VMS Help FORTRAN, /CONVERT, FDX  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Specifies that numeric data in unformatted files is in little
  endian integer data of the appropriate size (INTEGER*1, INTEGER*2,
  or INTEGER*4), VAX F_floating for REAL*4 and COMPLEX*8, VAX
  D_floating for REAL*8 and COMPLEX*16, and little-endian IEEE
  X_floating for REAL*16.