Flight, December 1921

THE FOKKER "F.IV”
A Dutch 1922 Model

   WHILE the Fokker "F.III" has, undoubtedly, done excellent work on the London-Amsterdam service during the past year, it is expected that, as people develop the air habit, the demand for a greater number of passengers will necessitate somewhat larger machines for next year's air lines. It is in order to meet these anticipated requirements that the Fokker "F.IV" has been designed.
   As will be seen from the accompanying illustrations, the "F.IV " resembles in general outline the "F.III," of which it is approximately a geometrical enlargement Minor detail alterations have been incorporated, but these are not apparent from the general views. The fuselage, which appears to be of extraordinary length, is of the same construction as that of the Fokker "F.III," i.e., a steel tube structure with struts and longerons joined by welding.
   The cabin is divided into two compartments, of which the front one is considerably larger than the aft one. In the larger cabin is seating accommodation for six passengers, three on a sort of sofa running right across the cabin, facing forward, and three separate chairs near the front of the cabin, facing aft. The aft cabin has a single sofa seat for three passengers. Aft of the rear cabin is a luggage compartment which has its own separate door, so that the luggage does not have to be handed through the cabin.
   The power plant, which may be a Rolls-Royce "Eagle," a Napier "Lion," or a "Liberty," is installed as in the "F.III," on a tubular framework in the nose of the machine, and the pilot sits behind and slightly to one side of it, his seat being so arranged in the "F.IV," that his head is in front of, and on a level with, the leading edge of the wing. He therefore obtains a much better view laterally than he did in the "F.III," where he was seated in a scoop in the leading edge.
   The wing construction is the same as that of the "F.III," i.e., there are box spars, with three-ply sides and spruce flanges, and the whole of the wing is covered with three-ply. The only innovation appears to be that the wing is divided into two halves, not longitudinally, as one might have expected, but laterally, the entire trailing edge being made as a detachable unit.
   With the exception of the features indicated, the Fokker "F.IV," is, as already stated, practically a scale enlargement of the "F.III," whose features have been described in detail in FLIGHT, and which are, therefore, well-known to our readers. Suffice it to add that a cruising speed of about 105 miles per hour is anticipated, which should considerably shorten the time taken by the "F.III's " in covering the distance between Amsterdam and London.