As an ensign in the Navy, Leroy Randle Grumman had worked with Albert and Grover Loening on a Navy monoplane contract. Upon resigning his naval commission in 1920, Grumman joined the Loenings as test pilot for their Air Yacht amphibians, and over the next several years, he took over full responsibility for the company’s aircraft design.
The Loenings sold out their company in 1929 and backed Grumman in a venture of his own incorporated in 1929 at Farmingdale, New York. With their investment of $30,000 making up almost half of the initial capital, Grumman and five other engineers opened the Grumman Aircraft Engineering Corporation in an abandoned garage in Baldwin, Long Island.
Contractor to U.S. Navy and Coast Guard. Built FF-1 (first flown 1931) and SF-1 two-seat biplane fighters with retractable landing gear, followed by single-seat F2F (first flown October 1933) and F3F (delivered 1936), plus all-metal amphibian as the JF-1 (first flown May 1933), later known as the Duck.
In 1936 Grumman moved to Bethpage, Long Island, NY.
Subsequent production, mainly for the U.S. Navy and Marine Corps, included F4F Wildcat fighter (first Grumman monoplane, first flown September 1937), TBM Avenger torpedo-bomber (first flown August 1941), F6F Hellcat fighter (delivered from 1943), F7F Tigercat twin-engined carrier fighter-bomber (first flown December 1943) and F8F Bearcat fighter (first flown August 1944) during Second World War, plus Widgeon and Goose (delivered from 1939) amphibians.
By 1943 his staff had grown from six to 25,000 employees.
Postwar aircraft included the antisubmarine Guardian (first flown December 1945), Albatross amphibian (first flown October 1947), F9F Panther as its first jet fighter (first flown November 1947), and F11F Tiger day jet fighter (first flown July 1954 in original F9F-9 form).
Grumman’s entry into specialized electronic warfare aircraft began in December 1952 with the first flight of its S2F Tracker (later S-2), though this was a carrierborne antisubmarine aircraft. From Tracker were developed variants for carrier transport operations; the C-1 Trader and, more importantly, the WF (later E-1) for airborne early-warning, with an over-fuselage radome (first flown March 1957) and based on the S-2A. Such was the success of the E-1 concept that the much improved E-2 Hawkeye was developed, which first flew in October 1960 (originally as W2F-1) and remains in production in 1999 by Northrop Grumman, itself leading to the C-2 Greyhound transport derivative (first flown November 1964). Grumman also developed the OV-1 Mohawk for the U.S. Army for observation, first flown April 1959 and also using the successful twin-turboprop engine layout.
In April 1960 Grumman flew the A2F-1, which in production form became the A-6 Intruder twin-jet carrier borne long-range and low-level strike aircraft, finally withdrawn from service in the late 1990s. Intruder itself spawned an electronic warfare variant, the EA-6 Prowler, first flown May 1968 and still in service in 1999. The final fighter to carry the Grumman name was the F-14 Tomcat, designed as a carrier based variable-geometry long-range type armed with super-long-range Phoenix air-to-air missiles (first flown December 1970, entering service with the U.S. Navy from 1972 and exported to Iran for land-based operations from 1976).
Grumman merged with American Aviation to form Grumman American.
By the time Tomcat had flown company had been divided (1969) into Grumman Aerospace and other individual corporations via the Grumman Corporation holding company. American Aviation Corporation became part of Grumman American Aviation Corporation in 1973. In May 1994 Grumman and Northrop merged to form Northrop Grumman.
World War 1
Grigorovich S-1 / S-2 / Shchetinin S-1 / S-2
Between 1915 and 1916 at the Shchetinin Factory and based on a Grigorovich project, two “land” models were designed (in Russian Sujoputnie and hence the S in the name as opposed to the M for Morskoi or naval). The objetive of these models was to increase the performance of the Farman biplanes that the factory built under license.
The first of these projects, known as S-1 (Григоровича С-1), was designed as a conventional biplane heavily influenced by Farman’s designs and equipped with a rotary engine. Construction was abandoned before the prototype was finished.
A second model, called S-2, was designed as a two-seater aerial observation and reconnaissance aircraft and generally repeated the successful scheme of the Farman biplanes with a central nacelle and a rotary engine. As a “novelty” it is worth noting the use of double tail cones that ended in individual empennages joined by the stabilizer with the elevators.
The selected powerplant was the 100 hp French Gnôme Monosoupape.
The entire construction was made of wood, covered with fabric. The wings had an Eifel-36 profile and were characterized by a large difference in span between both planes and the use of parallel uprights with cable tensioners.
The S-2 was built and its assembly was completed in January 1916. During flight tests, conducted by pilot Ya. I. Siedov, an accident occurred and the plane was not restored as it was considered that there was no point in trying to improve the outdated Farman designs
Grigorovich MK-1 Sea Cruiser / Schetinin MK-1 Sea Cruiser
As early as 1915, a group of naval pilots had asked the Fleet for a long-range aircraft capable of carrying out long patrols, covering the entire Baltic Sea area. The start of the war increased the requests and increased when the conflicts with Turkey began.
On August 12, 1915, a meeting of the Aviation Committee of the Baltic Sea Liaison Service took place, in which once again the issue of the need for the provision of large seaplanes with a 6-hour patrol capacity was discussed. Based on these requirements, the builder DP Grigorovich proposed to build such a device.
The Marine Cruiser (Mosrkoi Kreiser or MK (Russian: Григорович МК-1 “Морской крейсер”)) was designed in 1916 to meet the requirements of the Naval General Staff (MGSh) and was conceived to serve with the Baltic and Black Sea fleets in long-range reconnaissance and bomber functions.
The MK-1 was the largest Russian seaplane ever designed and it only yielded to the Ilya Muromets bomber with floats.
The MK-1 featured a center float, biplane configuration, three engines, and a four-crew capacity. From the technological and constructive point of view, the model maintained the characteristics of the designs developed in the Schetinin Factory.
A feature was that the float and fuselage were merged into a single structure, resulting in a general outline of combined features. This float had such dimensions that it could generally be considered a hull. In its lower region it presented a redentient with concave and lateral sides similar to those used in Grigorovich’s M flying boats. The construction of the internal structure of the float was made of ash with plywood covering.
In the forward region of the fuselage the closed cockpit was located, built with plywood and with good frontal glazing. At the rear, the fuselage appeared as a wooden frame braced by cables and covered with fabric.
