Some help please. I have completed my model and am trying to get it to work in FS9.I have used FSDS V2, the model was built with the datum on the aircraft centerline (lateral), 1/4 wing cord (long), and through the line Prop center to tail.It is a tricycle, low wing type so I have used the Mooney as a start point for the dynamics. I have included all reference points in the modelWheels and scrape points.The problem is I cannot get it to work in FS. the model just sits on the runway banging it's tail up and down on the surface.I am sure I have missed the point somewhere and would welcome some help.ThanksJohn

If you switch to slew mode, how does your aircraft act? Does it jump way up off the ground? If so this would indicate something wrong with your gear contact points and gear height. Your aircraft should just barely move up when you switch to slew. Also double check your scrape points and be sure none are lower than the gear points. Try raising them to Zero and working them down till the problem returns then back up.Lou

LouThanks for the reply.Yes when I slew the model leaps off the ground.I will check as you say then post an update.John

Hi LouRight I made sure the scrape points were all ablove the wheels. I set them to zero as advised. The model still bangs it's tail on the runway in a fast rocking movement. When I slew it sits still on the runway.John

John,Could you please copy and paste your contacts section and post it in the forum?Lou

Did you make reference parts in your FSDS2 model - gear.center, gear.right, scrape.front, etc.? before you exported?Felix/FFDSPegasus Aviation Design

FelixYes the gear reference parts were added and the scrape points.John

gear.right 1.273000 4.441000 -4.669000gear.left 1.273000 -4.474000 -4.669000gear.center 7.216000 -0.033000 -4.996000scrape.side 1.771000 15.200000 -1.143000scrape.side.1 1.886000 -15.143000 -1.200000scrape.front 9.314000 -0.171000 -1.600000scrape.rear -13.029000 0.286000 0.171000

the above was the FSDS logThe Below is from the cfg fileand from the cfgcontact_points]point.0=1, 7.22, -0.03, -5.00, 1181.1, 0, 0.523, 33.66, 0.296, 2.5, 0.794, 3.5, 3.5, 0, 165.0, 165.0point.1=1, 1.27, -4.47, -4.67, 1574.8, 1, 0.523, 0.00, 0.286, 2.5, 0.808, 4.7, 4.7, 2, 165.0, 165.0point.2=1, 1.27, 4.44, -4.67, 1574.8, 2, 0.523, 0.00, 0.286, 2.5, 0.808, 5.2, 5.2, 3, 165.0, 165.0point.3 = 2, 1.771, 15.200, -1.143, 1800, 0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0point.4 = 2, 1.886, -15.143, -1.200, 1800, 0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0point.5 = 2, 9.314, -0.171, -1.600, 1800, 0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0point.6 = 2, -13.029, 0.286, 0.171, 1800, 0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0

John,It lools like all of your gear points are in front of the CofG. This would make it fall back on its tall. Your two main gear points should be negative. Have a look at this:http://www.oregon-coast.net/Tutorials/CofG/index.htmLou

LouThank you for the help. I have been through the model and checked all the parts and their axis. I also amended the cfg to better position the reference datum and the static pitch angle.This seems to have cured the problem.Many thanks for all the input