diff --git a/src/Main/fg_io.cxx b/src/Main/fg_io.cxx
index e48061401..dca5d3bbf 100644
--- a/src/Main/fg_io.cxx
+++ b/src/Main/fg_io.cxx
@@ -23,21 +23,9 @@
 
 #include <Include/compiler.h>
 
-// #ifdef FG_HAVE_STD_INCLUDES
-// #  include <cmath>
-// #  include <cstdlib>    // atoi()
-// #else
-// #  include <math.h>
-// #  include <stdlib.h>   // atoi()
-// #endif
-
 #include STL_STRING
-// #include STL_IOSTREAM                                           
-// #include <vector>                                                               
 
 #include <Debug/logstream.hxx>
-// #include <Aircraft/aircraft.hxx>
-// #include <Include/fg_constants.h>
 #include <Include/fg_types.hxx>
 #include <Main/options.hxx>
 
@@ -51,7 +39,6 @@
 #include <Network/pve.hxx>
 #include <Network/rul.hxx>
 
-// #include <Time/fg_time.hxx>
 #include <Time/timestamp.hxx>
 
 FG_USING_STD(string);
@@ -193,190 +180,6 @@ void fgIOInit() {
 }
 
 
-static void send_fgfs_out( FGIOChannel *p ) {
-}
-
-static void read_fgfs_in( FGIOChannel *p ) {
-}
-
-
-// "RUL" output format (for some sort of motion platform)
-//
-// The Baud rate is 2400 , one start bit, eight data bits, 1 stop bit,
-// no parity.
-//
-// For position it requires a 3-byte data packet defined as follows:
-//
-// First bite: ascII character "P" ( 0x50 or 80 decimal )
-// Second byte X pos. (1-255) 1 being 0* and 255 being 359*
-// Third byte Y pos.( 1-255) 1 being 0* and 255 359*
-//
-// So sending 80 127 127 to the two axis motors will position on 180*
-// The RS- 232 port is a nine pin connector and the only pins used are
-// 3&5.
-
-static void send_rul_out( FGIOChannel *p ) {
-#if 0
-    char rul[256];
-
-    FGInterface *f;
-    FGTime *t;
-
-    f = current_aircraft.fdm_state;
-    t = FGTime::cur_time_params;
-
-    // run as often as possibleonce per second
-
-    // this runs once per second
-    // if ( p->last_time == t->get_cur_time() ) {
-    //    return;
-    // }
-    // p->last_time = t->get_cur_time();
-    // if ( t->get_cur_time() % 2 != 0 ) {
-    //    return;
-    // }
-    
-    // get roll and pitch, convert to degrees
-    double roll_deg = f->get_Phi() * RAD_TO_DEG;
-    while ( roll_deg < -180.0 ) {
-	roll_deg += 360.0;
-    }
-    while ( roll_deg > 180.0 ) {
-	roll_deg -= 360.0;
-    }
-
-    double pitch_deg = f->get_Theta() * RAD_TO_DEG;
-    while ( pitch_deg < -180.0 ) {
-	pitch_deg += 360.0;
-    }
-    while ( pitch_deg > 180.0 ) {
-	pitch_deg -= 360.0;
-    }
-
-    // scale roll and pitch to output format (1 - 255)
-    // straight && level == (128, 128)
-
-    int roll = (int)( (roll_deg+180.0) * 255.0 / 360.0) + 1;
-    int pitch = (int)( (pitch_deg+180.0) * 255.0 / 360.0) + 1;
-
-    sprintf( rul, "p%c%c\n", roll, pitch);
-
-    FG_LOG( FG_IO, FG_INFO, "p " << roll << " " << pitch );
-
-    string rul_sentence = rul;
-    p->port.write_port(rul_sentence);
-#endif
-}
-
-
-// "PVE" (ProVision Entertainment) output format (for some sort of
-// motion platform)
-//
-// Outputs a 5-byte data packet defined as follows:
-//
-// First bite:  ASCII character "P" ( 0x50 or 80 decimal )
-// Second byte:  "roll" value (1-255) 1 being 0* and 255 being 359*
