This document is the 101H Trench Installation Aircraft (HP Storm) Detail. Pipe detail, charts and notes provide descriptions and measurements.

The detail shows the minimum cover, aggregate base, subbase, final backfill, initial backfill, springline, haunch, bedding, suitable foundation and minimum trench width.

Tables explain the minimum recommended cover for typical aircraft loading and minimum recommended trench widths.

Note 1 states that all pipe systems shall be installed in accordance with ASTM D2321. Note 2 says that measures should be taken to prevent migration of native fines into backfill material. Note 3 explains that the foundation is based on where the trench bottom is unstable. Per the engineer, the trench bottom may be stabilized using a geotextile material. Note 4 is about bedding and suitable material, minimum bedding thickness shall be 4” for 4”-24” or 6” for 30”-60”. Note 5 clarifies that the initial backfill should be of suitable material in accordance with ASTM D2321. Note 6 states that maximum allowable aircraft load at minimum cover depends on the landing gear configuration and the specific pavement section.