What Serial Number did the factory change from CBS-4 to CBS-5?
Looking through Rotorspot's
Complete (Historical) Civil Rotorcraft Register of Germany (see
Part1 and
Part 2), it would appear as if the "official" change-over took place between Serial Numbers S-888 and S-889:
D-HFNT..... Bölkow 105CBS-4..... S-888..... D-HFNT,D-HMBN[6],P-725(A6) ·
D-HFNU..... Bölkow 105CBS-5..... S-889..... D-HFNU,...(A9C)
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