The wing box was of the conventional type with three pairs of struts in each half plane and a certain offset. The upper plane was slightly larger than the lower plane and had trapezoidal-shaped ailerons. The wing structure was conventional, with two wooden spars and a rather slim profile. It should be noted that this wing box was fixed to the upper part of the float body by means of rubber shock absorbers with a travel of 180 mm.
In the tail section there was a wide triangular keel on which the horizontal planes were fixed, braced by uprights and the large-area rudder.
Originally it was thought to equip the MK-1 with only two 220 hp Renault engines located between the planes. Later, when construction began, the designers realized that the weight of the model exceeded that calculated and the center of gravity was located a little behind, so it was decided to locate on the upper plane and on the line of the longitudinal axis a third engine. A 150 hp Sunbeam motor was first tested, but was later replaced by a 140 hp Hispano-Suiza V-cylinder motor, which was found at the factory. In this way the MK-1 became the world’s first three-engined seaplane.
The cockpit of the pilots in the MK-1 was characterized by being very spacious and located high above the hull. In the bow section a gunner was located operating a 76 mm gun.
The MK-1 was completed in the middle of 1917 and only late in the fall was it ready for testing. In November the pilot Ya. I. Siedov-Sierov attempted to make the first flight in Petrograd Bay, taking several people on board. The weather was not the most propitious, the cold wind had created waves. At the beginning of the take-off and giving full throttle to the upper engine, the nose sank and the water swept over the bow, filling a large part of the first watertight compartment of the hull. The “Cruise” was stuck on its nose and ended up sinking. All the crew members were able to be evacuated.
The flying boat was pulled out of the water with significant damage. The cause of the problem was considered to lie in design problems of the bow section of the float, which needed to be lengthened. The need was also seen to eliminate the upper engine and increase the power of the two located between the wing planes. This meant a major job that was decided not to undertake, especially considering that the GASN torpedo bomber was already being built, which seemed much more perspective. Thus ended the development.
Grigorovich/Schetinin MK-1 Sea Cruiser
Power plant: 2 x 220-hp Renault & 1 x 140-hp Hispano-Suiza
Upper plane span: 30 m
Length: 16.50 m
Height: 4.50 m
Accommodation: 4
Grigorovich M-20 / Shchetinin M-20
After leaving SS Schetinin and creating his new experimental factory, DP Grigorovich managed to obtain a contract for the construction of 40 training flying boats with Le Rhône engines of 110 and 125 hp. In general, they were Grigorovich/Schetinin M-5 hydros with minor changes in their construction, which is why the contract originally called the airplanes M-5, but when production began they would begin to be delivered as M-20s (Russian: Григорович М-20), to differentiate them from the copies built at the Schetinin factory.
The M-20 was generally similar to the M-5 flying boat, itself a development of earlier models with better hull hydrodynamics and modifications to the tail section for greater efficiency.
From the constructive point of view, the M-20 presented a typical design. The structure was made of ash covered with 3 mm plywood on the edges and 5 – 6 mm on the bottom. 10 mm plywood was used in the recess area. The internal structure was made up of frames with diagonal reinforcement supports in certain areas. Joints in the hull skin were reinforced by plywood plates fixed with copper rivets from the inside. In the lower outer area of the hull, the joints were covered with 0.3 mm copper sheets and soldered together with tin. On the outside the wood coating was covered with varnish and on the inside with pitch.
The construction of the wings, the stabilizer and the keel of the vertical empennage was made of pine wood. The elevators and rudders were built from a light structure of thin-walled steel tubes (30×28 and 20×18 mm) with some wooden ribs and fabric covering. The M-20 simplified the number of guy wires between the supports and the upper flange.
The wing featured a double spar structure, built from I-profile pine pieces with holes to save weight. The wing ribs were made from 20 x 5 x 5 mm pieces of plywood, also lightened by perforations. Its wing profile was extremely thin (4% chord bristle). The interplane supports were made of wood and the cross tensors were made of 5-8 mm cables.
Behind the cabin, the hull became little more than a trapezoidal section stringer with the narrowest face upwards, on which the characteristic drift and rudder assembly was located. The horizontal plane of the tail was raised to distance it from the effect of the water by means of a pyramidal structure of steel tubes and tension cables.
As a power plant, the M-20 used Le Rhône engines of 110 and 125 hp, which were installed in a steel tube structure fixed to the central supports of the wing box. The main fuel tank was located in the hull, behind the cockpit.
Pilot and student were accommodated side by side in an open cabin, located immediately in front of the wings.
In the middle of 1917 the tests of the first copy equipped with a 125 hp engine were carried out and the results obtained resulted in the confirmation of the original production contract. On March 31, 1918, the Grigorovich factory was nationalized and destined for the production of agricultural aggregates, so the engineer went to Sevastopol and only in 1920 would he return to Moscow to renew his work as an aeronautical constructor.
The production of the model went 1917 to 1920, ending with close to 80 copies at the 1917 price of 16,000 rubles.
In October 1919 a special commission chaired by NN Polikarpov studied the possibility of transferring the production of the M-20 flying boats to the Tverskoi Wagon Factory and later to the Duks factory in Moscow. The lack of experience in shipbuilding did not allow to develop this idea
Most of the M-20 units participated in the Civil War on the side of the reds. These flying boats flew in the Baltic, Caspian Sea, Volga, Dnieper and North Dvina rivers. As armament some copies carried a machine gun located on a tripod in front of the cabin on the right and bombs of up to 32 kg. Some survived until the mid-1920s.
М-20
Powerplant: One 120 hp Le Rhône
Upper plane wingspan: 13.62 m
Wing area: 37.96 m²
Length: 8.22m
Empty weight: 660kg
Flying weight: 960kg
Fuel and oil weight: 124 kg
Maximum load capacity: 300kg
Wing loading: 25.3 kg/m²
Power Load: 7.1kg/hp
Speed at sea level: 115km/h
Ceiling: 3500m
Time to 1000m: 9min
Time to 2000m: 22min
Endurance: 4 hr
Accommodation: 2
Grigorovich M-17
With the beginning of the First World War in Russia, the Army and the Fleet were forced to develop their own research and development units where the prototypes were designed, the production documentation was developed and the experimental units were manufactured, which would later be presented to the national industry in search of a candidate for production. With this objective, it was proposed to create in 1918 the Kherson centers for the Army and the Grebni port center for the Navy. Both institutions would be developed from state funds and rapid results were expected from them.