-// Third byte:  "pitch" value (1-255) 1 being 0* and 255 being 359*
-// Fourth byte:  "heave" value (or vertical acceleration?)
-//
-// So sending 80 127 127 to the two axis motors will position on 180*
-// The RS- 232 port is a nine pin connector and the only pins used are
-// 3&5.
-
-static void send_pve_out( FGIOChannel *p ) {
-#if 0
-    char pve[256];
-
-    FGInterface *f;
-    FGTime *t;
-
-
-    f = current_aircraft.fdm_state;
-    t = FGTime::cur_time_params;
-
-    // run as often as possibleonce per second
-
-    // this runs once per second
-    // if ( p->last_time == t->get_cur_time() ) {
-    //    return;
-    // }
-    // p->last_time = t->get_cur_time();
-    // if ( t->get_cur_time() % 2 != 0 ) {
-    //    return;
-    // }
-    
-    // get roll and pitch, convert to degrees
-    double roll_deg = f->get_Phi() * RAD_TO_DEG;
-    while ( roll_deg <= -180.0 ) {
-	roll_deg += 360.0;
-    }
-    while ( roll_deg > 180.0 ) {
-	roll_deg -= 360.0;
-    }
-
-    double pitch_deg = f->get_Theta() * RAD_TO_DEG;
-    while ( pitch_deg <= -180.0 ) {
-	pitch_deg += 360.0;
-    }
-    while ( pitch_deg > 180.0 ) {
-	pitch_deg -= 360.0;
-    }
-
-    short int heave = (int)(f->get_W_body() * 128.0);
-
-    // scale roll and pitch to output format (1 - 255)
-    // straight && level == (128, 128)
-
-    short int roll = (int)(roll_deg * 32768 / 180.0);
-    short int pitch = (int)(pitch_deg * 32768 / 180.0);
-
-    unsigned char roll_b1, roll_b2, pitch_b1, pitch_b2, heave_b1, heave_b2;
-    roll_b1 = roll >> 8;
-    roll_b2 = roll & 0x00ff;
-    pitch_b1 = pitch >> 8;
-    pitch_b2 = pitch & 0x00ff;
-    heave_b1 = heave >> 8;
-    heave_b2 = heave & 0x00ff;
-
-    sprintf( pve, "p%c%c%c%c%c%c\n", 
-	     roll_b1, roll_b2, pitch_b1, pitch_b2, heave_b1, heave_b2 );
-
-    // printf( "p [ %u %u ]  [ %u %u ]  [ %u %u ]\n", 
-    //         roll_b1, roll_b2, pitch_b1, pitch_b2, heave_b1, heave_b2 );
-
-    FG_LOG( FG_IO, FG_INFO, "roll=" << roll << " pitch=" << pitch <<
-	    " heave=" << heave );
-
-    string pve_sentence = pve;
-    p->port.write_port(pve_sentence);
-#endif
-}
-
-
-// one more level of indirection ...
-static void process_port( FGIOChannel *p ) {
-#if 0
-    if ( p->kind == fgIOCHANNEL::FG_SERIAL_NMEA_OUT ) {
-	send_nmea_out(p);
-    } else if ( p->kind == fgIOCHANNEL::FG_SERIAL_NMEA_IN ) {
-	read_nmea_in(p);
-    } else if ( p->kind == fgIOCHANNEL::FG_SERIAL_GARMIN_OUT ) {
-	send_garmin_out(p);
-    } else if ( p->kind == fgIOCHANNEL::FG_SERIAL_GARMIN_IN ) {
-	read_garmin_in(p);
-    } else if ( p->kind == fgIOCHANNEL::FG_SERIAL_FGFS_OUT ) {
-	send_fgfs_out(p);
-    } else if ( p->kind == fgIOCHANNEL::FG_SERIAL_FGFS_IN ) {
-	read_fgfs_in(p);
-    } else if ( p->kind == fgIOCHANNEL::FG_SERIAL_RUL_OUT ) {
-	send_rul_out(p);
-    } else if ( p->kind == fgIOCHANNEL::FG_SERIAL_PVE_OUT ) {
-	send_pve_out(p);
-    }
-#endif
-}
-
-
 // process any serial port work
 void fgIOProcess() {
     FGProtocol *p;
diff --git a/src/Main/fg_io.hxx b/src/Main/fg_io.hxx
index 163d96f07..71a0fd30b 100644
--- a/src/Main/fg_io.hxx
+++ b/src/Main/fg_io.hxx
@@ -27,14 +27,6 @@
 
 #include "Include/compiler.h"
 
