Various embodiments include a structure configured to at least partially expose a barometric altimeter of an unmanned aerial vehicle (UAV) to air pressure at a location on the UAV where there is reduced pressure perturbations caused by downwash of propellers. The structure may include a proximal portion configured to encompass a barometric altimeter of a circuit board of the UAV. The proximal portion may form at least a partial barrier between the barometric altimeter and a first ambient air pressure that is disturbed by a downwash from propellers of the UAV during flight of the UAV. The structure may also include a distal portion extending away from the barometric altimeter, with the distal portion configured to channel to the barometric altimeter a second ambient air pressure that is disturbed less than the first ambient air pressure by the downwash from propellers of the UAV during flight of the UAV.