DP Grigorovich soon understood the situation and decided to offer his services to the Navy, proposing the creation of a specialized construction bureau and an experimental factory for the development of flying boats. The request for support from an experienced engineer was welcomed by the military and soon Grigorovich, who was already 33 years old at the time, was able to count on the necessary material resources to become independent and be able to carry out his ideas independently. SS Schetinin for his part, freed himself from the development. The Navy also gained from the real possibility of presenting real results in the short term and somehow demonstrating to the authorities that the decision to provide it with its own engineering facilities had not been simply another waste of money.
On June 1, 1917 Grigorovich ended his working relationship with SS Schetinin. Grigorovich received bank loans with low interest rates that allowed him to lease some facilities to organize an experimental factory and an empty building belonging to the Ismailovski regiment, at 12 Rota, Building 26. As an aid to be able to make the loan payment, the new facility received an order for the construction of 40 M-5 flying boats (later M-20), which was signed on July 28, 1917 with deliveries scheduled for the period between September 1, 1917 and January 1, 1918. The price of each unit was set at 16,000 rubles. In parallel Grigorovich received requests for the development of several experimental models.
Dmitri Pavlovich designed the flying boat that received the 17th consecutive in the series of naval models (Russian: Григорович М-17), obtained as a development of the M-11 fighter with a 130 hp Clerget engine. The second prototype, slightly modified, would receive the designation M-17bis.
For different objective reasons, the two M-17 copies would only be finished in 1918. The tests of the model began on September 26, 1918 and showed the same problems of the basic model M-11 among which the negative influence of the rotary engine and poor seaworthiness stood out. Despite not successfully testing as a fighter, both the M-17 and M-17bis entered service with the Baltic Sea Fleet, where they remained for some time.
According to VB Shavrov, the M-17 was equipped with the 150 hp Hispano-Suiza engine and several copies were built that served with the Baltic Fleet and between 1921 and 1922 even in the Black Sea. In November 1917 the M-17bis with a 130 hp Clerget engine would appear.
M-17
Power plant: Clerget, 130 hp
Wingspan: 8.80m
Length: 7.60m
Empty weight: 680kg
Normal takeoff weight: 940 kg
Top speed: 155km/h
Cruising speed: 135km/h
Accommodation: 1
Grigorovich M-16 / Shchetinin M-16
Pilot Nagurski’s flights in a Maurice Farman MF.11 model to the Arctic in 1914 showed that floats could serve not only to land on water, but also on ice and snow. With the M-11 Grigorovich had shown the possibility of installing skis on flying boats, but the performance was affected in such a way that the need soon arose to create a model capable of operating during the time when the waters froze in the north ocean seas.
Dmitri Grigorovich began work on the M-16 model between August and September 1916 (it could be a little earlier). Naval pilots needed a “winter” model, capable of operating on the frozen and snow-covered surfaces of the Baltic Sea.
With the war, the Navy was involved in multiple tasks, generally operational, so they could pay very little attention to channelling the interests. The Department of Aeronautics of the Naval General Staff (MGSh) could do little burdened with bureaucratic tasks. Under these conditions, the builders of the aeronautical factories began to define what type of naval aircraft to project, assuming that they would cover the needs of the military. The owners of these factories, on multiple occasions, worked on account and at risk. Military experience and engineering thought were divorced, but this procedure would constitute the seed for the development of an experimental aviation program.
On September 20, 1916 at a meeting attended by representatives of naval aviation, the aeronautical departments of the MGSh and GUK and representatives of factories (BP Dudorov, AA Tuchkov, IN Dmitriev, DP Grigorovich, Yu. A. Brezhniev and AN Tupolev) future requests for naval models were discussed. Those present defined the technical task for the projection of the winter model. This airplane had to have the ability to land on water, ice and snow with a landing speed of no more than 75 km/h. The maximum speed was to exceed 100 km/h.
Schetinin promised to have such a plane ready by mid-October. This model was the Grigorovich M-16 (Russian: Григорович М-16), although it is also known as Sch M-16 or Schetinin M-16, being one of the last works of Grigorovich before becoming independent to his own factory.
The M-16 was a single-engine biplane with a short crew gondola supported between the planes by a system of struts.
The wing, similar in construction to that of the M-9 model, was characterized by having a large area. The wing featured an unequal span and three sections supported and braced by tension cables.
Two flat-bottomed floats without grooves with a large support surface, necessary to operate on snow, were attached to the lower plane. Each float weighed about 77 kg, to which must be added a third very wide unit located under the tail region and weighing 8 kg.
The tail unit featured a single yoke and rudder assembly; Although similar in general configuration to that of the M-15 flying boat, the new aircraft’s rudder extended behind the horizontal planes, and the stabilizers were supported by four spars from the wings.
The central gondola, Farman type, accommodated the crew located in tandem, the instrumentation, the machine gun and the fuel. Aft of the gondola was a 150 hp Salmson liquid-cooled radial engine driving a two-blade propeller, with radiators located on the sides of the gondola.
Defensive armament consisted of a Lewis, Maxim, or Vickers machine gun located forward on a movable mount and operated by the spotter. The M-16 could carry up to 100 kg of small bombs.
On November 6, a naval commission participated in the factory tests of the M-15 and M-16 prototypes (with factory number 1080). The M-16 with a payload of 350 kg was capable of reaching 500 meters in 6.5 minutes, which was considered enough for a firm request for the construction of 40 examples to be made a couple of weeks later.
At the beginning of December, the first M-16 (it could be the prototype) was delivered to the Third Naval Station in Revel and received the registration ZS-1. On the 13th, piloted by Prokofiev-Severski, he managed to survive an accident about which the captain of the first rank BP Dudorov has left us evidence in a communication issued to the MGSh:
“Today during a race on the water after ditching, the M-16 winter aircraft broke the gondola stringers at the engine mounting site, which ended up falling off. Fortunately, everything ended without consequences. I request to stop all construction work on the “winter” apparatus and urgently send engineer Grigorovich to Revel to investigate the causes of this accident.”
Only two days later, Dudorov would recall his request again, since the situation had become extremely complicated due to the impossibility of flying the flying boats due to the winter frost.
On December 16 and with the presence of Grigorovich, the commission of naval aviators reviewed the plane and came to the conclusion that it would be necessary to raise the engine installation by lengthening the float supports and reinforcing the rear amortization system. of both units. It was also proposed to reinforce the entire engine installation system. For this, the rear supports had to be reinforced, adding new steel parts.
Everything seems to indicate that these recommendations were heeded and brought positive results, since in subsequent tests there were no problems with fixing the motors.
