Flight, August 1923
GOTHENBURG International Aero Exhibition 1923
Nordflug Werke, Teltow, Berlin. - This firm exhibited a small school type monoplane flying boat. We remarked in a previous article that the finish of this machine was not very good, and have
since learned that this was due to a strike, which all but prevented the machine being finished at all. The Nordflug type F.B.I was designed by Herr Ing. E. B. Harder, and the hull form was chosen after extensive tests in the tank at the Preussischen Versuchsanstalt fur Wasserbau und Schiffbau, under the direction of Dr. Ing. K. Schaffran. There are two steps, but the hull is remarkable for having a concave bottom in front of the main step. This is unsual in two-stepped hulls, although used almost universally on the Italian one-stepped hulls.
The boat hull is built of three-ply wood, and altogether but a minimum of metal parts is used in the construction. The Nordflug F.B.I resembles somewhat the Dornier "Libelle," and it is worthy of note that lateral stability on the water is obtained in the same manner by "wing roots" growing out of the sides of the boat.
The monoplane wing is in three sections, of which the centre section is an integral part of, and remains in place on, the rest of the structure. This section is braced by steel tubes, but the end sections are cantilevers. The ailerons are unusual in that they are not formed of the trailing edge, but of the extreme wing tips, as in the very early French Goupy machines. Whether or not this form will prove effective is a matter of speculation, although it is stated that on a previous type they were found to work very well.
The five-cylinder 60 h.p. Siemens engine is mounted above, and slightly ahead of, the leading edge of the wing, and the petrol tank is carried in the cowling behind the engine. The latter is neatly covered in, and faired into the centre-section. Seating accommodation is provided for two people in separate cockpits, one behind the other. Normally the pilot occupies the rear seat, and the pupil, or passenger, as the case may be, the front seat, which is on the centre of gravity of the machine, so that the presence or absence of a passenger does not alter the trim of the machine.
Following is a brief specification of the Nordflug Werke type F.B.I: Length, o.a., 6.8 m. (20 ft. 4 ins.); Span, 10-3 m. (33 ft. 9 ins.); weight empty, 310 kgs. (672 lbs.); useful load, 250 kgs. (550 lbs.), corresponding to pilot, passenger, fuel for three hours (110 lbs.), and 110 lbs. of luggage or freight; total loaded weight, 560 kgs. (1,222 lbs.); speed, 140 kms. (87 m.p.h.); ceiling, 3,200 m. (10,500 ft.).