Its not the Wind components that wie put in there ;) it is 1/2 of the HEADWIND plus difference between steady and gust winds (gust factor) min 5 max 15 ;)

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Ok so rwy metar 18031G40 would be

Sent from my SM-G928F using Tapatalk

As I see your ILS course is 255. so headwind is about 12kts (180-255=75, 0.9-.75=0.15, 0,15+0.2=0.35, 0.35x31=12). 1/2x12+9=15 . so the value you have to put in should be 15.

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1 hour ago, rcfreak07 said:

As I see your ILS course is 255. so headwind is about 12kts (180-255=75, 0.9-.75=0.15, 0,15+0.2=0.35, 0.35x31=12). 1/2x12+9=15 . so the value you have to put in should be 15.

Damn, thanks a bunch. So I learn a lot right there :)

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16 hours ago, rcfreak07 said:

 

 

 

 

As I see your ILS course is 255. so headwind is about 12kts (180-255=75, 0.9-.75=0.15, 0,15+0.2=0.35, 0.35x31=12). 1/2x12+9=15 . so the value you have to put in should be 15.

And I was so proud to know what I already know about this bird... there's definitely some stuff left in the to do bucket for me :blink:

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19 hours ago, Tom Knudsen said:

 

Ok so rwy metar 18031G40 would be

 

Sent from my SM-G928F using Tapatalk

Boeing recommends to add half of the headwind component + the full gust factor. The minimum additional to the Vref is 5, the maximum is 20 kts.

So the additional for you would have been cos(75deg) * 31/2 + 9 = 4 + 9 = 13. Your approach speed would be Vref (140) + speed additional (13) = 153.

You would fly this value (153) until passing the threshhold, then bleed of the steady wind component but keep the full gust factor. Target touchdown is 149.

Jan

 

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44 minutes ago, donoscar said:

And I was so proud to know what I already know about this bird... there's definitely some stuff left in the to do bucket for me :blink:

There is always something we can learn :P BTW this computation is done in every commercial airliner not just this bird ;)

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2 hours ago, rcfreak07 said:

Jan did it with the actual cosinus. I did it with the rule of thumb. thats why the 2kts difference. But either way is correct ;)

now you're showing off :P

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15 hours ago, Litjan said:

You would fly this value (153) until passing the threshhold, then bleed of the steady wind component but keep the full gust factor. Target touchdown is 149.

Jan

 

Hello Jan,
it may be slightly off topic here, but i was looking quiet a while for some good "translation" of that last "magic" phrase. I cant' imagine how that should work in practice, fighting for the centerline in gusts and bleed 4kts over the threshold 1-2 secs before bleeding the remaining speed during flare. Btw. it seems to be at/below accuracy.

What i've observed is that some pilots when approaching threshold generally closing the throttle by a small ~ 5% (N1) twitch. It leads to a shift of control away from thrust to pitch. Probably to increase the "pointiness" during flare to their flaver, And to avoid/breaking any kind of floating tendency early.
Thanks in advance,
_Michael

 

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Hi Michael,

the "bleeding off" is certainly academic/legal, and a prerequisite for landing-distance-calculations to be legal. The shorter the landing distance in the book, the better the plane sells. So it is advantageous to calculate touchdown with "Vref" instead of the minimum Vtgt of Vref+5.

If you are approaching in high (and usually gusty) winds, it would require you to pretty much retard the thrust levers to idle when crossing the threshhold to bleed off 15kts of speed additional until touchdown. A recipe for disaster, as there would be no instantaneous power available in case of a sudden drop-shear or required go-around (spool times). And usually landing distance is not a factor for the 737, especially not in situations with strong headwinds.

If you approach with a solid speed additional, you will need to fly the plane onto the runway, taking care not to bump the nosewheel first (usually you will fly with Flaps30 to give you a better controllability, anyway (higher speed -> better control, less driftangle). Chop the thrust levers at touchdown.

Jan

 

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