Another interesting detail is that on December 30 Military pilot Captain Grigorov, who at that time was studying at the Nikolayevsk Military-Aeronautical Academy, proposed to the Navy to test a self-designed fuel tank protection system on the M-16. Shortly before the war this officer had designed a protection system by coating the tanks with a layer of rubber that was considered cheap and effective and the M-16 greatly needed this system because the fuel tank was located in the nacelle, in front of the engine, so that in the event of a small fuel leak, the proximity to the hot engine could turn into a fire. It is not clear if this system was actually used on the plane, but there is evidence that protections of this type were prepared in the Russian-American Society “Triugolnik” based in Petrograd.
Based on the results of the first month of operation of the M-16, in January 1917 a list of requests for improvements in the construction of the model was delivered to the factory. In addition to the increase in the rear of the floats, the military requested to locate a transparent hatch in the floor of the gondola and the installation of steps that would allow the crew to occupy their positions, to locate a windshield in front of the pilot and to install on the left side a bombardment collimator designed by Senior Lieutenant SA Lishin. It was also requested to move the compass position and install an artificial horizon, as well as the installation of removable supports for bombs to be placed under the gondola and the wings.
The pilots highlighted a strange behaviour of the model from the elevators. When pulling the stick rearward, the plane initially did not react, but when the stick reached a certain position the plane “jumped” upwards. The same thing happened during the descent. It was pointed out that with a full tank and without a passenger, the model behaved quite well, but when the tank emptied a little or was carrying the weight of another person, there was a tendency for the plane to lower its nose, forcing the pilot to maintain constant pressure on the nose.
The initial production contract included a request for 40 complete examples, 10 without motors to be used as spare parts and an unspecified number of float sets. Production started from the end of 1916. In general, the Schetinin factory produced 36-40 examples.
Contract date: November 24, 1916
Number of copies: 40+10 spare without motor
Serial numbers: 1201-1232, 1242-1245
18,000 rubles per unit with a 150-hp Salmson engine and 17,700 for spare ones. 3150 rubles for each additional set of floats. Expected deliveries from December 10, 1916 to February 1, 1917.
Contract date: January 30, 1917
Number of copies: 1
Serial numbers: 1080
Contract for the purchase of the prototype
Between November 6, 1916 and July 1917 the Baltic Sea Fleet received at least 36 examples of the M-16. These planes were used primarily as scouts and patrol planes. The model became known to the military as ZS (Zimni s Salmsonom or Invernal con Salmson) and military registrations featured these letters and a consecutive number (ZS-1, ZS-2, etc).
At least one example was severely damaged during a fire on the night of January 6-7, 1917, and another was totally destroyed. The numbers of these were 1205 and 1206. By mid-1917, according to reports in the Baltic Sea Fleet, 15 were registered.
The Black Sea aviation did not need the “winter” models due to the climatic conditions in the area of operations.
Six M-16s fell into Finnish hands during the Russian Civil War. After the abandonment of Revel by the Russian troops, six M-16 in perfect condition went to Finland, where they were exploited for several years until being decommissioned around 1923.
The first Finnish parachute jump was done on June 17, 1922 from a M-16 by a parachuter named E. Erho. The aircraft were flown until 1923.
By May the Baltic winter campaign was over. The mechanics replaced the alcoholic coolant in the engines with a normal type and on the 22nd of that month, officer G. Ya, Erdeli received the order to prepare six M-16 units with wheels, but there is no evidence that this was done, nor does any evidence support VB Shavrov ‘s assertion that during winter operations some M-16s replaced their floats with skis.
In the summer of 1917 the head of the 6th Baltic Sea Air Division, Lieutenant AI Makarevich, modified one of the M-16s in order to improve its performance. The changes were made at the base of the division’s 2nd Brigade based at Abo and as a result the officer hoped to achieve a normal wheelset. Unfortunately this officer would never get to see his finished design. The winds of revolution reached Abo, discipline cracked and Makarevich’s authority degraded to such an extent that the Naval Aviation Command decided to reform the unit. The order came on July 18, but its execution was delayed and by the 30th the sailors, gathered between the hangars, assassinated Makarevich.
By mid-November, however, it was finished in the local workshops and prepared for testing. Apparently, the results were positive, since by the beginning of December at least three M-16 copies had been modified. Foreign intervention and the Civil War that followed erased practically all the evidence and for this reason no data on this project was preserved. Presumably without the heavy floats and their bracing structure the modified M-16 performed better.
With the arrival of the winter of 1917-1918 military activity in the Baltic area practically disappeared, the M-16 was used mainly in reconnaissance and liaison missions. For the summer campaign the model was totally obsolete, being able to be used only as a bomber.
Operators:
Estonian Air Force
Finnish Air Force
Imperial Russian Navy
Soviet Naval Aviation
Specifications:
M-16
Engine: 1 × Salmson, 150 hp
Wingspan: 18.0 m
Wing area: 61.8 sq.m
Length: 8.60 m
Empty weight: 1,100 kg
Max. takeoff weight: 1,450 kg
Full load capacity: 350kg
Fuel and oil capacity: 185 kg
Wing loading: 23.5 kg/ m²
Power Load: 9.7kg/hp
Maximum speed: 130 km/h
Speed at sea level: 110km/h
Cruising speed: 92km/h
Service ceiling: 3,500 m
Time to1000m: 15min
Time to2000m: 40min
Endurance: 4 hr
Crew: 2
Armament: 1x MG
Bombload: 100 kg
Grigorovich M-15 / Grigorovič M-15 / Shchetinin M-15
The M-15 type (Russian: Григорович М-15) was a development of the excellent M-9 and was characterized by the introduction of a new power plant with greater power with a certain reduction in the general dimensions, especially in the wing area. This model was built at the S. S. Schetinin PRTV facilities and is therefore alternatively known as the Schetinin M-15 or Sch M-15.
The M-15 was designed as a two-seater biplane flying boat with an unequal wingspan, made of wood and powered by a 150 hp Hispano-Suiza linear motor moving an “Integral” propeller with a diameter of 2.55 m.
In general, it repeated the construction characteristics of the M-9, but the wing box had only two sections and a reduced wing surface in both planes. The hull was of a completely new design and the remarkable engine was mounted on a complex system consisting of 10 bracing spars.
The M-15 crew consisted of a pilot and a gunner/mechanic. Both crew members were located in a common cabin, sitting side by side. The crewman on the right operated a Maxim or Lewis machine gun located in a position forward that was accessed by crawling from the cockpit.
