A remote pilot plans a survey flight at 350 feet AGL in an area where the sectional shows a shaded magenta area (Class E beginning at 700 feet AGL). What authorization is required, and at what altitude would authorization become necessary?

Why →Shaded magenta (sometimes called 'soft magenta') indicates Class E airspace that begins at 700 feet AGL. Below 700 feet AGL, the airspace is Class G. Part 107 operations up to 400 feet AGL are in Class G. ATC authorization under § 107.41 is required only for Class B, C, D, and surface Class E. Class E that begins at 700 or 1,200 AGL does not require authorization for typical sub-400-foot drone operations.

The trap →Requiring LAANC at any altitude misreads shaded magenta as a surface-area indicator. The answer claiming authorization is never required is partially right on the 'uncontrolled' point but misses that Class E is controlled airspace; it just has different authorization requirements under Part 107.

Field note →Most of the continental United States outside dense urban and airport areas is shaded magenta. If you never fly above 400 feet AGL, you rarely need to think about Class E beginning at 700 AGL at all.