This technique can be implemented in different ways and for different objectives. Thus it was divided in three lessons covering the positioning of plane parts asymmetrically displaced, the building of plane parts asymmetrically shaped and the building of plane parts asymmetrically paired. Seek for the other two lessons at the Tutorials index page.

Lesson Two - the building of plane parts asymmetrically shaped:

For each plane part, the TXT definition file contains a set of arrays with nodes coordinates for both the right and the left half of that part. When the plane is modeled in Plane-Maker, for example in the fuselage editing pane, only the half right cross-section nodes are displaced, and the left ones are automatically set mirrored in relation for the vertical axis.

Fortunately, both left and right nodes values are saved in separate and X-Plane engine renders the plane relaying on the data of these nodes, not forcefully mirroring them. Because this, it is possible to edit these nodes values directly in the TXT and then build any asymmetric part.

Caution: Once the plane is modified and converted back to ACF format it cannot be saved through Plane-Maker because doing so will reset the left half side of each part to be symmetric mirrored for the right side.

How-to steps:

1. Start a fresh ACF file in Plane-Maker (let's call it "left-side.acf") and model the piece you intend to build asymmetric, aiming to shape it based on one of its desired half-body. This will create a symmetric part (as usual). See the following left image;
   
   
2. Start another fresh ACF file in Plane-Maker (let's call this one the "right-side.acf") and do the same of step 1 but now aiming to shape it based on the other half of its desired body. This will too create a symmetric part. See the following right image;
   
   

3. Use the ACF2TXT utility to convert both the ACFs file to TXT format;
   
   
4. Search the TXT file for the set of arrays named "body_XYZ"*. These arrays are tridimensional where the first element relates to the plane's part, the second element relates to each part section and the third element relates to each section node. The values that go along with them are the respectively "X", "Y" and "Z" coordinates for that node;
   
   (*) Once again using the fuselage as an example, the target arrays would be the ones named "body_XYZ[18]".
   
   
5. The node elements #0 and #8 represent that pair in the section editing pane (in Plane-Maker) that is always glued to the left side (vertical axis) of the editing box. Their "X" coordinate must be kept as 0 (zero) and they are also shared between the left and right side of the part section (rib). The node elements from #1 to #7 relates to one side and from #9 to #15 relates to the other side of the part's body;
   
   
6. Copying the values of the arrays elements that define a half-side of any plane's body part* from one TXT file and pasting them in the correspondent arrays elements in the other TXT file will result in having a plane part asymmetrically defined;
   
   (*) For this demonstrator values from array "body_XYZ[18][n][1]" to "body_XYZ[18][n][7]" were copied from "left-side.txt" and pasted into "right-side.txt" file.
   
   
7. Finally convert the merged TXT file back to ACF format. You can even open the modified plane in Plane-Maker and see the results, as shown in the following image, but as usual you cannot save it through Plane-Maker, because doing so will reset all the plane's parts symmetries;
   

Almost everything here done by me: Marcelo M. Marques - codename 31 M.M.M
mmarques@frontier.com.br