Protecting Airport AWOS Systems from Lightning Related Damages

Protecting Airport AWOS Systems from Lightning Related Damages

Published by Kelly Buza on May 10th 2021

Beginning in 2018, Alltec surveyed 29 AWOS sites in the state of South Carolina for goal-oriented grounding systems and lightning protection. Alltec was awarded the honor of being the sole source provider of enhanced grounding systems to the SC Airport AWOS systems. Alltec was contracted to survey, design, and provide products for installation to all SC AWOS sites. With our installation partner – ALP Systems – doing all the installations, we were able to provide a turnkey project from start to finish.

Each project site begins with a site survey which involves an on-site inspection for grounding and surge suppression as well as earth resistivity testing and testing/evaluation of any existing ground systems. Upon completion of the site survey, Alltec provides a report containing test results and proper mitigation recommendations for the airport’s AWOS facilities.

Site plans, grounding drawings and electrical single line diagrams are reviewed. Reports of equipment failures, shutdowns and other lightning related issues are investigated. A visual inspection takes place along with Wenner 4-point soil resistivity testing, and clamp-on testing of any existing ground conductors. The goal is to reach 10 ohms or less per the AWOS system manufacturer’s guidelines.

Often, no Surge Protection Devices (SPDs) are discovered during the site survey and they are always recommended to complete Alltecs’ recommended pyramid of protection.

At the conclusion of the survey and testing, all of the results are compiled into a comprehensive report containing the recommendation of and types of grounding, lightning and surge protection system requirements to obtain an optimal defense against lightning strikes and surge events.


Alltec quotes not only the survey and design phase of these projects but also the materials and installation, thanks to our long-standing partnership with ALP Systems, who with over 15 years’ experience, is the preferred installer of our products. ALP has an in-depth understanding of airports and all of their sensitive equipment, things that you shouldn’t trust to an inexperienced installer.

Further included in the contract, Alltec performs annual inspections of the installed equipment, ensuring that it is in proper working order and will provide maintenance/repairs as needed.

To date, of the 29 Airports in South Carolina for which Alltec provided these services, none have reported experiencing lightning related damages or downtime of their pad mounted AWOS equipment since the installation of systems discussed above.

Alltec recently received an approval letter from the North Carolina DOT that acknowledges us as a Prime contractor for similar AWOS system projects for the next year. This designation essentially gives NC airports a direct line to do business with us and receive the same turnkey service that the South Carolina airports have received.