You need execute permission to run an executable file, so you need to mount the ntfs drive with execute permission for that, it is not enough with read/write permissions. An alternative is not to keep linux executables on a file system, that belongs to Windows. Instead you can have an ext file system (for example ext3 on a separate partition on your external drive).
Mount options for ntfs
Character set to use when returning file names. Unlike VFAT,
NTFS suppresses names that contain unconvertible characters.
New name for the option earlier called iocharset.
utf8 Use UTF-8 for converting file names.
For 0 (or `no' or `false'), do not use escape sequences for
unknown Unicode characters. For 1 (or `yes' or `true') or 2,
use vfat-style 4-byte escape sequences starting with ":". Here 2
give a little-endian encoding and 1 a byteswapped bigendian
If enabled (posix=1), the filesystem distinguishes between upper
and lower case. The 8.3 alias names are presented as hard links
instead of being suppressed. This option is obsolete.
uid=value, gid=value and umask=value
Set the file permission on the filesystem. The umask value is
given in octal. By default, the files are owned by root and not
readable by somebody else.