The prototype with factory number 1079 was found ready for November 6, 1916 and that same day it was presented to the naval authorities. After a few short test flights in which the model reached a height of 500 m in just 4.5 minutes (with a load of 350 kg) it was accepted for service with the Fleet. Subsequently, it was decided to send the prototype to the Baku Naval Flight School, where test days were to be carried out under operating conditions in December.
In January 1917 requests for modification of the flying boat M-15 were received from Baku, but most were aimed at a more comfortable arrangement of instruments and improvements in control, as well as claims about the quality of finish.
One of the first requests to modify the model was received by PRTV on January 21, 1917, when the observation officer G. Ya. Erdeli urgently requested, on the instructions of his superiors, skis according to the drawings presented by the pilot Alexandr Prokofiev-Severski.
Soon a flying boat was modified in this configuration and on February 9, with its designer at the controls, it made a test flight. The pilot reported that the was trimmed, took off smoothly, reached a height of 1,000 m in 7 minutes, and landed on the ice without difficulty.
The consequent speed tests showed that the new undercarriage only slightly reduced performance and, however, significantly increased the model’s operating capabilities.
From the aeronautical point of view, the M-15 was positively valued. This model featured more speed and climb than the M-9. Its excellent response to controls was highlighted. During the process a firing point was installed in the bow of the model to install a Maxim or Lewis machine gun in two possible variants of nose configuration.
In operation, the M-15 was defined as an intermediate version between hunting and reconnaissance flying boats and in combat conditions it was superior to the M-9, so it was decided to approve its serial production.
The excellent results obtained during the tests of the M-15 motivated the request to build 80 copies in a first contract signed on November 24, 1916.
Contract date:
November 24, 1916
Number of copies:
80 + 20
Serial numbers:
1101-1153
18,000 rubles for each copy with a Hispano-Suiza engine of 150 hp and 17,500 rubles for spare copies without a motor. Delivery scheduled for April 15, 1917. Partially completed. Copies 1154-1163 were not delivered due to the absence of engines. The contract was modified on April 17 to 60 copies and 15 spare parts.
Contract date:
January 30, 1917
Number of copies:
1
Serial numbers:
1079
Contract for the purchase of the prototype.
Production of the M-15 began in the second half of 1916 and continued until the end of 1917. Unfortunately, the supply of Hispano engines was quite limited, so the M-15 failed to displace the M-9 in its flying boat role.
This problem with the supply of engines represented a severe blow to Russian aeronautical development, since most of the designs from the end of 1916 and the beginning of 1917 were based on Hispano-Suiza power plants with powers between 140 and 200 hp, who had been contracted in France and could not arrive on time.
The number of copies produced reached 54 units, including the prototype, of which almost more than half was used in the Baltic.
More than 30 units were delivered to the Baltic Fleet, about 20 units were redirected to the Black Sea and two units were delivered to the Baku flight school (prototype 1079 and 1144). The military designation of the model was SchI (Schetinin with Hispanic). Generally the model was used in reconnaissance missions.
The Red Air Fleet used several of these examples. From the summer of 1917 the units produced were used primarily as trainers.
Two copies of the M-15 went to Finland during the events of 1918, being framed in the local air force with the registration numbers C68/18 and C69/18. These specimens had been abandoned after the evacuation at the Åland and Turku bases, on the Baltic islands. In one of them, the Russian pilot J. Herbert would fly from Åland to the Finnish mainland and would be appointed an officer in the Finnish air force. This example remained in service in Finland until 1919.
The Germans captured some specimens that were displayed as war trophies. There is no evidence that they were ever used in service.
A perfectly preserved example is kept at the Polish Aviation Museum (Polish: Muzeum Lotnictwa Polskiego w Krakowie) located in Kraków, Poland. This flying boat, originally registered SchI-1, was damaged as a result of a bad landing on September 29, 1917, when the Russians left the Arensburg base on Ezel Island.
The Germans captured the flying boat and took it to Berlin as a war trophy. It was kept on static display in a Berlin Aviation Museum until 1945, when it was transferred to Poland.
М-15
Engine: Hispano-Suiza, 150 hp
Upper wingspan: 11.50 m
Wing area: 45.48 m²
Length: 8.43 m
Height: m 3.10
Empty weight: 840 kg
Flight weight: 1320 kg
Fuel and oil weight: 184 kg
Maximum load: 480 kg
Payload capacity: 350 kg
Wing loading: 29.5 kg/m²
Power load: 9.45 kg/hp
Speed at sea level: 125-130 km/h
Cruising speed: 106 km/h
ROC: 91 m/min
Ceiling: 3500 m
Endurance: 5.5 hours
Time to 1000m: 8.5 min
Time to 2000m: 20min
Armament: One 7.62mm machine gun
Bombload: 65 – 100 kg
Accommodation: 2
Grigorovich M-10
Smaller version of the M-5 built in 1916. Gnome Monosoupape engine.
Grigorovich M-9 / Grigorovič M-9 / Shchetinin M-9 / GAZ M-9bis
In 1915 the leadership of the Fleet, encouraged by the success of the M-5, decided to ask Schetinin for a larger flying boat. The task of development was assigned to the technical director of DP Grigorovich. The main problem facing the builder was the selection of contours. In the search for the optimal hull, the M-6, M-7 and M-8 were be developed.
The Grigorovich M-9 (Russian: Григорович М-9, also known as the ShchM-9 or Gidro-9,) was similar to the earlier M-5, but featured larger dimensions and a more powerful powerplant. In general, it was a biplane with three sections and a single-pronged hull.
The double-spar wing was characterized by its large span and differed very little in construction from that of the M-5.
The hull true ribs and a thicker coating. During the development of the model a series of modifications were made to the lines of the hull. The first were characterized by presenting a convex bottom in the region of the rim (similar to those of the M-5) with lateral expansions in the form of three-sided plywood trunks, which is why they were known as “widened rim”. Subsequently, boats with a sharp keel and auxiliary deflectors in the region of the redient were built, 1.5 meters long and 0.1 m wide, which facilitated takeoff.
The weight of the empty aircraft was 1060 kg when it left the assembly workshops, but this increased during operation as the wood absorbed a certain amount of water and through different repairs. Compared to the M-5, the M-9’s rudder was considerably larger in size.
