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OBIO
October 9th, 2008, 14:04
Working on the Alpha Sim A-90 Orlenok and getting it converted. The animations are there, the flight dynamics are there (I guess, have never flown an A-90 Orlenok before...it flies fine, handles well). The problem is the landing gear. The rear gear collapses under the plane. I have tried raising the contact points...but that did nothing. I know there is a way to strengthen the landing gear so it does not smush down...but can't remember which part of the contact point line determines the strength of the landing gear.

OBIO

Also have the SU-47 Berkut converted and flying sweet! Need to regauge the 2D and VC panels.

The Orlenok will have a custom made sound pack to reflect its tail mounted turbo prop and the 2 jet engines in the nose of the plane.

Buddha13
October 9th, 2008, 15:33
Hi Obio,
You need to alter the part of the contact point that say's 2.0 to 250.00
Like this example.See red number.This needs to be altered in contact point 0,1 and 2.It is the tenth number in.The number may vary a little.It may be 2.5.It is 2.0 in this example.
point.0 = 1.000, 30.900, 0.000, -11.900, 2000.000, 0.000, 1.300, 40.000, 0.110, 2.000 , 0.840, 5.000, 5.000, 0.000, 0.000, 0.000
to
point.0 = 1.000, 30.900, 0.000, -11.900, 2000.000, 0.000, 1.300, 40.000, 0.110, 250.000 , 0.840, 5.000, 5.000, 0.000, 0.000, 0.000

Buddha13

OBIO
October 9th, 2008, 16:32
Okay, thanks Buddha. 10th number goes up, gear stops smashing. Got to remember that.

Someplace around there is the SDK thingie that explains the config file, including the contact points fully...but I lost the link to it.

OBIO

Tango_Romeo
October 9th, 2008, 16:55
....Most of the CFS2 stock aircraft CFG files contain a key to the Contact Point numbers. Check it out. :ernae:

OBIO
October 9th, 2008, 18:22
The key I have...but nothing in the key says "if your plane sinks up to its butt in mud, increase this number to 5000".

It actually took a lot more work than that to get the plane to sit fairly well. I had to move the main gear out and back a good bit, lower the contact points all around by several feet and increase the compression from 2.5 to 5000 on the main gear.

It still does not sit 100% properly, but close enough that I don't think any but the most die hard rivet counters will complain too much.

OBIO

Tango_Romeo
October 10th, 2008, 08:57
...the compression ratio. You should not have to increase your compression to a number as high as 5000. Also check your aircraft weight....it could be FUBAR. Just a thought. :wavey:

PSULLYKEYS
October 10th, 2008, 17:47
Try this method..its the best I've ever seen.

http://www.sim-outhouse.com/index.php?loc=articles&page=cp

Good Luck,

dvslats
October 10th, 2008, 18:19
http://www.cfgse.calebflerk.com/CFG_CtcPoints.htm

OBIO
October 10th, 2008, 18:56
The best info I could find on the A-90 gives a dry (empty) weight of 125 tons (250,000 pounds). The weight set in the air file was 275,000 pounds...so I dropped that back to 250,000 pounds. Will fire the bird up and see how she does now.

OBIO

Tango_Romeo
October 11th, 2008, 13:52
.....Flerk:


point.0 = 1, -17.69, 0.00, -3.74, 3200.0, 0, 0.50,180.0, 0.25, 2.5, 0.90, 1.0, 4.00, 0, 0, 200

static_compression. The amount the landing gear strut is compressed in feet when at rest on the ground. This value sets the strength of the landing gear. The smaller the number, the "stiffer" the strut. Adjusting this value for a nose wheel/tail wheel aircraft can fix the "bouncy tail" syndrome.

And I still think your static_compression and compression_ratio may be at odds with each other.

Just a thought.

OBIO
October 11th, 2008, 16:43
Stock Contact Points

point.0 = 1, 30.9491, 0.00, -12.90, 2000, 0.0, 1.44, 40.0, 0.8, 2.5, 0.9, 4, 4, 0, 0, 0
point.1 = 1, -4.00, 7.66, -13.25, 2500, 2.0, 1.44, 0.0, 1.00, 2.5, 0.9, 6.9, 6.9, 2, 0, 0
point.2 = 1, -4.00, -7.66, -13.25, 2500, 1.0, 1.44, 0.0, 1.00, 2.5, 0.90, 6.9, 6.9, 2.0, 0.0, 0.0



Revised Contact Points

point.0= 1, 30.949, 0.000, -13.900, 2000, 0, 1.440, 40.000, 0.800, 62.500, 0.900, 4.000, 4.000, 0
point.1= 1, -15.000, 15.660, -19.500, 2500, 2, 1.440, 0.000, 1.000, 5000.000, 0.900, 6.900, 6.900, 2
point.2= 1, -15.000, -15.660, -19.500, 2500, 1, 1.440, 0.000, 1.000, 5000.000, 0.900, 6.900, 6.900, 2

Will be reverting back to the stock air and cofig files and beginning from the top...beginning by setting the weight of the aircraft to 250,000 pounds instead of 275,000 pounds.

OBIO