FAA 1A & 2C Certifications

When building tall structures, like cell towers, the Federal Aviation Administration (FAA) requires documentation of the proposed structures height as part of their "aeronautical study process."  During this process, the FAA may request a "certified survey with an accuracy of either 1A (+20 ft horizontally +3ft vertically) or 2C (+50 ft horizontally +20 ft vertically)" per their Survey Accuracy standards.