diff --git a/libraries/AP_Filesystem/AP_Filesystem_FATFS.cpp b/libraries/AP_Filesystem/AP_Filesystem_FATFS.cpp
index 99735ea72a..db4e1ef18b 100644
--- a/libraries/AP_Filesystem/AP_Filesystem_FATFS.cpp
+++ b/libraries/AP_Filesystem/AP_Filesystem_FATFS.cpp
@@ -47,14 +47,6 @@ typedef struct {
 #define MAX_FILES 16
 static FAT_FILE *file_table[MAX_FILES];
 
-static bool isatty_(int fileno)
-{
-    if (fileno >= 0 && fileno <= 2) {
-        return true;
-    }
-    return false;
-}
-
 /*
   allocate a file descriptor
 */
@@ -65,9 +57,6 @@ static int new_file_descriptor(const char *pathname)
     FIL *fh;
 
     for (i=0; i<MAX_FILES; ++i) {
-        if (isatty_(i)) {
-            continue;
-        }
         if (file_table[i] == NULL) {
             stream = (FAT_FILE *) calloc(sizeof(FAT_FILE),1);
             if (stream == NULL) {
@@ -120,11 +109,6 @@ static int free_file_descriptor(int fileno)
     FAT_FILE *stream;
     FIL *fh;
 
-    if (isatty_( fileno )) {
-        errno = EBADF;
-        return -1;
-    }
-
     // checks if fileno out of bounds
     stream = fileno_to_stream(fileno);
     if (stream == nullptr) {
@@ -150,11 +134,6 @@ static FIL *fileno_to_fatfs(int fileno)
     FAT_FILE *stream;
     FIL *fh;
 
-    if (isatty_(fileno)) {
-        errno = EBADF;
-        return nullptr;
-    }
-
     // checks if fileno out of bounds
     stream = fileno_to_stream(fileno);
     if (stream == nullptr) {
@@ -538,9 +517,6 @@ off_t AP_Filesystem_FATFS::lseek(int fileno, off_t position, int whence)
         errno = EMFILE;
         return -1;
     }
-    if (isatty_(fileno)) {
-        return -1;
-    }
 
     if (whence == SEEK_END) {
         position += f_size(fh);