diff --git a/gdal/frmts/nitf/nitfdataset.cpp b/gdal/frmts/nitf/nitfdataset.cpp
index cda655ec849e..7965a4d5e539 100644
--- a/gdal/frmts/nitf/nitfdataset.cpp
+++ b/gdal/frmts/nitf/nitfdataset.cpp
@@ -4592,6 +4592,12 @@ NITFDataset::NITFCreateCopy(
         GDALWriteRPCTXTFile( pszFilename, papszRPC );
     }
 
+    if( papszRPC != nullptr &&
+        CPLFetchBool(papszFullOptions, "RPCTXT", false))
+    {
+        GDALWriteRPCSensorMLFile( pszFilename, papszRPC );
+    }
+
 /* -------------------------------------------------------------------- */
 /*      Create the output file.                                         */
 /* -------------------------------------------------------------------- */
diff --git a/gdal/gcore/gdal_mdreader.cpp b/gdal/gcore/gdal_mdreader.cpp
index 0e841010c795..7ad1d288603a 100644
--- a/gdal/gcore/gdal_mdreader.cpp
+++ b/gdal/gcore/gdal_mdreader.cpp
@@ -646,6 +646,231 @@ char ** GDALLoadRPCFile( const CPLString& soFilePath )
     return papszMD;
 }
 
+/************************************************************************/
+/*                         GDALWriteRPCSensorMLFile()                        */
+/************************************************************************/
+
+CPLErr GDALWriteRPCSensorMLFile( const char *pszFilename, char **papszMD )
+
+{
+  CPLString osRPCFilename = pszFilename;
+  CPLString soPt(".");
+  size_t found = osRPCFilename.rfind(soPt);
+  if (found == CPLString::npos)
+      return CE_Failure;
+  osRPCFilename.replace (found, osRPCFilename.size() - found, "_RPC_SML.xml");
+  if( papszMD == nullptr )
+  {
+      VSIUnlink(osRPCFilename);
+      return CE_None;
+  }
+
+/* -------------------------------------------------------------------- */
+/*      Read file and parse.                                            */
+/* -------------------------------------------------------------------- */
+  VSILFILE *fp = VSIFOpenL( osRPCFilename, "w" );
+
+  if( fp == nullptr )
+  {
+      CPLError( CE_Failure, CPLE_OpenFailed,
+                "Unable to create %s for writing.\n%s",
+                osRPCFilename.c_str(), CPLGetLastErrorMsg() );
+      return CE_Failure;
+  }
+
+/* -------------------------------------------------------------------- */
+/*      Write RPC values from our RPC metadata.                         */
+/* -------------------------------------------------------------------- */
+  bool bOK = true;
+
+      bOK &= VSIFPrintfL( fp, "<sml:SimpleProcess gml:id=\"model.1\"\n") > 0;
+      bOK &= VSIFPrintfL( fp, "xmlns:sml=\"http://www.opengis.net/sensorml/2.0\"\n") > 0;
+      bOK &= VSIFPrintfL( fp, "xmlns:swe=\"http://www.opengis.net/swe/2.0\"\n") > 0;
+      bOK &= VSIFPrintfL( fp, "xmlns:gml=\"http://www.opengis.net/gml/3.2\"\n") > 0;
+      bOK &= VSIFPrintfL( fp, "xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n") > 0;
+      bOK &= VSIFPrintfL( fp, "xmlns:xlink=\"http://www.w3.org/1999/xlink\"\n") > 0;
+      bOK &= VSIFPrintfL( fp, "xsi:schemaLocation=\"http://www.opengis.net/sensorml/2.0 http://schemas.opengis.net/sensorML/2.0/sensorML.xsd\"\n") > 0;
+      bOK &= VSIFPrintfL( fp, "definition=\"http://www.opengis.net/def/sensor-model/NTB/2.1/NITF/RPC00B\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<gml:identifier codeSpace=\"uid\">urn:ogc:sensor-model:ntb-nitf:2.1:RPC00B</gml:identifier>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:identification>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "    <sml:IdentifierList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        <sml:identifier>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            <sml:Term>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "               <sml:label>TRE</sml:label>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "               <sml:value>RPC00B</sml:value>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            </sml:Term>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        </sml:identifier>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "    </sml:IdentifierList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "</sml:identification>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:classification>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "     <sml:ClassifierList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "         <sml:classifier>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "             <sml:Term definition=\"http://sweetontology.net/reprMathFunction/Polynomial\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "                <sml:label>Math Function Type</sml:label>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "                <sml:value>Rational Polynomial Coefficients</sml:value>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "             </sml:Term>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "         </sml:classifier>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "      </sml:ClassifierList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, " </sml:classification>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:characteristics name=\"ignored\"/>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:inputs>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "    <sml:InputList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        <sml:input name=\"latitude\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            <swe:Quantity definition=\"http://www.opengis.net/def/axis/EPSG/9.9/108\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "                <swe:uom code=\"deg\"/>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            </swe:Quantity>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        </sml:input>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        <sml:input name=\"longitude\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            <swe:Quantity definition=\"http://www.opengis.net/def/axis/EPSG/9.9/109\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "                <swe:uom code=\"deg\"/>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            </swe:Quantity>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        </sml:input>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        <sml:input name=\"altitude\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            <swe:Quantity definition=\"http://www.opengis.net/def/sensor-model-param/xdomes/altitude\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "                <swe:uom code=\"m\"/>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            </swe:Quantity>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        </sml:input>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "    </sml:InputList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "</sml:inputs>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:outputs>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "    <sml:OutputList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "      <sml:output name=\"row\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "          <swe:Quantity definition=\"http://www.opengis.net/def/ogc/Row\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "              <swe:uom code=\"pixel\"/>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "          </swe:Quantity>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "      </sml:output>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        <sml:output name=\"column\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            <swe:Quantity definition=\"http://www.opengis.net/def/ogc/Column\">\n") > 0;
+      bOK &= VSIFPrintfL( fp, "                <swe:uom code=\"pixel\"/>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "            </swe:Quantity>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "        </sml:output>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "    </sml:OutputList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, " </sml:outputs>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:parameters>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:ParameterList>\n") > 0;
+
+  for( int i = 0; apszRPCTXTSingleValItems[i] != nullptr; i ++ )
+  {
+      const char *pszRPCVal = CSLFetchNameValue( papszMD, apszRPCTXTSingleValItems[i] );
+      if( pszRPCVal == nullptr )
+      {
+          CPLError( CE_Failure, CPLE_AppDefined,
+                    "%s field missing in metadata, %s file not written.",
+                    apszRPCTXTSingleValItems[i], osRPCFilename.c_str() );
+          CPL_IGNORE_RET_VAL(VSIFCloseL( fp ));
+          VSIUnlink( osRPCFilename );
+          return CE_Failure;
+      }
+
+      bOK &= VSIFPrintfL( fp, "<sml:parameter name=\"%s\">\n", apszRPCTXTSingleValItems[i]) > 0;
+
+      bOK &= VSIFPrintfL( fp, "  <swe:DataRecord definition=\"http://www.opengis.net/def/sensor-model-param/NTB/2.1/NITF/RPC00B/%s\">\n", apszRPCTXTSingleValItems[i]) > 0;
+      bOK &= VSIFPrintfL( fp, "    <swe:label>NITF RPC00B %s</swe:label>\n", apszRPCTXTSingleValItems[i]) > 0;
+
+      bOK &= VSIFPrintfL( fp, "    <swe:field name=\"%s\"> <swe:Quantity definition=\"http://www.opengis.net/def/sensor-model-param/NTB/2.1/NITF/RPC00B/%s\"><swe:label>%s</swe:label>\n", apszRPCTXTSingleValItems[i], apszRPCTXTSingleValItems[i], apszRPCTXTSingleValItems[i]) > 0;
+
+
+if (strcmp(apszRPCTXTSingleValItems[i],"ERR_BIAS")==0 ||
+    strcmp(apszRPCTXTSingleValItems[i],"ERR_RAND")==0 ||
+    strcmp(apszRPCTXTSingleValItems[i],"HEIGHT_OFF")==0 ||
+    strcmp(apszRPCTXTSingleValItems[i],"HEIGHT_SCALE")==0)
+bOK &= VSIFPrintfL( fp, "    <swe:uom code=\"m\"/>") > 0;
+
+else if (strcmp(apszRPCTXTSingleValItems[i],"LINE_OFF")==0 ||
+strcmp(apszRPCTXTSingleValItems[i],"SAMP_OFF")==0 ||
+strcmp(apszRPCTXTSingleValItems[i],"LINE_SCALE")==0 ||
+strcmp(apszRPCTXTSingleValItems[i],"SAMP_SCALE")==0)
+bOK &= VSIFPrintfL( fp, "    <swe:uom code=\"pixels\"/>") > 0;
+
