(2) The relatively high degree of scattering of the measured RTI values from
detector C, D, and E, as mentioned in item 1, could be related to (i) the
sensitivity associated with the detector orientation with respect to the oncoming
plunge-tunnel air flow, and or (ii) the boundary layer effect associated with the
detector frame. Detector Types C, D, and E all have frames, and some detectors’
heat sensing parts were very close to the center cover of the frames.