At what altitude, if any, may an ultralight overfly the Gallup, New Mexico airport (KGUP) with no prior authorization without violating FAR 103.17?
This is a question about the meaning of
"within the lateral boundaries of the surface area."
FAR 103.17 --
"No person may operate an ultralight vehicle within Class A, Class B, Class C, or Class D airspace or within the lateral boundaries of the surface area of Class E airspace designated for an airport unless that person has prior authorization from the ATC facility having jurisdiction over that airspace."
Description of the E2 airspace at KGUP-- from page E-116 of the FAA's "Airspace Designations and Reporting Points" document FAA Order 7400.11D--
"ASW NM E2 Gallup, NM Gallup Municipal Airport, NM (lat. 35°30'41"N., long. 108°47'15"W.) Gallup VORTAC (lat. 35°28'34"N., long. 108°52'21"W.)
Within a 4.1-mile radius of Gallup Municipal Airport and within 1.3 miles each side of the 242° radial of the Gallup VORTAC extending from the 4.1-mile radius to 4.9 miles southwest of the airport."
Note that no limitation is given as to the time of day that the E2 airspace is in effect, and therefore it is in effect 24/7. No specific altitude limit is stated in this section, though on page E-1 we read--
Generally, if the airspace is not Class A, Class B, Class C, or Class D, and it is controlled airspace, it is Class E airspace. Class E airspace extends upward from either the surface or a designated altitude to the overlying or adjacent controlled airspace. When designated as a surface area, the airspace will be configured to contain all instrument procedures. Also in this class are Federal airways, airspace beginning at either 700 or 1,200 feet above ground level used to transition to/from the terminal or enroute environment, and enroute domestic and offshore airspace areas designated below 18,000 feet MSL. Class E airspace does not include the airspace 18,000 feet MSL or above.