+else if (strcmp(apszRPCTXTSingleValItems[i],"LAT_OFF")==0 ||
+strcmp(apszRPCTXTSingleValItems[i],"LAT_SCALE")==0 ||
+strcmp(apszRPCTXTSingleValItems[i],"LONG_OFF")==0 ||
+strcmp(apszRPCTXTSingleValItems[i],"LONG_SCALE")==0)
+bOK &= VSIFPrintfL( fp, "    <swe:uom code=\"deg\"/>") > 0;
+
+
+      bOK &= VSIFPrintfL( fp, "<swe:value>%s</swe:value></swe:Quantity></swe:field>\n", pszRPCVal) > 0;
+
+      bOK &= VSIFPrintfL( fp, "  </swe:DataRecord>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "</sml:parameter>\n") > 0;
+  }
+
+
+  // start of DataArray
+
+  for( int i = 0; apszRPCTXT20ValItems[i] != nullptr; i ++ )
+  {
+      const char *pszRPCVal = CSLFetchNameValue( papszMD, apszRPCTXT20ValItems[i] );
+      if( pszRPCVal == nullptr )
+      {
+          CPLError( CE_Failure, CPLE_AppDefined,
+                    "%s field missing in metadata, %s file not written.",
+                    apszRPCTXTSingleValItems[i], osRPCFilename.c_str() );
+          CPL_IGNORE_RET_VAL(VSIFCloseL( fp ));
+          VSIUnlink( osRPCFilename );
+          return CE_Failure;
+      }
+
+      char **papszItems = CSLTokenizeStringComplex( pszRPCVal, " ,",
+                                                        FALSE, FALSE );
+
+      if( CSLCount(papszItems) != 20 )
+      {
+          CPLError( CE_Failure, CPLE_AppDefined,
+                    "%s field is corrupt (not 20 values), %s file not written.\n%s = %s",
+                    apszRPCTXT20ValItems[i], osRPCFilename.c_str(),
+                    apszRPCTXT20ValItems[i], pszRPCVal );
+          CPL_IGNORE_RET_VAL(VSIFCloseL( fp ));
+          VSIUnlink( osRPCFilename );
+          CSLDestroy( papszItems );
+          return CE_Failure;
+      }
+
+
+bOK &= VSIFPrintfL( fp, "            <sml:parameter name=\"%s\">\n", apszRPCTXT20ValItems[i]) > 0;
+bOK &= VSIFPrintfL( fp, "               <swe:DataArray definition=\"http://www.opengis.net/def/sensor-model-param/NTB/2.1/NITF/RPC00B/%s\">\n", apszRPCTXT20ValItems[i]) > 0;
+bOK &= VSIFPrintfL( fp, "                    <swe:elementCount>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                        <swe:Count>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                            <swe:value>20</swe:value>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                        </swe:Count>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                    </swe:elementCount>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                    <swe:elementType name=\"%s\"/>\n", apszRPCTXT20ValItems[i]) > 0;
+bOK &= VSIFPrintfL( fp, "                    <swe:encoding>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                        <swe:TextEncoding tokenSeparator=\" \" blockSeparator=\",\" decimalSeparator=\".\"/>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                    </swe:encoding>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                    <swe:values>\n") > 0;
+
+      for( int j = 0; j < 20; j++ )
+      {
+          bOK &= VSIFPrintfL( fp, "%s ", papszItems[j] ) > 0;
+      }
+
+bOK &= VSIFPrintfL( fp, "                    </swe:values>\n") > 0;
+bOK &= VSIFPrintfL( fp, "                </swe:DataArray>\n") > 0;
+bOK &= VSIFPrintfL( fp, "            </sml:parameter>\n") > 0;
+
+
+
+      CSLDestroy( papszItems );
+  }
+
+
+
+      bOK &= VSIFPrintfL( fp, "</sml:ParameterList>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "</sml:parameters>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:method>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "<sml:ProcessMethod>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "    <swe:description>The RPC00B Tagged Record Extension contains rational function polynomial coefficients and normalization parameters that define the physical relationship between image coordinates and ground coordinates.</swe:description>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "</sml:ProcessMethod>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "</sml:method>\n") > 0;
+      bOK &= VSIFPrintfL( fp, "</sml:SimpleProcess>\n") > 0;
+
+  if( VSIFCloseL( fp ) != 0 )
+      bOK = false;
+
+  return bOK ? CE_None : CE_Failure;
+}
+
 /************************************************************************/
 /*                         GDALWriteRPCTXTFile()                        */
 /************************************************************************/
diff --git a/gdal/gcore/gdal_mdreader.h b/gdal/gcore/gdal_mdreader.h
index 751e2c6142ee..5db01860c70d 100644
--- a/gdal/gcore/gdal_mdreader.h
+++ b/gdal/gcore/gdal_mdreader.h
@@ -216,6 +216,7 @@ bool GDALCheckFileHeader(const CPLString& soFilePath,
 
 CPLErr GDALWriteRPBFile( const char *pszFilename, char **papszMD );
 CPLErr GDALWriteRPCTXTFile( const char *pszFilename, char **papszMD );
+CPLErr GDALWriteRPCSensorMLFile( const char *pszFilename, char **papszMD );
 CPLErr GDALWriteIMDFile( const char *pszFilename, char **papszMD );
 
 #endif //GDAL_MDREADER_H_INCLUDED