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

  Specifies that numeric data in unformatted files is in big endian
  integer data of the appropriate size (INTEGER*1, INTEGER*2, or
  INTEGER*4) and CRAY floating-point data of size REAL*8 or
  COMPLEX*16.  REAL*4, REAL*16, and COMPLEX*8 data is not converted.