Spoileron movements when spoilers deployed

[Capt. Windh 3]

So far only one person has said they haven't seen it happen on their system. I'll test it on mine when I can and let you know what I see.

 

However, as far as I'm aware there's no reason why the wheel would not affect spoiler position on ground just as it does in the air. It just shouldn't be as much as you see, which is due to the error in the NGX model.

Ok, cheers. Perhaps there's a way to minimize it at least then.

[kevinh 409]

Ok, cheers. Perhaps there's a way to minimize it at least then.

I see exactly what you do.  The ground spoilers do not move, which is correct, but the flight spoilers move in the same way they do in the air.  If you turn the wheel slightly left, the right spoilers fully retract (wrong), the left spoilers increase angle a little (correct).  This is of course wrong, but it's an error in the NGX wing surfaces modelling that's been there since launch day.

 

My understanding of the aircraft system is that on ground with speedbrake extended fully, the flight spoilers deflect partially and should still modulate with wheel input, as they do in flight.  However the ground spoilers go to full deflection and are not affected by wheel position.

[Spin737 102]

 

 

My understanding of the aircraft system is that on ground with speedbrake extended fully, the flight spoilers deflect partially and should still modulate with wheel input, as they do in flight. However the ground spoilers go to full deflection and are not affected by wheel position.

I had to dig in the books, and I might again, but I thought that with the speedbrakes up, they all go up to their maximum deflection.

[kjjj11223344 48]

Are you guys using FSrecorder to see this? I've never seen this in any of the replays I've done with FSrecorder. To the OP: are you steering with the yoke on the ground since you have autorudder enabled? If yes, then that would explain why I'm not seeing this.

[Capt. Windh 3]

Yep, I use the yoke to steer on the ground. But just after touchdown you would still use aerodynamic control together with the nose wheel to steer the acft until it settles filly, so this *should* affect people with pedals too.

 

I can reproduce this in both fsrecorder and 'live'.

[Capt. Windh 3]

Here's another video, with both the wings and the VC-yoke in frame, so you'll see the amount of input.

 

This is "live" and with only keyboard assigned to control the ailerons.

 

First with spoilers down and then with speedbrakes fully extended in ground mode.

 

https://vimeo.com/74512274

[kevinh 409]

I had to dig in the books, and I might again, but I thought that with the speedbrakes up, they all go up to their maximum deflection.

I thought I had some NG simulator design data available for spoilers, but it turned out to be for the 737 Classic.  That clearly shows that roll spoilers operate on the ground.  The flight spoilers don't deflect as much as the ground spoilers which gives them the ability to deflect more if a roll input is applied (and of course less on the other wing).  I don't know whether this is a difference between the Classic and the NG, but although the spoiler systems are different I doubt whether something as basic as this would have been changed. According to this website, the NG flight spoilers are similarly limited in the full UP position (33 and 38 degrees for flight spoilers, 52 and 60 degrees for ground spoilers). The site doesn't say whether the roll spoilers should operate on ground or not in the NG, but the photos certainly confirm this was the case for the Classic.

 

My guess is that some people aren't seeing this on the NGX because they aren't holding in crosswind wheel inputs after landing or steering with the wheel. However it's very easy to see the effect if you deploy the speedbrake and move the wheel.  I'm sure this is related to the way PMDG have used a statement in the FCOM about roll spoilers staying faired with the wing on the up going side and assumed this also applies with speedbrake extended, which it does not. The sudden asymmetry this would create would cause a handling issue in the real thing, I suspect.

[Capt. Windh 3]

Interesting findings Kevin. Thanks.

 

I've been looking at Real World NG crosswind landings (wingviews) on youtube and not seen any of them having the spoilerons move after touchdown, they stay at fully deployed. 

 

Watching some FS-videos of the NGX I find that some people have these issues and some don't, as predicted.

 

The question remains though.. Is there a way to fix/tweak this? Or at least make the spoilerons' movements less sensitive?

[kjjj11223344 48]

Yep, I use the yoke to steer on the ground. But just after touchdown you would still use aerodynamic control together with the nose wheel to steer the acft until it settles filly, so this *should* affect people with pedals too.

 

I can reproduce this in both fsrecorder and 'live'.

Alright that makes sense. I don't always watch replays, and the times I have, I don't think that I was correcting for crosswind, etc. But I just performed a crosswind landing to check and do see this effect. Maybe a support ticket should be sent so the team becomes aware of the issue?

[vonmar 125]

Johan,

 

Are you using Spoileron = 737NG Flight Spoiler?

 

 

http://www.b737.org.uk/flightcontrols.htm

 

[Spin737 102]

I'll dig through what I have, but I've done a lot of dead-heading in the exit row (that's usually where they seat crewmembers on DH) and I don't think I've seen any spoiler movement once we touch down. When the spoilers deploy on landing, they're up, and that's it.

[kevinh 409]

I'll dig through what I have, but I've done a lot of dead-heading in the exit row (that's usually where they seat crewmembers on DH) and I don't think I've seen any spoiler movement once we touch down. When the spoilers deploy on landing, they're up, and that's it.

You'd have to move the wheel more than about 10 degrees before getting any movement, which would even then be small.

 

Either way, the NGX isn't right.  Which is no help to Johan of course.

[Capt. Windh 3]

Johan,

 

Are you using Spoileron = 737NG Flight Spoiler?

 

 

http://www.b737.org.uk/flightcontrols.htm

 

 

Hi Vaughan. Not really sure what you mean by this? Cool site anyway!

 

Either way, the NGX isn't right.  Which is no help to Johan of course.

 

Ok, so that's established. It's not a crucial deal, but for someone like me, who enjoy to make FS-videos it simply makes them less realistic. And it that case, it is rather annoying. 

Maybe a support ticket should be sent so the team becomes aware of the issue?

 

Is that done via the PMDG homepage?

[vonmar 125]

Hi Vaughan. Not really sure what you mean by this? Cool site anyway!

 

 

I went to the manual and got a jpg.

 

I was looking for Spoileron .. did not see it.

[kjjj11223344 48]

Is that done via the PMDG homepage?

Yes, I think it is done through the support portal.