Arkhangelsky high speed bomber SBB-1 and dive bomber SBB-2

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Hi! Arkhangelsky high speed bomber SBB-1 and dive bomber SBB-2.
http://www.airwar.ru/enc/bww2/sbb.html
http://eroplany.narod.ru/bibl/shavrov2/chr1/p1/sb1.htm
http://alternathistory.com/pikiruyushchii-bombardirovshchik-arkhangelskii-b-2-sssr
http://xn--80aafy5bs.xn--p1ai/aviamuseum/aviatsiya/sssr/bombardirovshhiki-2/bombard-1920-e-1940-e-gody/pikiruyushhij-bombardirovshhik-sbb/
"In parallel with the development of SB-RK(later called Ar-2) with engines M-105 KB Arkhangelsky began to develop a new high-speed near-bomber SBB. First, the new aircraft had an index C (under this designation the airplane was purged in TsAGI), but soon the index of the car was replaced by B. The aircraft was conceived as a cardinal modification of the serial satellites with increased combat performance and continuity in production technology. When designing it, we used the experience of creating MMN , SB-RK, and later Ar-2 . The crew of the SBB included a pilot, a navigator and a radio operator."

"The main advantage of the new aircraft was the significantly improved aerodynamics. The overall configuration and combat scheme of the B bomber were similar to the SAT aircraft, but with a two-keel plumage. In order to "maximize the speed of the aircraft," the load per unit area of the wing in the normal version of the combat load was brought to 149 kg / m2 and to 162 kg / m2 in the overload. In this connection, the wing area was reduced to 40 m2. The wing became shorter and slightly narrower than the wing of the SB. At the same time, to ensure the required landing speed, it was supposed to use the guards of TsAGI, which was a cross between the usual flaps and Fowler flaps. The profile of the wing was chosen to be of the NACA-22 type with a relative thickness at the root of 14.7% and at the end of 8%. "

"As the main engine of the power unit SBB was considered M-105 with a turbocharger TK-2. In addition, it was planned to use the M-106 engine. By this time, the M-105 had already passed 50-hour state tests, and the turbocharger TK-2 was installed on a SAT aircraft with M-103 engines for flight tests. n the future, in order to further improve the aerodynamics of the aircraft, it was planned to install the M-105TK inverted. In this case, the layout of the engine installation and the radiator was improved and a seat in the wing was released to accommodate the fuel tanks instead of the radiators.On this issue, there was an agreement with the engine builders of the 26th plant. However, in the future, from such an option, the power plant was abandoned, as it does not have significant advantages for a bomber aircraft over the traditional installation of a motor. "

"In November 1939, after discussing the layout of the SBB, it was decided to build an airplane. According to the Decree of the Defense Committee of 4 March 1940, two copies of the B-1(SBB-1) and B-2(SBB-2) were built. The first variant corresponded to the variant of the high-speed bomber, and the second - to the dive bomber. The B-2 aircraft differed from the B-1 with a wider fuselage and slightly different layout of the forward part of the fuselage. "

"On April 10, an order was issued on NKAP No. 309, according to which the entire design team of AA Arkhangelsky was transferred to the 32nd plant. Despite the difficulties associated with moving and settling in a new location, in the summer of 1941 a second version of the SBB, the B-2 dive bomber, was being built. It was assumed that, in comparison with the B-1, its maximum speed at the calculated altitude would be greater by 40-60 km / h.
At the same time, in connection with the successes of the 103 and 103U bombers during tests at the Air Force Research Institute, the interest of the military and NKAP in aircraft B was steadily declining, and the war that was started interrupted all sorts of work on this machine. Sam AA Arkhangelsky Order NAKAP No. 823 of August 9, 1941 was transferred to the aircraft factory No. 156 for the organization of repair and recovery of serial bombers SB. Later, AA Arkhangelsky's Design Bureau was evacuated to Omsk in October 1941, and the B-1 aircraft was sent to the rear in December 1941. What happened to him later is unknown. "


