Wheel contact points...

[Fozzer]

Hi all...!
This has been covered before by Roger, (Rollerball) some time ago.... 8)...!
(He even highlighted the numbers)... 8)...!
I even saved the details on my computer... ;D...!
But, as we all know, the dreaded computer crash wipes all this delightful information from our hard drives... :'(...!
So lets try it again... ;)...!
The detail necessary to alter in the Aircraft.cfg text file to move the contact points of the nose and main wheels.
Example:

[contact_points]
point.0=1,22.000000,0.000000,-6.916667,1600,0,0.57,75,0.267838,2.5,0.685009,0.000000,0.000000,0.000000,0.000000,0.000000
point.1=1,-1.083333,-7.25000,-5.916667,1600,1,0.57,0.,0.243469,2.5,0.718429,0.000000,0.000000,2.000000,0.000000,0.000000
point.2=1,-1.083333,7.250000,-5.916667,1600,2,0.57,0.,0.243469,2.5,0.718429,0.000000,0.000000,3.000000,0.000000,0.000000
point.3=2,0.000000,0.000000,0.083333,1574.803150,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,5.000000,0.000000,0.000000
point.4=2,0.000000,0.000000,0.083333,1574.803150,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,6.000000,0.000000,0.000000
static_pitch=1.994019
static_cg_height=5.907364

(In this example the nose wheel is buried in the ground up the the axle).
Which are all the numbers that require altering to raise/lower the nose and/or main wheels to contact the ground surface...?
And do the numbers need to be increased/decreased to raise/lower the wheels..?
Many thanks... 8)...!

Cheers all...!

Paul....(complicated..innit.. ::)...)...LOL...!

The actual aircraft can be seen here to illustrate the point...>>>

http://www.simviation.com/cgi-bin/yabb/ ... 1086790864

[Gnome]

Hi Paul,
The very first line relates to the nosewheel and the value in front  of 1600 is vertical the position of the wheel in relation to the aircraft datum.  (First value is the position ahead of the aircraft 00 datum, probably the CG but not always, the second one it the lateral position of the wheel.)

Try altering the -6 value to -5 and see how much higher the nosewheel is.  If there is too much of a change then alter the figures after the decimal point.  you will need to reload the aircraft when you switch back to FS before you'll see any changes.

[ozzy72]

[contact_points] section
You can configure and adjust the way aircraft reacts to different kinds of contact, including landing gear contact and articulation, braking, steering, and damage accrued through excessive speed.
You can also configure each contact point independently for each aircraft, and there is no limit to the number of points you can add. The data for configuring the points are placed in the [contact_points] section of the aircraft.cfg. When importing an aircraft that does not contain this set of data, the program will generate the data from the .air file the first time the aircraft is loaded, and then write it to the aircraft.cfg.
It may be useful to first look at the .cfg file of an existing aircraft; you can learn a lot from the many developer comments, which are followed by two slashes (//).
Each contact point contains a series of values that define the characteristics of the point, separated by commas. Each point's data set takes the form

[Fozzer]

Hi Ozzy....
I've got a headache now... ...!

LOL...LOL...LOL...!

Cheers Mate... ...!

Paul.

I think I'll try just tilting my monitor... ...!
...or maybe Gnome's suggestion... ...?
...and stick to just doing oil changes on my bike... ...!

[Gnome]

Everything Ozzy has said is correct.
I was just trying to keep it simple.
...and after three large Gins I am very simple.  :#}

[Hagar]

Whoa. There's such a thing as too much information Ozzy old chap. The explanation you posted is very useful but far more than Foz needs to know.

I don't who wrote it out but the guides in all Aircraft.cfg files list the entries starting with 0 (zero). For example:
       //0  Class                        
       //1  Longitudinal Position        (feet)
       //2  Lateral Position             (feet)
       //3  Vertical Position            (feet)
This could be a tad confusing for a beginner.

The exact tweak will vary depending on the aircraft. It's not possible to give general advice. It could take seconds or several hours to figure it out. If I get time I'll have a go at the Trislander myself. If I can fix it, which is by no means certain, I'll post the fix here. It would help to know which sim this is for.

[microlight]

I hutterly agree with the point about too much info! I've just been getting me head around water contact points.

Just to add confusion: when I adjust the vertical position of the wheel contact points, I have to increase the negative number to raise the wheel! So e.g. if -9.5 is the wheel up to its axle in the ground, then -11.5 might well get it out.

Pass the Gordon's, somebody...

[ozzy72]

Sorry chaps, I just love playing with FDs, probably because I can't do any other aspect of aircraft design as I'm about as artistic as a potato

[Hagar]

OK, I've installed the Trislander (to FS2002) had a quick tweak. Please try replacing point.0 under the [contact_points] section with this line.

point.0=1,22.000000,0.000000,-6.916667,1600,0,0.57,75,0.25,1.5,0.95,0.000000,0.000000,0.000000,0.000000,0.000000

The nosewheel is the correct height above ground & doesn't need changing. Basically, I've reduced the static compression & increased the damping value. The trick is to do this without making it too springy. The nosewheel will partially disappear below the ground under braking. This is quite normal as it's an older FS2000/2 model without animated suspension. Please remember this is only a quick tweak. It's a long time since I've messed around with this stuff

[microlight]

Ah - THAT's why the nosewheel disappears under braking sometimes! Thanks, Doug.

[ubalmoral]

Great info on the contact points. I'm going to see if I can use it to get rid of a problem I have with a Grumman Albatross.
If you set the parking brake and run up the engines a little, not only the nose gear, but the entire nose sinks into the ground.
Forget about LANDING the thing.
Paul Shell