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PSX + X-Plane for scenery

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Moderator
Registered: May 2009
Posts: 5140
PSX's main gear touches the ground at ca. 0 RA.

PSX's main gear is completely (untilted) on the ground at ca. -2 to -4 RA.

PSX's nose gear is on the ground at ca. -6 to -8 RA, depending on gross weight and strut compression.
Member
Registered: Jun 2009
Posts: 187
Location: Devon, UK
If you give me an ILS where this happens, I will have a look at it.
Member
Registered: Mar 2015
Posts: 47
It happens on all runways (at least where I have flown. EGLL 09L, ENGM 01L, LTBA 23). I think the problem might be that the animation of the main gears is not done in the X-Plane plane and the gears don't "bend"?
Member
Registered: Mar 2015
Posts: 47
Also I have tried to disable sloped runways on X-Plane and it did not help.
Moderator
Registered: May 2009
Posts: 5140
Re nose gear collapse problem:

http://aerowinx.com/forum/topic.php?id=2782
Member
Registered: Mar 2015
Posts: 47
mikeindevon wrote
Yes, you can help. There are a few questions to save me doing the research. How does X-Plane and IVAO interact: is there a plug-in for it? What precisely are the variables you need? If you know the datarefs for them that would be even better.

One problem that we may face is that some XP variables are read only.

Mike


I have now found the person who knows about X-IvAp (the interface between X-Plane and IVAO, and have sent him mail. But already now I can tell that X-IvAp indeed is a plugin inside X-Plane. I will come back when he has answered :).
Member
Registered: Jun 2009
Posts: 187
Location: Devon, UK
Hi Matchball,

Regarding the touchdown issue, have a look at the attached picture that was taken on the Basic 022 situation with the current version of XView..

User posted image

When X-View detects touchdown it compresses the gear to the full up position with the wheels untilted. This hasn't happened yet in this flight so XView is still flying. The PSX RA is showing 2, which is more or less in line with Hardy's note above. Also note that rollout has begun, so PSX has landed, but XView not quite.

Can you be more specific about the issue you are having. What readings on the instrumentation are you using to say that PSX has touched down?

Note: The PSX Plane gear does compress on landing by about one wheel diameter from the flying position. This is done in one step: it is either uncompressed or fully compressed. I could do the compression in stages, the gear model allows for that, but as it all happens so fast I didn't think it was worth the trouble.

Mike
Moderator
Registered: May 2009
Posts: 5140
Hi Mike.

mikeindevon wrote
Also note that rollout has begun, so PSX has landed ...

PSX has not landed yet (not untilted yet). ROLLOUT engages at 5 ft RA in the air.

PSX has landed when you hear the click sound from the gear lock override solenoid (the speedbrake lever sound follows immediately).


Cheers,

|-|ardy
Member
Registered: Mar 2015
Posts: 47
Hardy Heinlin wrote
Hi Mike.

mikeindevon wrote
Also note that rollout has begun, so PSX has landed ...

PSX has not landed yet (not untilted yet). ROLLOUT engages at 5 ft RA in the air.

PSX has landed when you hear the click sound from the gear lock override solenoid (the speedbrake lever sound follows immediately).


Cheers,

|-|ardy


That sound is the one where I have based the idea of PSX touching down. :-)
« Last edit by matchball on Fri, 03 Apr 2015 18:20:00 +0000. »
Moderator
Registered: May 2009
Posts: 5140
"Touch-down" is really a matter of definition.

In an ideal case, the first touch occurs on 8 main wheels, i.e. the rear wheel pairs on each tilted 4-pack.

For most avionic devices that have an air and a ground status, the ground status is set when all 16 main wheels are on the ground; that is, when all 4-packs are untilted. That status I would call "the queen has landed". (And the nose wheel pair is still in the air).
Member
Registered: Mar 2015
Posts: 47
One thing also where this can be noticed is at takeoff. Because the PSX plane already indicates positive rate but in X-Plane the plane jumps up fast after couple seconds.
Member
Registered: Jun 2014
Posts: 317
I noticed that too, it always looks like a tailstrike.
Member
Registered: Jul 2014
Posts: 50
Location: Basel, CH
I've also noticed this 'jump up' in FSX on occasions.
Member
Registered: Jun 2009
Posts: 187
Location: Devon, UK
A bit of background detail.

X-Plane and PSX have a slightly different terrain elevation models. In particular XP has sloping runways. XView feeds into PSX the scenery elevation every few frames, but because of damping in PSX, this elevation data does not immediately affect the elevation within PSX. When the plane is on the ground, this can lead to the plane's image in X-Plane ploughing into the ground especially on upward sloping runways. This doesn't look good.

Also, although PSX is fed the elevation, it knows nothing about the slope of the terrain, either along the line of the plane or perpendicular to it. This again can lead to problems with say the main wheels on the ground and the nosewheel below it.

