Flight, May 1935

ITALY'S LATEST TRANSPORT
The Fiat G.18 An Eighteen-Passenger Monoplane with a 185 m.p.h. Cruising Speed

   ULTRA-MODERN in conception, the new Fiat G.18 monoplane is an excellent example of the highly creditable commercial machines being constructed in Italy to-day.
   As regards constructional features, the wings are completely of duralumin, with three longitudinal members and, for the most part, smooth sheet duralumin covering, although the trailing edges are fabric-covered. The tips are easily detachable from the main wings. It appears that the ailerons are connected to the gear controlling the trailing-edge flaps, so that when these latter are lowered the ailerons behave in a similar manner, although retaining their differential movement. The wing is tapered both in plan form and in thickness; the centre portion is built up of steel tubing, and carries the engine mountings, retractable undercarriage and petrol tanks.
   Duralumin is employed for the entire fuselage, and the skeletons of the tail members are also of this material. Except for the tail plane, which is covered with smooth metal sheet, the tail units are fabric covered. Retraction of the landing wheels is effected by an electric motor, although an emergency hand gear is provided for safety's sake. Each half of the landing gear is fitted with a fork, consisting of two compression legs, and has a compressed air brake and a medium high-pressure tyre.

The Engines

   Power is provided by two Fiat A.59R. geared and supercharged radials giving 700 h.p. each at 2,150 r.p.m. at 6.500ft. These are actually Pratt and Whitney "Hornets" built under licence, and are fitted with N.A.C.A. cowlings, the forward portions of which are readily removable by unscrewing four bolts. The engine nacelles have fireproof bulkheads and a special type of oil cooler fitted with shutters controlled by the pilot. Hamilton three-bladed variable-pitch airscrews, and hand and electric starters are fitted as standard.
   The rods and cables leading to the control surfaces pass beneath the cabin floor in easily accessible conduits. All cables are duplicated, and each movable surface has a trimming "tab."
   Although the G.18 has a maximum speed of 210 m.p.h., its cabin is by no means cramped. It is 6ft. high, 5ft. wide, and 29ft. 3in. long. There are eighteen seats arranged in two rows of nine, with a central gangway; the distance from the back of one seat to that of the next is 36m. Each passenger has a window of safety glass, an electric lamp and an adjustable ventilator.
   Individual ventilation is secured by admitting into the cabin air which enters a vent in the nose of the fuselage, and distributing it through piping to each passenger. Heating is effected by conducting through various openings near the floor a mixture of cold and hot air which is graduated to maintain the desired temperature.
   Wireless and an exceptionally complete array of navigational instruments are carried in the pilot's cabin, which is situated well forward and allows an excellent outlook.
   The main data on the Fiat G.18 are as follows:-
   Wing area, 947 sq. ft. (88 m2); weight empty, 11,794 lb. (5 350 Kg.); gross weight, 17,637 lb. (8 000 Kg.); maximum speed, 210 m.p.h. (340 Km/hr); cruising speed, 185 m.p.h. (300 Km/hr); ceiling, 21,000 ft. (6 500 m); ceiling on one engine 8.800 ft (2 700 m.); range, 500 miles (800 Km).

