FAA Part 107 Remote Pilot (UAG)OperationsHard
A sectional chart's UAS Facility Map grid indicates a maximum authorized altitude of 1,200 feet MSL for the area where a remote pilot plans to operate. The ground elevation at the launch site is 850 feet MSL. What is the maximum altitude, in feet above ground level, the sUAS may fly to remain within this authorization?
- A1,200 feet AGL
- B350 feet AGL
- C850 feet AGL
- D400 feet AGL
Show answer & explanationAnswer & explanation
Correct answer: B. 350 feet AGL
The maximum authorized altitude is given in MSL, so the AGL limit must be found by subtracting the ground elevation from the authorized MSL altitude: 1,200 ft MSL − 850 ft MSL = 350 ft AGL. This is lower than the standard 400-foot AGL limit, so the pilot must not exceed 350 feet AGL at this location.
Why the other options are wrong
- A. This confuses the MSL ceiling with an AGL altitude.
- C. This is simply the ground elevation, not the usable altitude.
- D. 400 feet AGL exceeds the authorized ceiling in this grid and is not permitted here.
MSL to AGL Conversion
UAS Facility Map grids display maximum authorized altitudes in MSL; pilots must subtract ground elevation to determine the equivalent AGL limit for their location.
- Authorized altitudes on facility maps are given in MSL
- AGL = Authorized MSL altitude − ground elevation MSL
- Actual limit may be lower than the standard 400 ft AGL
Memory trick: 'MSL minus ground equals what you've got (AGL).'