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Fokker F.VIIb-3m

The pre-war bestseller.
There is no doubt that the 'Southern Cross' was the most famous of Fokker aircraft. The equally famous Australian aviation pioneer Charles E. Kingsford Smith used this machine around 1930 to make several historical flights. The flights by this and other F.VIIb-3ms, made the design Fokker's best selling pre-war airliner. It has often been said that the F.VIIb-3m was a development of the F.VIIa-3m. However logical this may seem, it is not correct. The two variants were designed almost simultaneously, but the F.VIIb-3m was actually built at a later date. In the November 1925 issue of the 'Fokker Bulletin' magazine, a trimotor version of the F.VII was offered with an enlarged wing. This wing was the most important difference between the F.VIIa-3m and the F.VIIb-3m.

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Confusion in types.
When in 1925 the F.VIIa was converted to the F.VIIa-3m for the Ford Reliability Tour, the wing remained basically the same except of course for the provisions for the additional engines. It was clear to the designer however that the fuselages of both the F.VIIa and F.VIIa-3m could carry far more load provided certain changes were made. Important among these were more powerful engines - which were already under development - and an increased wing area. The solution to this last requirement was simple. The portion of the wing that was situated above the fuselage was of constant chord (i.e. a constant distance between leading and trailing edges), while the remainder of the wing tapered towards the tips.

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By extending this constant chord section by 7 ft 10.5 in, the span was increased to 71 ft 2 in, and wing area from 630 ft2 to 728 ft2. While this made the wing larger, it did not make it stronger: this was done later. The designation F.VIIb-3m was first used in 1928. Prior to that it was F.VII-3m for both the 'a' and 'b' versions. This temporary identification has been a source of confusion ever since, not only in publications but even in the type designations as painted on the fuselages, e.g. F.VII3m, F.VII3M, F.VIIa3m, F.VIIb3m, F.VIIb-3m etc.

Busy years.
Production of the type at the Fokker works in Amsterdam ended in 1932. Complete production records no longer exist, but it is known that at least 63 were built there. KLM had 14 and used them for many years on just about all the airline's routes. KLM considered the type a success both technically and financially with operating costs per seat mile only a quarter of those of the F.III. KNILM, the initials under which KLM operated in the Netherlands East Indies, had six. In the course of many years of service, KLM and KNILM's aircraft rarely hit the headlines. Adventure was out: airline flying had become a daily routine.

No F.VIIb-3m's survived the Second World War except one, the very first and by far the most famous - the Southern Cross.

Click on the picture to enlarge