This device could accommodate two or three crew members, divided between a forward cabin for the gunner that communicated with the wide flight deck located in front of the plans and that housed the pilot and the observer seated side by side. In a two-man configuration the forward gunner position was occupied by the pilot on the right (observer), who crawled into the nose position. On some occasions the crew consisted of three people. A Ruzie radio station was installed in the cabin.
The prototype was powered by a 140hp Salmson engine, but the main propulsion version featured a 150hp Salmson Canton-Unné liquid-cooled radial engine which featured radiators mounted on each side. As alternative power plants, Salmson 130 and 160 hp, Renault 220 hp and possibly Hispano-Suiza 140 hp were installed in a few examples. The engine was installed on a wooden frame fixed to the links between the wings and the fuselage.
The prototype was characterized by the presence of a spherical fairing covering the fuel supply tank, the oil tank and the front part of the engine. In later specimens, the 15-liter feeding tanks were installed in the space between the inter-wing supports. The main fuel tank, with a capacity of 225 liters, was located in the fuselage, behind the cockpit. The fuel supply was carried out by air pressure in the main tank, obtained through the use of a compressor. To control this process, a special manometer was installed that could be observed from the pilot’s position, turning the head backwards.
The radiator was generally located on either side of the engine and two types were used: trunk and flat, sectioned.
Armament was generally composed of a Maxim or Lewis machine gun located on a tripod. In a certain number of examples, a 20 mm Oerlikon cannon was installed at the bow, destined to beat small naval units, which made the M-9 the first flying boat in the world to use the cannon as a weapon. The Hotchkiss cannon was also used on some examples. Under the lower wing were four mounts capable of carrying a combination of bombs of up to 100 kg.
In 1917, a 37 mm “Pyuto” gun built by the Obukhovsky factory was installed in the bow of the M-9. A production of 50 with this armament was planned, but those plans did not come to fruition.
The first prototype of the M-9 was ready in November 1915. It was winter and in Petrograd and impossible to carry out the tests, so the plane was sent to Baku, to be tested in the Caspian Sea. The maiden flight was carried out on January 9, 1916 at Baku.
The tests, carried out between December 25, 1915 and January 9, 1916, showed good seaworthy conditions and response to controls in the water.
The hull was capable of operating with waves of up to 0.50 m and both take-off and landing were smooth. In the air the M-9 was stable and easy to pilot. In relation to other flying boats of the time, it was characterized by having a good load capacity.
Based on the excellent opinions issued by the test pilots on February 4, 1916, the Schetinin Factory received the request to prepare 50 M-9 copies with deliveries for June 5 of that year. Later another request for 65 machines would be made. with deliveries in August and shortly thereafter another request for 165 M-9s to be delivered in November.
The increase in orders for the M-9 led Schetinin to consider increasing its production capacity. For the development of the tests, the PRTV developed an experimental test station on Krestovski Island in Petrograd with equipment to lower the boats into the water. Another similar station was created in Sevastopol ‘s Kruglaya Bay, where it was hoped to build a branch for aircraft construction and upgrades.
In 1916 Schetinin decided to start developing the Yaroslavl branch, but after the October Revolution these works were abandoned.
Between April 1916 and mid-1917 at the PRTV factory, at least 212 M-9 examples were produced. By the middle of 1917, the aviation of the Black Sea Fleet had received more than 100 units and that of the Baltic Sea some 86 copies. For the creation of this model the Russian Naval Staff awarded Grigorovich the Holy Vladimir Order of the 4th level.
In May 1918 the Schetinin Factory received the name “Gamayún” (by virtue of its telegraphic address). In this year the factory received the task of building 15 M-9 units and on September 19 a new order was received for 40 units. A certain number of copies would be completed in the years of the Civil War. The last M-9s were delivered to the fleet in 1923.
Up to 1923, about 500 copies of the M-9 were produced.
During the Russian Civil War, M-9s participated in the air defence of Baku, dropping approximately 6,000 kg of bombs and 160 kg of arrows. The aircraft also carried out photo reconnaissance, artillery spotting and air combat sorties.
The M-9 flying boat was used in the Baltic against German forces as a coastal reconnaissance aircraft and bomber and in the Black Sea, where it faced Turkish, Bulgarian and Romanian forces.
The main problem of the M-9 was the great resistance of its engine and radiators, so its speed reached about 110 km/h to about 100 km/h. This prevented it from being an effective competitor to the German Albatros fighters with floats, capable of reaching speeds between 150 and 160 km/h.
The M-9 was also used for the first experiments on sea shelve study, participating in the finding of new oil fields near Baku.
Nine M-9s were captured by Finland during the Russian Civil War. One was flown by a Russian officer to Antrea on April 10, 1918. It sank the following day during type evaluation. Eight more were taken over at the airfields at Åland and Turku. The aircraft were used until 1922 by the Finnish Air Force.
Operators were, the Russian Navy, White Army, Finnish Air Force, and Red Army. Several samples of M-9 were purchased by the United States, and the United Kingdom purchased its drawings and technical documentation.
By May 1, 1923, the first of the M-9bis series, with number 1717, was ready and by the beginning of June a commission chaired by the representative of the Scientific Committee of the VVF, the engineer Yermolaiev, developed the first tests of evaluation. The flights were carried out by the naval pilot V. G. Chuxnovski.
In 1921 GAZ No.3 one of the M-9 was modified with the installation of a 220 hp Renault engine. The prototype was successfully tested and would soon be renamed M-9bis. On July 19, 1922 at GAZ No.3 “Krasni Liotchik, a commission of the aeronautical department of the Main Directorate of the Military Industry (GlavBoyenProm) met, which studied the factory’s capabilities and analyzed the possibility of building eight new aircraft with M-9 hull and Renault powerplant. In August of that year, during the establishment of the industry’s production program for 1922 – 1923, the construction of 56 M-9bis copies was approved.
Taking into account the differences between the modernized model by Grigorovich and the M-9bis, the commission decided to approve the new name M-24, classify it as a naval reconnaissance hydrofoil and gave a positive assessment of the aircraft’s maritime and aeronautical characteristics. It was decided to authorize its serial production as the M-24.
In 1918 all Petrograd aviation factories were unified into the Petrograd Unified Aviation Factory. On June 16, 1921, the “Gamayún” factory (former SS Schetinin PRTV) was practically destroyed by fire. All the equipment and materials that could be salvaged were transferred and distributed between the RBVZ and the old Lievediev factory. After the restructuring of the economy, this unified factory would be renamed the State Aviation Factory (GAZ) No.3 “Krasni Liotchik” (Red Pilot).
