In the late twenties and early thirties, the three-engine aircraft scheme was quite popular among aircraft designers around the world. It was used for both military and civilian vehicles. Many famous aircraft of that era had this layout - the Dutch Fokker F.VII / 3m, the German Junkers Ju52 / 3m, our ANT-9 and many others. Three engines provided the aircraft with a good thrust-to-weight ratio and increased reliability, which was important for long-distance flights. However, following the increase in power and reliability aviation By the end of the thirties, three-engine engines practically disappeared from the air forces of most countries, and even few of them remained among civilian vehicles. And only in the Italian Air Force until the very end of World War II, three-engine bombers remained in combat formation. The most massive of these was the SIAI S.79 bomber (better known as the Savoy-Marchetti). In total, almost one and a half thousand of these machines were produced, which exceeds the number of other Italian multi-engine bombers of that time combined. This is perhaps the best proof that the S.79 was rightfully considered the main combat unit of the Italian Air Force "Reggia Aeronautica".
As you know, many bombers in the 1930-x were built at first as a passenger car. The seventy-nine was no exception. SIAI Chief Designer A. Marchetti began the development of an eight-speed airliner in the 1933 year. The new aircraft was created to participate in the international air race London-Melbourne, where the Italians were hoping to win.
The S.79 design repeated the technology of the previous machines of the company, having a wooden wing and a truss fuselage made of chrome-molybdenum pipes, which were sheathed with plywood and canvas. The main innovation of the project was the retractable landing gear. The main pillars were hydraulically pressed into the wing nacelles, and the small tail wheel was closed with a fairing.
Created specifically for the flight London - Melbourne, the first copy of the S.79 nevertheless was not made by the beginning of the race. He made his first flight in October 1934 of the year. The passenger plane (the eight-seater cabin had wide rectangular windows) was raised into the air from the Cameri airfield by pilot A. Bakula. On the first prototype, there were three air-cooled motors “Piagio” P. IX C.40 “Stella”. Nine cylinder "stars" developed on takeoff 660 hp and three-bladed screws with two fixed blade pitch positions were rotated.
Having good aerodynamics, the liner also had excellent speed characteristics. With the take-off mass in 9200 kg, the S.79 reached speeds in 410 km / h - more than the serial Italian biplane fighters of those years. For the first time such a high figure was reached in June 1935, when S.79 performed a certification flight from Milan to Rome.
Test pilots noted the good behavior of S.79 in the air, and only the engines caused complaints because of unreliable performance. In addition, crimped hoods do not provide effective cooling of the cylinders. Already in July, the 1935 th at the first S.79 installed the Alfa-Romeo 125RC35 air cooling motors, with an 680l.s takeoff power, which were equipped with new NACA type hoods. Due to the replacement of engines, the take-off weight increased to 10580 kg, but the speed of the aircraft not only did not fall, but even increased to 430 km / h. General D. Valli, who held the post of Chief of Staff of the Italian Air Force, was personally convinced of the “fighter” habits of the aircraft at the end of the summer.
The crew, composed of Major A. Bizeo and Captain D. Castellano, was to deliver a high-ranking military officer to inspect the military units in Eritrea, where preparations were under way for the invasion of Italian troops into Ethiopia. After taking off on 1 in August in Rome, S.79 flew to Eritrea through Cairo, and on August 5 set off on its way back. Net flight time in transit was 11 h. 45 min. at an average speed of 365 km / h. In the flight, Valli himself took several places at the helm several times, never ceasing to admire the plane. In the future, such a pleasant acquaintance of the Chief of Staff of the Air Force with S.79 played an important role in the fate of the winged car.
At the beginning of autumn, the same crew on S.79 set a number of new international records. 23 September 1935 of the year, rising from the airport of Urbe near Rome, the plane flew over Italy on a closed route. As a result, the S.79 became the FAI record holder at distances in 1000 km and 2000 km with a payload in 500 kg, 1000 kg and 2000 kg, showing, respectively, the average speed of 390,97 km / h and 380,95 km / h.
Records improved again next year, when the first S.79 received the more powerful Alfa Romeo aviation engines 126RC34 for 780 hp. Now the average speed on closed routes in 1000 km and 2000 km was respectively 420 km / h and 390 km / h.