-// #include <string>
-
-// #ifdef FG_HAVE_STD_INCLUDES
-// #  include <ctime>
-// #else
-// #  include <time.h>
-// #endif
-
 #include <Network/iochannel.hxx>
 
 
diff --git a/src/Network/fg_serial.cxx b/src/Network/fg_serial.cxx
index 713fdf377..87dcb207e 100644
--- a/src/Network/fg_serial.cxx
+++ b/src/Network/fg_serial.cxx
@@ -23,14 +23,6 @@
 
 #include <Include/compiler.h>
 
-// #ifdef FG_HAVE_STD_INCLUDES
-// #  include <cmath>
-// #  include <cstdlib>    // atoi()
-// #else
-// #  include <math.h>
-// #  include <stdlib.h>   // atoi()
-// #endif
-
 #include STL_STRING
 
 #include <Debug/logstream.hxx>
@@ -39,8 +31,6 @@
 #include <Serial/serial.hxx>
 #include <Time/fg_time.hxx>
 
-// #include "options.hxx"
-
 #include "fg_serial.hxx"
 
 FG_USING_STD(string);
@@ -72,158 +62,6 @@ bool FGSerial::open( FGProtocol::fgProtocolDir dir ) {
 }
 
 
-#if 0
-// "RUL" output format (for some sort of motion platform)
-//
-// The Baud rate is 2400 , one start bit, eight data bits, 1 stop bit,
-// no parity.
-//
-// For position it requires a 3-byte data packet defined as follows:
-//
-// First bite: ascII character "P" ( 0x50 or 80 decimal )
-// Second byte X pos. (1-255) 1 being 0* and 255 being 359*
-// Third byte Y pos.( 1-255) 1 being 0* and 255 359*
-//
-// So sending 80 127 127 to the two axis motors will position on 180*
-// The RS- 232 port is a nine pin connector and the only pins used are
-// 3&5.
-
-static void send_rul_out( fgIOCHANNEL *p ) {
-    char rul[256];
-
-    FGInterface *f;
-    FGTime *t;
-
-    f = current_aircraft.fdm_state;
-    t = FGTime::cur_time_params;
-
-    // run as often as possibleonce per second
-
-    // this runs once per second
-    // if ( p->last_time == t->get_cur_time() ) {
-    //    return;
-    // }
-    // p->last_time = t->get_cur_time();
-    // if ( t->get_cur_time() % 2 != 0 ) {
-    //    return;
-    // }
-    
-    // get roll and pitch, convert to degrees
-    double roll_deg = f->get_Phi() * RAD_TO_DEG;
-    while ( roll_deg < -180.0 ) {
-	roll_deg += 360.0;
-    }
-    while ( roll_deg > 180.0 ) {
-	roll_deg -= 360.0;
-    }
-
-    double pitch_deg = f->get_Theta() * RAD_TO_DEG;
-    while ( pitch_deg < -180.0 ) {
-	pitch_deg += 360.0;
-    }
-    while ( pitch_deg > 180.0 ) {
-	pitch_deg -= 360.0;
-    }
-
-    // scale roll and pitch to output format (1 - 255)
-    // straight && level == (128, 128)
-
-    int roll = (int)( (roll_deg+180.0) * 255.0 / 360.0) + 1;
-    int pitch = (int)( (pitch_deg+180.0) * 255.0 / 360.0) + 1;
-
-    sprintf( rul, "p%c%c\n", roll, pitch);
-
-    FG_LOG( FG_IO, FG_INFO, "p " << roll << " " << pitch );
-
-    string rul_sentence = rul;
-    p->port.write_port(rul_sentence);
-}
-
-
-// "PVE" (ProVision Entertainment) output format (for some sort of
-// motion platform)
-//
-// Outputs a 5-byte data packet defined as follows:
-//
-// First bite:  ASCII character "P" ( 0x50 or 80 decimal )
-// Second byte:  "roll" value (1-255) 1 being 0* and 255 being 359*
-// Third byte:  "pitch" value (1-255) 1 being 0* and 255 being 359*
-// Fourth byte:  "heave" value (or vertical acceleration?)
-//
-// So sending 80 127 127 to the two axis motors will position on 180*
-// The RS- 232 port is a nine pin connector and the only pins used are
-// 3&5.
-
-static void send_pve_out( fgIOCHANNEL *p ) {
-    char pve[256];
-
-    FGInterface *f;
-    FGTime *t;
-
-
-    f = current_aircraft.fdm_state;
-    t = FGTime::cur_time_params;
-
-    // run as often as possibleonce per second
-
-    // this runs once per second
-    // if ( p->last_time == t->get_cur_time() ) {
-    //    return;
-    // }
-    // p->last_time = t->get_cur_time();
-    // if ( t->get_cur_time() % 2 != 0 ) {
-    //    return;
-    // }
-    
-    // get roll and pitch, convert to degrees
-    double roll_deg = f->get_Phi() * RAD_TO_DEG;
-    while ( roll_deg <= -180.0 ) {
-	roll_deg += 360.0;
-    }
-    while ( roll_deg > 180.0 ) {
-	roll_deg -= 360.0;
-    }
-
-    double pitch_deg = f->get_Theta() * RAD_TO_DEG;
-    while ( pitch_deg <= -180.0 ) {
-	pitch_deg += 360.0;
-    }
-    while ( pitch_deg > 180.0 ) {
-	pitch_deg -= 360.0;
-    }
-
-    short int heave = (int)(f->get_W_body() * 128.0);
-
-    // scale roll and pitch to output format (1 - 255)
-    // straight && level == (128, 128)
-
-    short int roll = (int)(roll_deg * 32768 / 180.0);
-    short int pitch = (int)(pitch_deg * 32768 / 180.0);
-
-    unsigned char roll_b1, roll_b2, pitch_b1, pitch_b2, heave_b1, heave_b2;
-    roll_b1 = roll >> 8;
-    roll_b2 = roll & 0x00ff;
-    pitch_b1 = pitch >> 8;
-    pitch_b2 = pitch & 0x00ff;
-    heave_b1 = heave >> 8;
-    heave_b2 = heave & 0x00ff;
-
-    sprintf( pve, "p%c%c%c%c%c%c\n", 
-	     roll_b1, roll_b2, pitch_b1, pitch_b2, heave_b1, heave_b2 );
-
-    // printf( "p [ %u %u ]  [ %u %u ]  [ %u %u ]\n", 
-    //         roll_b1, roll_b2, pitch_b1, pitch_b2, heave_b1, heave_b2 );
-
-    FG_LOG( FG_IO, FG_INFO, "roll=" << roll << " pitch=" << pitch <<
-	    " heave=" << heave );
-
-    string pve_sentence = pve;
-    p->port.write_port(pve_sentence);
-}
-
-#endif
-
-
 // read data from port
 bool FGSerial::read( char *buf, int *length ) {
     // read a chunk
diff --git a/src/Network/pve.cxx b/src/Network/pve.cxx
index 2caa94060..f9d3cc8c6 100644
--- a/src/Network/pve.cxx
+++ b/src/Network/pve.cxx
@@ -38,7 +38,16 @@ FGPVE::~FGPVE() {
 }
 
