Some Hawk bands are noisy to the point of uselessness. For example band 71 (1403nm), raw data from Nigg Bay line 3 (attached)

Also see over-water spectrum produced in level 3 image:

Spectrum cannot really be used for anything much - there is no means of quality controlling the data

Data issue occurs over more than one flight, possibly there are sensor problems with some Hawk bands. See eg. Latera band 71, similar to Nigg Bay:

Hawk imagery since the start of 2009 contain dark stripes running along-track. Initially there was just one stripe but following the instrument's return to Specim in April there has been a number.

On examination, the Hawk spectral calibration appears to have shifted between 2009 and 2010. However, when processing using the new, shifted calibration, we see absorption features misplaced by the same amount as the shift.

This implies the spectral calibration is incorrect.