General aviation pilot reported that their passenger saw a UAS pass near by their aircraft at 1;800 ft AGL. The reporting pilot did not see the UAS and the flight continued normally.

Narrative

Was flying VFR on a sightseeing trip around Michigan and had a near miss with a small hobby drone that was far higher than allowed. I (the PIC) did not spot the drone but it was spotted by the passenger sitting in the right seat. The passenger described the drone as being close enough to see the individual rotors clearly (it seems to have been the common four rotor type of drone similar to the ones sold by DJI) and could make out the individual lights on the drone clearly). The aircraft I was flying was at 2;500 ft MSL at the time (roughly 1;800 ft AGL). The passenger's guess was that the drone was within 100 feet vertically (below) and 200 feet horizontally (to the right). Note that the passenger is not a pilot but that the passenger being close enough to make out the individual components of the drone would indicate that it was very close. Despite my scan for traffic; I was not able to spot the drone before or after the encounter. The passenger said he only saw it because he happened to be looking in the right direction at the right time. From my understanding drones are limited to 400 feet AGL; this drone was far higher than that and in violation of the regulations. Many drones now feature a software limit to prevent them from flying higher than that which would suggest that the drone was purposefully flashed with software intended to break the height regulations.