First-pass reduction of KPNO/FLAMINGOS Ks-band data for the GOODS HDF-N field, taken on UT 10 Feb 2001. ... It uses a 2048 x 2048 HgCdTe detector and provides a 10'.8 x 10'.8 field of view on the KPNO 4m Mayall telescope. ... The FLAMINGOS fields were separated by roughly 6 arcmin, with 4 arcmin overlap strip between them. The exposure time for this Ks image is approximately 130 minutes per position (doubled in the overlap region). Seeing on UT 10 Feb 2001 was mediocre, roughly 1".5 FWHM. ...