In this factory, even before the arrival of Grigorovich , it was decided to continue the production of the flying boat M-9. In 1921 in one of these assembled examples a 220 hp Renault engine was installed. The prototype was successfully tested and would soon receive a new designation M-9bis.
Designed by RM Kholotov, the modified prototype was successfully flown for two years and the pilots claimed that in relation to the M-9 the new model presented better flight characteristics and behaved better in the water. The recorded speed reached 130 km/h, well above the 90-100 km/h recorded by the M-9 floatplanes in operation.
Motivated by this positive evaluation, the “Krasni Liotchik” factory received a request from the naval aviation directorate to modify another three examples, but soon in its operation it was shown that the structural resistance of the model did not respond to the new engine power and worsened the operation on water. It was concluded that it was not enough to increase the engine power, it was necessary to make modifications to the flying boat in order to achieve an effective result.
M-9s intervened in the Baltic, some from the Orlitza hydro transport and others from the bases on the island of Saaremaa and Tallinn. The first copies would arrive at these units in May 1916.
Led by Jan Nagursky, nine M-9s from the Kilkond (now Kihelkonna) naval airbase bombed the German base at Angern in June 1916. Intercepted by German fighters, Nagursky broke contact by looping, a maneuver never performed to date in a flying boat. On September 17, 1916 Nagorsky repeated the stunt on his own base and with maximum payload on board. Two loops were made with a passenger on board. The record was confirmed by the council of the Imperial Flying Club on November 12, 1916, being considered world-wide.
In the Baltic the absence of a machine gun covering the rear hemisphere caused heavy losses when engaging new enemy fighters, so from 1917 in the Baltic it was necessary to accompany the M-9s with Nieuport-17 and Nieuport-21 ground fighters. Some pilots independently tried to solve this problem by installing backward-firing machine guns on the lower wing (above or below) and creating a whole range of combat methods in order to achieve some result with them.
In this period, Russian pilots managed to claim at least a dozen kills of enemy aircraft against similar losses of their own. On July 12, 1916, an air combat took place between an M-9 piloted by Lieutenant PA Turzhanski and five German flying boats, one of the latter being shot down.
In July-August 1917, some 30 M-9s (with SchS registration) and 13 M-15s (with SchI) were located on these bases, with the following distribution:
Brigitovka Station (Revel)
4 М-9 (ШС-52, 65, 61, s/n), 4 М-15 (SchI-10, 12, 14, 15)
Kilkond (Kihelkonna) Station
8 М-9 (SchS-59, 37, 60, 49, 28, 16, 39, 38), 4 М-15 (SchI-7, 1,8, 13)
Gapsal Station (Japsalu)
4 М-9 (SchS-22, 25,51,62)
Gogenholm Station (Reizi)
3 М-9 (SchS-35, 46, 47)
Tseriel (Syare) Station
1 М-9 (ШС-50), 4М-15(SchI-2, 4, 5, 6, 9, 11)
Abo Station (Turku)
6 М-9 (SchS-44, 53, 57, 66, 67, s/n)
Metiluoto Station
2 М-9 (SchS-56, 58)
Arensburg Station (Kingisepp)
1 М-15 (SchI-3)
Raymo Station
3 М-9 (SchS-45,69, s/n)
Degere station
4 М-9 (SchS-23,33, 34, 43)
By the end of 1917, in the Baltic naval aviation , it was considered that the M-9 could only be used where there was no enemy strength in the air, since the absence of rear defense and low vulnerability made it an easy prey for enemy fighters.
Starting with the 1918 offensive, the number of M-9 flying boats available decreased considerably. After the evacuation of Finland there were about 10 M-9 copies.
A number of examples were taken into service with the Red Air Fleet in the Petrograd region.
M-9s from the Black Sea entered service with the air divisions based in Odessa and Sevastopol. At the beginning of 1915 the seaplane carriers Alexandr I and Nikolai I entered service in the Black Sea, constituting a division of hydroplane cruisers together with various support vessels. Each hydro transport was equipped with eight flying boats, initially Curtiss F and Grigorovich M-5. Mid 1916, these hydrocanoes were replaced by M-9, which were lowered into the water and hoisted on board by means of large cranes supplied on the ship itself. Later, some merchant ships of Romanian origin were converted into transport ships for M-9s.
The Grigorovich M-9s, both from their transport ships and from installations on the mainland, carried out a large number of raids against shipping and naval bases in Bulgaria, Romania and Turkey, conducting air raids over the Bosporus, Varna, Constanta and other military objectives. During the summer of 1916 several M-9s were fitted with Oerlikon guns for anti-ship missions.
In the Caspian Sea during 1918 and early 1919, two M-9 were used, of which at least 1 was used in military operations against Turkish forces. By the end of 1922, one of these flying boats was used in the Baku area for the purpose of carrying out studies on the sea. Flying at altitudes of 500 – 900 m, the pilots managed to find new oil deposits.
The M-9s took an active part in the Russian Civil War. White forces used 5 M-9s in the Black Sea area in the summer-autumn of 1919. Three other examples were made airworthy in the Don Air Division.
Until mid-1919, some 40 examples of the M-9 were prepared at the “Gamayún” factory (former PRTV of SS Schetinin), which entered service with the Baltic Sea Air Brigade.
A distinctive feature of the Civil War in Russia was its development along the course of the great rivers (Northern Dvina, Dnieper, Volga, Kama). The fundamental milestones of their performance were marked by some devices flown by Bolshevik pilots: they operated from special barges anchored in the Volga and Don rivers. These barges were towed to the areas of operations when their presence was required and, once there, the M-9s were floated on the surface of the river using purpose-built ramps.
Particularly famous was the “Komuna” barge, capable of carrying 6 flying boats in a special hangar and belonging to the Volga Air Division. In April 1919 this division’s flotilla consisted of 6 M-9s, 2 M-20s, and one Nieuport-23 wheeled fighter. The total number of M-9s used by the forces of the Red Air Fleet in 1920 totalled about twenty examples. By 1921, this figure was maintained thanks to constant repair and maintenance actions, but from then on it gradually decreased.
In the middle of 1917 in the Black Sea 48 M-9 were registered. Beginning in the fall, the M-9s changed owners on several occasions, which was reflected in their availability. In the spring of 1918, during the Austro-German occupation of the Black Sea, these forces occupied about 40 examples, but practically did not use them, so that by 1919 there were very few left in flight conditions.