Flight, June 1938

VENETIAN VENTURE
Avio Linee Inaugurates London-Venice Service with Fiat G.18-V

   THE assortment of transport aircraft using Croydon has lately been supplemented by the business-like low-wing Fiat G.18, used by Avio Linee Italiane S.A. for its new London-Venice route. The first official flight was made from this country last Wednesday, though a year ago the Paris-Venice connection was introduced with encouraging results. Scheduled times are: Depart Croydon 8.45 a.m., arrive Paris 10 a.m.; depart Paris 10.30 a.m., arrive Turin 1.15 p.m. ; depart Turin 1.45 p.m., arrive Milan 2.20 p.m.; depart Milan 2.30 p.m., arrive Venice 3.35 p.m. The initial trip enabled us to get in a leisurely sun bathe and swim from the Excelsior Hotel on the Lido, having left Croydon at the gentlemanly hour of 8.45 a.m.
   The Alps are cleared at about 15,500ft., the built-in oxygen system proving a very definite boon. Delivery is through individual leads and regulators from a set of cylinders in the extreme nose of the fuselage. Carefully studied heating and soundproofing (the latter by Dr. Zand, of Sperrys) keep things happy.
   The pilots give the G.18-V very high marks, enthusing particularly over its behaviour under ice-forming conditions. The machine is virtually the "speed model" of the G.18, also employed by Avio Linee. The company has six G.18-Vs and four G.18s with Fiat-built Hornets. One of the latter, incidentally, took over at Milan.
   The essential difference between the two models is that the "V" type is powered with two fully super­charged Fiat A.80 R.C. eighteen-cylinder radials giving 1,000 h.p. each at 13,500ft. This is the first “eighteen” to go into production; the weight is 1,600 lb. They are geared 5:8, and drive Fiat-Hamilton c.s. airscrews. The cowlings are of the long-chord Magni variety and starting is effected by a Garelli compressed-air system. No fuselage fuel tanks are fitted (there are eight in the wings, sufficing for a range of 1,025 miles) but smoking is not permitted.
   Three-spar wing construction is employed, the wing covering being both smooth metal and fabric. Chrome molybdenum steel tubing is used for the centre section.
   The fuselage is flat-bottomed and slab-sided and is divided into a compartment for two pilots and a wireless operator; the passenger cabin (normally with eighteen seats); the toilet, and a luggage compartment extending almost to the tail. We sounded Signor Gabrielli, the designer, on the design of the fuselage; he referred to N.A.C.A. recommendations relating to the high aero­dynamic efficiency and said that the particular shape adopted shows up well in obviating tail buffeting.
   Signor Gabrielli, by the way, is very well known among the technical fraternity in this country and is responsible for the design of the Fiat G.50 monoplane fighter now in large-scale production for the Regia Aeronautica. He is firmly of the belief that high wings for transports are highly over-rated, because after the initial thrill of flying a passenger usually goes to sleep or produces a book. Commercial considerations permitting, he would like to design a mid-wing transport.
   To return to the trip: the Turin-Milan section offers a grand view of the flat plain of Northern Italy. The fields are apparently cultivated to the limit and have been flooded to compensate for a drought. The Fiat cuts across the southern end of the magnificent Lake Garda, where the Italians have conducted the bulk of their research with high-speed seaplanes. Approaching Venice the vista of the seascape set one musing as to what interpretation of the scene Turner would have given. The San Nicolo aerodrome is small and narrow and our approach caused us to cut low across the bows of a cargo steamer. We were somewhat amazed (it being our first visit) at the bulk of shipping, but even more so at the variety of large trans­port machines on the aerodrome. We spotted among others a Ju. 52, an Electra, a Savoia S.73 and one of the handsome new Savoia S.75S.
   On the return trip we were joined some way inland by a pair of Fiat C.R.32 fighters which, we gathered from our second pilot, were from Ghedi aerodrome. They became embarrassingly playful and it was probably as well that most of our fellow passengers were dozing.
   The Alpine crossing was made under the most perfect conditions. Our radio operator beckoned us up front into the sanctum of our sociable pilots, Lotti and Guido, so that we might derive the utmost pleasure. We had barely settled back in our seats when our wings began to rock quite sharply. Looking ahead we saw the reason; we were greeting a grey sister ship which we passed at a relative speed of nearly 400 m.p.h.
   We had about 45 minutes for lunch at Le Bourget, where there is usually something worth looking at. On the out­ward run it was the King’s Envoy, doubtless on business relative to the impending visit of Their Majesties; this time it was a camouflaged L.A.P.E. Douglas from Spain.
   One finished the trip with the conviction that Avio Linee is an up-and-coming line. Plans for expansion include the ordering of seven Fiats with four eighteen-cylinder radials of about 1,300 h.p. each. Some of these are likely to be put on the Abysinnian route and others may be used for the lucrative Turin-Rome service.
   The present, fleet of the company is: Six Fiat G.18-Vs; four Fiat G.18s; six Savoia Marchetti S.M.73s; one Douglas D.C.2; and one Fiat A.P.R.2.