You may recall that, thanks to an issue with faulty sensors in the Boeing 737 Max flight control systems, those planes have been grounded after multiple crashes were found to be related to the issue. Grounded planes are, by definition, not in the air, and as such need to be stored, on the ground, somewhere. In the case of Boeing’s Renton Factory in Washington state, there’s so many grounded planes that some of that ground has to be taken from Boeing’s employee parking lots.