REPAIR NAVAID TRESTLE STRUCTURE & INSTALL LIGHTNING PROTECTION

The ILS (Instrument Landing System) is a dual antenna Navigational Aid (NAVAID) system located on Rota's airfield. One of the two antenna systems is situated on a tall, wooden trestle structure a little past the approach end of the runway. This antenna is associated to, but separate from, BLDG 3100. We would like to accomplish the following repairs/modifications to the trestle in order to ensure the safety of the equipment and the personnel who maintain it: 1. Repair deteriorated railings. The railings no longer have the capability to withstand a person's weight and need to be repaired. We would like to maintain the wood material as opposed to incorporating steel so that it does not interfere with the antenna's signal. 2. Treat lumber for the environment. The cross bracing, decking, rails, girders, railings, and beams need to be treated for the environment so that the wood material can withstand the local weather conditions. 3. Reconnect equipment grounding. The equipment ground was discovered to be disconnected and needs to be reconnected in accordance with MIL-HDBK-419 para 2.2.2.2. 4. Install two lightning protection structures on either side of the trestle structure in accordance with MIL-HDBK-419 para 2.2.3. Specific distance and placement restrictions are still being researched. However, we would like the lightning protection to be within the antenna's cone of protection in accordance with MIL-HDBK-419 para 3.5.2. Justification / Impact if not executed This NAVAID system is critical to pilot landing safety. If these repairs are not executed, the equipment could be severely damaged leading to a potential aircraft catastrophe. Additionally, it could lead to the injury or death of the equipment maintainers due to its high elevation.