After the evacuation of the Russian troops from Finland, there remained about 10 M-9 that were used by the Air Force of this country. One of them was flown by Russian officers to Antrea on April 10, 1918 and would be sunk the next day during evaluation flights of the model. At least 8 copies were deployed to the airfields of Åland and Turku. The M-9 remained in service in Finland until 1922.
The excellent characteristics of the M-9 attracted the attention of other countries. Several examples were sold to the United States. The plans and technical documentation for a possible series production were delivered to England, which never came to fruition.
By the beginning of the 1920s, the few examples in flight condition began to be withdrawn from active service. A certain number of copies remained in service until the middle of that decade, basically in training functions and fishing patrol flights.
It is known that in December 1927 an M-9 with civil registration R-RDOM was in operation at the OSOVIAJIM in Ulyanovsk and another M-9 with the word Activist painted on the sides was kept unarmed in the warehouses.
By 1923 the factory would achieve another development using the same power plant, which was called the Grigorovich M-24.
The management of the Navy, convinced that it had an excellent flying boat, never submitted requests for improvements, so no development versions were made during its use with the Fleet aviation. The main changes were linked to the use of different types of radiators, engines, bracing cables and minor detail modifications, but in general all the M-9s produced differed little from the original prototype.
Among the main modifications of the M-9 are:
Kukuranov’s M-9: In 1919, at the request of the pilot AP Kukuranov, a modification of an M-9 with a 130 hp Salmson engine and much thicker profile wings was made. According to VL Korvin-Kerber, who flew this aircraft in 1921, it outperformed the 150 hp Salmson-powered production models on many metrics.
M-9bis: A rather different version was developed by engineer RM Jolostov in Petrograd in the winter of 1919 (1921). This version featured a 220 hp Renault powerplant and reached 130 km/h. It was not produced in series because in 1923 the M-24 appeared.
M-19: According to Shavrov a development of the M-9 with a wingspan of 13 m, a length of 8.50 m and a wing area of 48 m²; powered by a 160 hp Salmson engine
M-23bis: Experimental model developed on the M-9 with a 280 hp Fiat engine.
M-24: A development of the Renault-powered M-9 design appeared in 1923 and produced in certain numbers.
M-9
Engine: 1 × Salmson Canton-Unné, 111 kW (150 hp)
Wingspan: 16.00 m (52 ft 6 in)
Wing area: 54.8 sq.m (589.6 sq.ft)
Length: 9.00 m (29 ft 6 in)
Height: 3.3m
Empty weight: 1060 kg
Maximum takeoff weight 1 540 kg
Fuel and oil weight: 220 kg
Maximum load capacity: 480 kg
Wing loading: 28.10 kg/m²
Power load: 10.3kg/hp
Maximum speed: 110 km/h (59 knots, 68 mph)
Cruising speed: 98 km/h
Landing speed: 85 km/h
Service ceiling: 3,000 m (9,840 ft)
Time to 1,000m: 12min
Time to 2,000m: 30min
Range: 450km
Endurance: 3.5 hours
Crew: 2 – 3
Armament:
1x 7.7 mm MG or 1x 7.5 mm MG or 1x 20 mm cannon or 1x 37 mm cannon
Bomb load: 100kg
Grigorovich M-8 / Shchetinin M-8
According to Shavrov the Grigorovich M-8 (Russian: Григорович М-8) was a new prototype on the way to the M-9, in which the contours of the hull were once again modified with a higher recess (about 150 mm). In this case the prototype did not even manage to take off from the water.
AO Alexandrov handles another theory since the following statement appears in a Navy document dated October 26, 1915:
“Currently at the Schetinin factory two large experimental flying boats with increased range are being built. At this time one of them (the minor) is ready and is in the testing stage…”
According to Alexandrov this document refers to the M-7 and M-8 models.
The idea of creating the M-8 as a large flying boat with a long range could respond to a request from the pilots of the Baltic Fleet. In the Naval General Staff, many plans related to naval aviation were related to the giant models of Igor Sikorski and their possible modification to navalized versions. Unfortunately, the only example of the Ilya Múromets bomber in floatplane configuration with floats was destroyed by an accident caused by its pilot’s error during landing in the first days of the war.
At the end of July or beginning of August 1915 D. P. Grigorovich presented to the Aviation Committee of the Baltic Fleet the project of a biplane and twin-engine flying boat with an empty weight of 3.1 tons and a payload capacity of 2 tons. The large fuel capacity (970 kg) allowed it a range of 8 hours of flight at cruise power from its 600 total hp engines. The calculated speed was about 105 km/h.
On August 12, the military pilots supported the idea and proposed giving the aeronautical manufacturer an advance of 50% of the value requested to start the construction of the experimental prototype. The other 50% would be delivered once the specimen was finished and successfully tested, considering that the data presented could only reach a deviation of 10% with respect to the calculated ones.
On August 22, Captain 2nd Rank BP Dudorov, Head of the Aviation Department of the Baltic Sea Liaison Service , approved the idea, but expressed his disagreement with the proposed form of payment. Instead he proposed that the firm apply for a loan and deliver the engines of the requested power.
Everything indicates that SS Shchetinin put great hopes in the project, for which he ordered to start its construction at risk. It was also oriented to expand the factory with new workshops capable of accommodating large flying boats under its roof.
According to a report from the Naval General Staff (MGSh), issued on September 24, the model was built with two 220 hp engines, which would allow a horizontal speed of 95 km/h with a climb of 2,000 meters in 30 minutes. Cargo capacity was also reduced to only 1.7 tons, including crew, weapons and fuel capacity for 7 hours of patrolling. Neither the Navy nor the company were able to obtain the long-awaited 300-hp engines, but hope remained that they could be delivered before construction of the prototype was completed.
From then on, all the evidence that could link the fate of the M-8 disappears. Probably the requested power plant could not be obtained and the performance with the 220 hp engines ceased to be of interest to the Navy, but these are only guesses.
In a paper presented to a meeting of the Imperial Flying Club on November 25, 1915 , AO Alexandrov found some technical data on an airplane that he associated with the M-8. These data are the following:
Number of motors: 2
Total power: 600 hp
Take-off weight: 5100kg
Payload Capacity: 2000kg
Endurance: 8 hours
Fuel weight for 10 hours of flight: 970 kg
Armament weight in 5-hour flight: 650 kg
Armament weight in 10-hour flight: 135 kg
Crew: 5 people
Speed with maximum load: 105 km/h
Wingspan of upper plane: 33 m
Wingspan of the lower plane: 24 m
Height: 3.8m
Length: 14.6m
All Aero 