As SpaceX gears up for a planned 200-meter “hop” of its Starhopper prototype as early as Friday, the Federal Aviation Administration has issued a Notice to Airman (NOTAM) prohibiting aircraft operations near the company’s Boca Chica site for Aug. 16-18.

The NOTAM is in force between 2 p.m. and midnight on Aug. 16-17 and between 6 p.m. and midnight on Aug. 18, affecting airspace within 1.4 nautical miles of the launch site, from the surface up to and including 8,000 feet above sea level. Cameron County has authorized closures of Boca Chica Beach and S.H. 4 from the beach to Oklahoma Avenue for the same times and dates covered by the NOTAM.

Texas Natural Resources Code Section 61.132 requires approval from the Texas General Land Office before the county can authorize closures for primary launch dates on weekends between Memorial Day and Labor Day. The days of Aug. 17-18 are classified as backup dates, however, making GLO approval unnecessary per the agency’s memorandum of understanding with the county.

SpaceX first hopped the Starhopper on July 25, to a much lower height (about 65 feet) than the flight planned for this week. Starhopper is the company’s initial prototype for the Starship/Super Heavy spacecraft-booster configuration under development with the ultimate goal of making humans interplanetary.

SpaceX broke ground on the Boca Chica site in September 2014 and conducted the first engine tests on Starhopper in early April of this year. Elon Musk, the company’s CEO, said that on Aug. 24 at Boca Chica he plans to give an update on Starship development.

The next step will be a hop of the company’s Mk1 Starship prototype, currently under construction at Boca Chica, to as high as 20 kilometers (more than 12 miles), Musk said last month.