 In an unusual decision, Fokker engineers went to great length in soundproofing the passenger cabin, enabling passenger to converse in a normal voice after take off.It was delivered to KLM and operated on European routes from March 1935.Although it had a good payload its range was much less than and was structurally inferior to (the maintenance advantages of all-metal aircraft were becoming clear) the new Douglas DC-2 and DC-3 and only one was built.