HB 531-1989
rings (English Version)
- Standard No.
- HB 531-1989
- Language
- Chinese, Available in English version
- Release Date
- 1989
- Published By
- Professional Standard - Aviation
- Latest
- HB 531-1989
HB 531-1989 history
- 1989 HB 531-1989 rings
- 1970 HB 531-1974 rings
