Airport Imaginary Surfaces 101

Airport Consultants Council


Tuesday, August 8, 2017
1 p.m. - 2:30 p.m. EDT

CM | 1.50

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This ACC Institute 101 online training program will provide an overview of the activities and construction near airports and meeting FAA criteria to prevent obstructions to flight operations. The risks are not only potential collisions between aircraft and obstacles, but obstructions to visual aids (PAPI or VASI) – as well as perturbations of radio-navigational aids and communication signals – can endanger flight operations.

Participants will learn more about Obstacle Limitation Surfaces (OLS) – also known as FAR Part 77 imaginary surfaces – which are designed for planning purposes. Presenters will discuss how they offer larger margins than the U.S. Standard for Terminal Instrument Procedures (TERPS), which define tighter, risk-based surfaces protecting flight operations.

This ACC Institute 101 training program will also review how other protections limit vertical constructions to avoid perturbations of navigational aids (NAVAIDS) and meteorological sensors, and the concept of sight line clearance that ensures Air Traffic Control Towers shall have direct visual contact with aircraft operations.


At the end of this ACC Institute online training program, participants will be able to:

•    Distinguish the difference between FAR Part 77 and the U.S. Standard TERPS.

•    Summarize the critical slopes/areas for navigational and communications aids.

•    Explain the FAA and airport construction airspace notification requirements.

•    Identify the different FAA reference document resources and processes.

Resource URL


Raymond Zee, P.E.

Raymond Zee, P.E., is a Civil Engineer/Airport Airspace Specialist with the Federal Aviation Administration (FAA), Airport Engineering Division, Office of Airport Safety and Standards. Mr. Zee has been with the FAA's Airport Engineering Division for eight years, and his responsibilities include TALPA, runway friction/grooving, friction research ... Read More

Mark Kuttrus, AICP


Contact Info

Lisa Deyo,