FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1933
1933 - 0706.PDF
FLIGHT, OCTOBER 5, 1933 ing speed is 154 m.p.h., the duration is less than 3 hr. The tankage is actually sufficient for approximately 1,000 miles, but in that case the pay load must, of course, be correspondingly reduced. The general layout of the Fokker F.XX is well shown in the scale drawings and photographs. In the main it follows the well-known Fokker formula, and it is not until one sees the machine in flight with the undercarriages re tracted into the wing engine nacelles that the new type obtrudes itself, although the rounded sides and bottom of the fuselage, as well as the N.A.C.A. engine cowlings, indicate careful cutting down of head resistance. If one examines the figures given in the table on the previous page, it is found that the power loading is 10 lb./h.p., and the wing loading 18.8 lb./sq. ft. With these loadings the maximum speed is very good at 186 m.p.h., giving a value of the Everling " High-speed Figure " of 23.53, which is exceptionally high for a three-engined aeroplane, and reflects the advantage of retracting the undercarriages. Wing camber flaps are fitted to the trailing edge between IN THE OFFICE : Below, the dual controls and instrument board. On the right, the wireless compartment. The large wheel operates the undercarriage retracting gear. THE CABIN, LOOKING AFT : There is comfortable seating accommodation for 12 passengers. the fuselage and ailerons, and result in a reduction of about 9 m.p.h. in the landing speed, giving a speed range of very nearly 3 to 1. The ratio of gross weight to tare weight is 1.654, so that the machine carries as disposable load 65 per cent, of its tare weight. This is a fairly com mon ratio, but indicates that the cantilever wing need not lead to an unduly heavy structure if a fairly high wing loading is employed. The engines are Wright " Cyclones " of 640 b.h.p. each, at 1,900 r.p.m., and when the machine is fitted up for 12 passengers, and carries a crew of three, and fuel and oil for 400 miles, the actual pay load is 4,235 lb., or 2.2 lb./h.p., based on maximum power. The machine cruises on 1,280 b.h.p., however, and the pay load per cruising h.p. is therefore 3.3 lb. In view of the high cruising speed this cannot be considered an excessive power expenditure. As already mentioned, the Fokker F.XX is structurally similar to other Fokker machines, with a welded steel tube fuselage and an all-wood wing. The fuselage is covered with fabric, except immediately behind the engines, where the covering is electron sheet. The wing covering is ply wood. The Wright " Cyclone " engines are installed in the orthodox fashion, but the petrol tanks, which in previous Fokker machines have been placed above the cabin, are housed in the wing on each side of the fuselage, as the central part of the wing forms part of the cabin. The tanks are of welded aluminium, and each of the four has a capacity of 143 gallons, giving a total petrol capacity, when the tanks are completely filled, of 572 gallons, which is sufficient for a flight of about 1,000 miles. Although the petrol tanks are situated above the engines, direct gravity feed is not employed, the fuel being conveyed to the carburetters by engine-driven pumps. There is a hand pump for emergency, and also for use when starting up. The pilot's cockpit is totally enclosed, but the side windows, which are large enough to serve as emergency exits, are of the sliding type. The seats for the two pilots are placed side by side, and are adjustable for angle of tilt as well as for position. The first pilot sits on the left, and has to the left of him the wheel for setting the camber gear flaps. Between the seats is a knob by means of which all electric leads are rendered " dead " in order to
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