Naturally, a passenger plane with similar speed characteristics could not help but interest the military. The designers of SIAI understood this perfectly well, starting work on the bomber version of the S.79 almost immediately after the departure of the first prototype. Already in September 1935, Adriano Bakula lifted into the air the second three-engine S.79, already created as a bomber.
The Italian Air Force, in need of updating its fleet, in 1934, a competition was announced for a new medium bomber. But according to its conditions the plane was supposed to be twin-engine. The logic of the military is easy to understand - with such an arrangement, it is convenient to place the navigator-scorer in the bow, with an eye and a machine gun to protect the front hemisphere. To fit into these requirements, SIAI proposed the S.79 with a pair of air-cooled Gnome-Ron, Mistral Major, or Hispano Suiza H5.79 (liquid-cooled) engines. However, the Air Force abandoned this project because of the unsuccessful deployment of bomber and small arms.
Disagreed with the opinion of the commission only General D. Valli. He did not cease to praise the three-engine S.79 for speed, considering this quality as the main one for the combat vehicle. In addition, the simple design of the aircraft from the truss frame and plywood trim allowed to quickly launch the production of much-needed aircraft. And despite the official refusal of the military from any version of the "seventy-ninth," Valli personally ordered the construction of a small series of 24-x S.79 three-engined bomber for the Air Force.
Improvements made on the bomber of this small party, primarily related to the installation of weapons. Marchetti believed that the high speed of the S.79 would allow him to avoid frontal attacks of fighters. Therefore, the mobile machine gun for firing ahead was abandoned, leaving only a fixed "Breda-SAFAT" caliber 12,7 mm in the "humped" superstructure above the cockpit and the commander of the crew himself fired from it. In the back of the "hump", the radio operator, if necessary, occupied the defense, operating the same machine gun, but on a mobile unit.
The crew included a flight mechanic and second pilot-scorer, and they also had one machine gun. The mechanic with the beginning of the air battle took place in the tail, having the opportunity to throw his machine gun from one side to another, firing through rectangular windows.
The most unusual workplace went to the scorer. When the plane went into bombing, the co-pilot moved to the gondola under the fuselage, because the nose was occupied by a motor. From here, the pilot-scorer led and guided, using the bomb-sight and the backup steering wheel steering wheel. The gondola had windows at the bottom and on the sides, and in the back for firing down the rifle caliber Lewis machine gun was installed in it.
The crew climbed into the bomber through the oval door (reclined down like a ladder) on the port side behind the wing. In order not to interfere with the passage into the cabin, the bomb bay shifted slightly to the right. Bombs of various calibers - 2x500 kg, 5x250 kg or 12x100 kg could be hung vertically in it.
The first prototype of the bomber was obtained by the Alfa Romeo 125RC35 engines with the take-off power of the 680 hp. Fuel tanks in the wing and engine nacelles contained 3320 liters of gasoline. Solid wood three-spar wing with plywood trim had two-section flaps and automatic slats.
An experienced bomber was sent for comprehensive verification to the test center in Gvidonii. SIAI management has not stopped praising the record S.79, calling it the fastest bomber in the world. And although this was not true, the military pilots primarily noted precisely high speed. The command of the Air Force could not but rejoice and its range. With a full load, the S.79 could fly at cruising speed in 340 km / h distance in 1900 km.
The insistence of the Chief of Staff of the Air Force was not in vain: the tests proved that the three-engined bomber turned out to be quite successful and could be put into service. Although the Italian Air Force continued to consider the twin-engine vehicles as the main medium bombers, four regiments decided to equip them with three-engine Savoys (the total number of S.79 in them was 96 aircraft).
By January 1937, all 24 S.79 of the first order had been rolled out of the workshops of the Sesto Calende plant. Machines almost did not differ from the prototype bomber and equipped with the same engines. The following three-engine Savoys have already received more powerful Alfa-Romeo 126RC34 engines for 780 hp. The order for the S.79 increased over time as problems arose with the operation of the Caproni Ca.135 and Piaggio P732 twin-engined bomber.
In connection with this situation, the leadership of the Air Force had to change its point of view on three-engined bombers, and it was S.79 that gradually became the main medium bomber.
