The PLAIT algorithm ``combine'' two spectra cubes resulting from OTF observation with orthogonal scanning directions into a single spectra cube. It works in the Fourier plane and it reduces the striping due to receiver and atmospheric instabilities which inevitably show up in OTF maps. A version of this algorithm has been implemented as a GILDAS task named PLAIT from a previous version by C.Nieten (itself elaborated on original ideas from the NOD2 package).