The approach I took to avoid these problems was to set the plane's elevation to the XP ground elevation when I deemed the plane to have landed. That is I ignored the elevation reported by PSX. I also added the terrain's slope to the attitude (and roll) of the plane. In this way the plane is always position correctly when on the ground and follows the slope exactly, although there is some small damping to smooth out XP's abrupt changes in slope. In fact you can taxi the plane up the side of a mountain and the wheels will remain on the ground whatever the slope.

So in summary, XView uses the PSX elevation when flying and the XP scenery elevation when on or very near (< 0.5m) the ground. These slight jumps or early landings are a side effect of XView swapping between the two modes.

There is a setting within XView that specifies the distance between the base of the landing gear and the plane's centre of gravity. To change this needs a recompilation. If I alter it there is a risk that the plane will appear to plough into the ground. When I developed XView I chose a compromise to ensure that this didn't happen. The price we pay is some slight discontinuities.

I hope this clarifies the situation.

Mike
Member
Registered: Jun 2014
Posts: 317
Thank you for your detailed explanation. Unfortunately it does look odd on a full size flightdeck so customers wont get a realsitc experience. From my expereince, the landing seem to be OK but I'm not a real 747 pilot so cannot comment. Thank you very much for your efforts and hopefully there might be a workaround in the future.
Moderator
Registered: May 2009
Posts: 5140
Member
Registered: Mar 2015
Posts: 47
Has anyone been able to fly online using X-Plane? As I tried yesterday VATSIM and had the same problem as in IVAO. No GS data and also no FL data (altitude data is transferred though).
Member
Registered: Jun 2009
Posts: 187
Location: Devon, UK
I believe that X-Plane itself should work ok via XSquawkbox. This latter software must take internals from X-Plane to provide GS and FL. My problem is that I am unable to set these internal variables via the SDK.

If the guys at IVAO could expose a set of datarefs for these variables, then I could easily write to them.

Mike
Member
Registered: Mar 2015
Posts: 47
What I have found out is that for some reason FL data is not transfferred to the networks but altitude data is? I tried to use the data source to see what alt data does x-plane have but all those figures were frozen.

I am also quite certain that (at least IVAO) plugin takes it data for GS, FL and V/S from the same source as the X-Plane's VC's PFD. As the figures match every single flight.

Please let me know if I can help. I am still trying to find a person who knows about X-IvAp but for now it seems like the person who made the plugin has left the developing department.

Ps. I just wrote again to the software department. I will let you know if I find any info.
Member
Registered: Aug 2011
Posts: 48
Location: Perth
Hi Mike, thankyou for your excellent product, I use it on a daily basis.
Quote
So in summary, XView uses the PSX elevation when flying and the XP scenery elevation when on or very near (< 0.5m) the ground. These slight jumps or early landings are a side effect of XView swapping between the two modes.


Would it be possible to blend the transition between modes?
I am sure you have thought about it, and it may be very complex, I have no idea on that part. It would however, make a great addition to not have the jumping.

Regards
Greg
Member
Registered: Aug 2014
Posts: 95
Hi, Mike and Matchball,

I have found this topic in the X-plane.org forum :
http://forums.x-plane.org/index.php?showtopic=52138

Maybe it could help to calculate the groundspeed in XPX to be used by XView and X-Ivap ?

and there are some VARs in section "sim/flightmodel/position/" from this link :
http://www.xsquawkbox.net/xpsdk/docs/DataRefs.html

I am not an expert in XPX datarefs. I hope it could help. I really wish we could fly correctly on IVAO with PSX and XView.

Stephane
Member
Registered: Jun 2015
Posts: 1
Hi Mike

I've read with interest you post on PSX + X-plane for scenery. Unfortunately Im running PSX on an iMac and I note it's windows based. Are their any plans to make an IOS version?

Thanks in advance

Steve Beckett
Member
Registered: Jun 2009
Posts: 187
Location: Devon, UK
You will find an OS X version at:

ftp://larkshayes.com/Release 1.2/mac.xpl

Access to this site is explained in a previous post.

I would be interested to know if that works for you. It was compiled using the OS X c++ library, which doesn't seem to be available on some user systems. If it doesn't work I will produce a build with the library linked in if I can work out how to get XCode to do that.

Mike
Member
Registered: Jun 2009
Posts: 187
Location: Devon, UK
... specifically it needs "libc++"
Member
Registered: Aug 2014
Posts: 77
Mike,

some months ago I posted about not having the strobe and beacon lights working on your model.

Yesterday I started to debug crash issues with X-Plane and installed a second copy without any addons besides xView. I found at least one error in my sceneries and, purely by accident, found out the following:

If I have a PSX Plane loaded (with the xView plugin) and I change the aircraft to PSX Plane (causing X-Plane to reload the aircraft) the strobes and beacons start working.
Weird, huh?

Now I just have to remember to load the plane twice before starting the APU. :D

Cheers,
Bernd

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