The CU AMAX-DOAS instrument will be deployed on the NOAA Twin Otter along with the NOAA wind lidar in the summer of 2021 for several test flights in preparation for the 2022 CUPIDS project. The NOAA Twin Otter payload during CUPiDS. (A) Proposed measurement geometries of remote sensing instruments above and below the plane. (B) CU radiometers on the Twin Otter. (C) Researchers and instruments during the 2010 CALNEX study. (D) View ports on the CU AMAX-DOAS pylon. (E) Disassembled AMAX pylon. (F) NOAA wind profile lidar.