 
-// generate Garmin message
+// "PVE" (ProVision Entertainment) output format (for some sort of
+// motion platform)
+//
+// Outputs a 5-byte data packet defined as follows:
+//
+// First bite:  ASCII character "P" ( 0x50 or 80 decimal )
+// Second byte:  "roll" value (1-255) 1 being 0* and 255 being 359*
+// Third byte:  "pitch" value (1-255) 1 being 0* and 255 being 359*
+// Fourth byte:  "heave" value (or vertical acceleration?)
+
 bool FGPVE::gen_message() {
     // cout << "generating pve message" << endl;
     FGInterface *f = cur_fdm_state;
diff --git a/src/Network/rul.cxx b/src/Network/rul.cxx
index 97f1e9eec..47eb238e9 100644
--- a/src/Network/rul.cxx
+++ b/src/Network/rul.cxx
@@ -39,7 +39,21 @@ FGRUL::~FGRUL() {
 }
 
 
-// generate Garmin message
+// "RUL" output format (for some sort of motion platform)
+//
+// The Baud rate is 2400 , one start bit, eight data bits, 1 stop bit,
+// no parity.
+//
+// For position it requires a 3-byte data packet defined as follows:
+//
+// First bite: ascII character "P" ( 0x50 or 80 decimal )
+// Second byte X pos. (1-255) 1 being 0* and 255 being 359*
+// Third byte Y pos.( 1-255) 1 being 0* and 255 359*
+//
+// So sending 80 127 127 to the two axis motors will position on 180*
+// The RS- 232 port is a nine pin connector and the only pins used are
+// 3&5.
+
 bool FGRUL::gen_message() {
     // cout << "generating rul message" << endl;
     FGInterface *f = cur_fdm_state;