FSX PMDG Boeing 737 NGX Tutorial. This is a pdf tutorial intended for use with PMDG's Boeing 737NGX product. Instructions within are specific to the PMDG product, but you may be able to use it with other 737NG-type add-on airplanes. The intended audience ranges from those that are completely new to Boeing-type add-ons in FSX, to those who know how to get in the air and land, but would like a more solid understanding of the airplane and its systems. Compared to the extensive documentation that comes with the NGX, the main difference is that this tutorial is designed to be read sequentially rather than to be used as a reference. By Tom Risager.