Figure 11-21. - Placememt of mat end ramps.

section. The laying of matting should proceed in one direction only, from one end of the runway. Laying of the guide rail, mats, and related components is as follows:

NOTE: The instructions presented here are for a 96-foot runway, but they are also applicable for a 48-foot runway.

1. Establish the guide rail center line, using a transit.

2. Install the first guide rail with dowel pins facing aft (opposite the direction of laying the guide rails). The first guide rail should be 9 feet in length, NAEC (Naval Air Engineering Center) Part No. 6125354, to prevent alignment of the guide rail joint with the mat joint.

3. Install the next four guide rails (10-foot rail) using spacer seals, NAEC Part No. 414233-1, and gap gauges, NAEC Part No. 414219-1, between the guide rail joints before driving the dowel pins. Check for proper position of the pins in the guide rails, using a pin gauge, NAEC Part No. 414212-1.

NOTE: As the guide rails and mats are being laid, any visible depressions in the grade should be filled in and raked with the applicable hand tools.

4. Insert the transit target, NAEC Part No. 414691-1, in the center slot of the guide rail and preliminary alignment of each rail.

5. Lay the 18-foot section of AM-2 matting, as shown in figure 11-22. Insert the mat-locking bars between the guide rail and the mat. (See fig. 11-23.)

6. Insert the transit target, NAEC Part No. 414691-1, in the center slot of the guide rail and make the final alignment by shifting the five guide rails and attached mats. The guide rails and mats maybe shifted by pounding the edge of the guide rail or mat with a wooden block and a mallet. The guide rail center line should not vary more than 1/4 inch in 50 feet in the horizontal direction nor more than 1/8 inch in 12 feet in the vertical direction as determined by a 12-foot straightedge. The straightedge should be moved in 6-foot increments.