For the first batch, SIAI received an order for the next 24 aircraft, and soon another for 82. The S.79 assembly was licensed at the Aeronautics McKee Company, where the first contract was signed for the supply of 24 bombers.
The first combat unit, which received the "three-engine", was the 12-th bomber regiment. The regiment was based in Guidonia, and the first S.79 were overtaken here from the Sesto Calende plant in October 1936 of the year. "Seventy-ninth" at that time was considered a very high-speed combat vehicle, and fighter pilots were specially sent to the regiment, believing that they would retrain for such a modern aircraft much easier.
The pilots just started to get used to their vehicles, as they received real combat missions. In the outbreak of the Spanish Civil War, Franco and Italy immediately came to the aid of Franco. The military conflict on the Iberian Peninsula was ideally suited to test the latest weapons, and as early as February 1937 three S.79 from the 12 regiment landed at the San Juan airfield (Majorca island). Hence the Savoy and made their first combat sorties, attacking Republican ships, the Reus airbase and military depots in Cartagena.
By the summer, another two dozen S.79 had arrived in Mallorca, and part of the bombers of the 12 regiment had flown to Soria in northern Spain. From this base of "Savoy" on April 28, 1937-th headed towards Guernica, making a terrible contribution to the destruction of the defenseless city.
The number of S.79 in Spain increased every month. By the end of 1937, another 54 aircraft arrived. Among them was part of the ordered S.79 for the rebels. Spanish Fascists bought the Savoy 26 in Italy, the first of which appeared in San Juan in April of the 1937. In August, L. Pardo took command of the 3-G-28 group of eight S.79. The crews of the unit flew before this also on the three-engine aircraft Ju.52 / Зт. In September and November, 3-G-28 was joined by another two groups of nine bombers each.
In the spring of next year, the Franco received an additional eight S.79, which became part of the newly formed group 0-0-28. Continued to fight and the Italian crews. In May, the 1937 of the five Italian S.79 attacked the battleship Haile I in the bay of Almeria, but only one bomb hit the ship. In July, the 12 triple-movers bombed out on the fortifications of the Republicans near Bilbao. In addition, Mallorca was regularly raided against Barcelona, Valencia, Alihanta and Cartagena.
The beginning of the military career in Spain for the "seventy-nine" was very successful. Bombers flew without cover and left in case of danger from enemy aircraft. It was possible to catch up with the S.79, perhaps, only with AND-16, but there were not many of them in Spain, and the main Republican fighter fleet were less high-speed biplanes. And if the Savoy appeared over the target at night, then the chances of knocking down the three-engine were reduced even more.
Italian crews switched to night sorties at the end of 1937, and among the pilots there were even high ranks of the Italian Air Force. For example, on January 1 on 1938, the Chief of Staff of the Air Force, General Wally, flew to the bombardment of Barcelona. Moreover, the general took off from the Guidonia airfield near Rome and reached Spain in the dark. Dropping 800 kg of bombs over Barcelona, Valley calmly returned, flying around 2000 km. The night raids on this city were continued in March by the crews of the 8 regiment, but their route was shorter - S.79 took off from Mallorca.
By the spring of 1938, 170 S.79 bombers were assembled at three Italian factories (since the spring of 1937, Reggiani was connected to the production), of which 78 was in Spain (44 belonged to the Italian Air Force and 34 belonged to Franco's aircraft).
At the end of 1938 and at the beginning of 1939, the next two shipments of the Italian Savoy - 12 and 10 aircraft arrived at Mallorca. Thus, the total number of S. 79 warring in Spain was exactly a hundred. By that time, besides the digital index, the “triple-mover” also received its own name - “Hawk”. But the crews called their aircraft for the characteristic protrusion behind the cockpit more eloquently - "Hunchback". The offensive nickname had no effect on the successful use of S.79 in the civil war. And although for the entire time of the fighting in Spain the losses of the "seventy-ninths" amounted to 39 aircraft, only the 4 bomber was shot down in the air, and the rest of the Republicans destroyed on the ground during raids on the airfield.
With the end of the war in the Iberian Peninsula, the Italians did not begin to return their S.79 home, but left them to the Francois. Some of these aircraft calmly survived the Second World War, remaining in flying condition until the mid-fifties.
To be continued ...
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