Angel Aircraft

I've been creating a model of the Angel Aircraft for FS9. I have the model nearly complete, but I can't seem to get the flight dynamics to work properly.
I used AirWrench to create the airfile, using the information found here and in this PDF.
Every time I start it, I can't seem to get it into the air. It gets up to speed, but the nose stays glued to the ground. The only way I can get it to fly is to slew it up in the air and then apply massive elevator trim.
What could be the cause?
I used AirWrench to create the airfile, using the information found here and in this PDF.
Every time I start it, I can't seem to get it into the air. It gets up to speed, but the nose stays glued to the ground. The only way I can get it to fly is to slew it up in the air and then apply massive elevator trim.
What could be the cause?
