I would like to create a flt (floating point raster) with QGIS to use later as a terrain in Hec RAS RAS-Mapper. With Raster -> Conversion -> Translate there is no option to create a flt. Is there another way?
Save your raster as ESRI .hdr aka "BIL" format with datatype as float32 and file extension as ".flt".
To output an raster with data type integer as of type float use the raster calculator.
- execute the trivial expression
"raster@band_no" * 1.0(replace raster@band_no with an appropriate value or simply double click the entry in the raster channel list)
- save the output in a format, that supports floating point values, eg GeoTIFF