SBB-1(СББ-1)
Wing span, m: 16,00
Length, m: 12,27
Height, m: 3,52
Wing area, m2: 46,00
Weight, kg
Empty airplane: 4100
normal take-off: 5980
Engine type: 2 x PD M-105R
power, hp: 2 x 1050
Maximum speed, km / h
On the ground: 454
on height: 540
Cruising speed, km / h: 475
Practical range, km: 880
Lifting capacity, m / min: 788
Practical ceiling, m: 10100
Crew: 3

Ar-2(Ap-2)
https://en.wikipedia.org/wiki/Arkhangelsky_Ar-2
http://aviadejavu.ru/Site/Crafts/Craft20887.htm

Bottom picture explanation.
проект　пикирующего　бомбардировщика ; Dive Bomber Project

Вариант　пикирующего　бомбардироВщика　с　носоВой　частъю Без　козырька　пилота ; Dive bomber option with bow part Without the pilot's visor

So there were two designs for dive bomber.

 

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Ar-2 large three side view.
http://drawingdatabase.com/arkhangelsky-ar-2/

 

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SB-MMN.
http://massimotessitori.altervista.org/sovietwarplanes/pages/ar-2/mmn.html
"In the beginning of 1940, the Archangelskiy construction bureau in Zavod 22 aircraft factory worked hard on a perfectioning of the Tupolev SB bomber.
Two steps of development were taken in consideration:
• an aerodynamic improvement of the plane to achiece a top speed of 500 km/h at 6500 m with M-105 or M-106 engines;
• a full redesign of the plane to reach a top speed of 600 km/h.
Production tests and operational development proceeded with SB No. 18/206, using motors M-103 with TK-2 turbosuperchargers.
Zavod 22 was charged to build 3 SB with M-105 TK-2 engines within September 1940, but they found difficulties, and build only two SB-2-M105TK2 that failed to pass factory tests. One of them was later delivered to NII-VVS (The Scientific Institute of Air Force) for tests.
To improve the aerodynamics of SB, a new prototype was built.
This was the MMN (modified smaller lifting surface).
It featured:
• new smaller outer wing panels of simplified construction, with a 18.00 m span (instead than 20.33 m) and an area of 48.2 sqm (instead than 56.7 sqm);
• with two further 205 l tanks in the outer wing panels;
• a redesigned nose with wider trasparent surfaces and one ShKAS machine gun (instead of two);
• 2xM-105 engines of 2x1050 hp (instead than 2xM-103 of 2x960 hp);
• VISh-2E 3-blade propellers with starter dog and modified cowling;
• dual controls installed on the navigator's cabin;
• a dorsal MV-3 turret (instead than TUR-9) with one ShKAS 7.62 mm machine gun;
• a ventral MV-2 turret with a ShKAS replaced the LU hatch mounting;
• much enlarged flaps;
• a lowered vertical tail unit;
• a landing light in the leading edge of each wing;
• an emergency undercarriage extension system was installed in the cockpit.
In spite of all these efforts, the improvement in performances over the SB M-103 was neglegible and fully unsatisfactory, while the landing speed increased to 160 km/h.
The defensive armament was weaker than that of SB.
The prototype was tested in September 1939 by NII VVS.
On the whole, the result was deluding, and the only prototype, called Shchuka (pike) was allocated to Aeroflot.
However, the State Commission recommanded that many of the new characteristics of the SB-MMN should have been introduced in the production of SB bombers. "

 

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Ar-2
https://alchetron.com/Arkhangelsky-Ar-2-1748572-W
http://aviadejavu.ru/Site/Crafts/Craft20887.htm
http://massimotessitori.altervista.org/sovietwarplanes/pages/ar-2/history.html
"The SB-RK(Ar-2) was not only a further perfectioning of the unsuccessful SB-MMN, but it was projected for dive bombing too. "

"The operative life of Ar-2 was very limited not only due to its limited production, but also because a lot of them were destroyed or captured on the ground or sent to attack the enemy without any escort in the first days of war. According to official sources, 95 Ar-2 were lost during 1941.
Some authors regret the stop of production of Ar-2 in favour of Pe-2 because, if it's true that Pe-2 was 20-40 km/h faster and had a greater range, it's also true that the Ar-2 had better bombing qualities and was able to accept rough landings by far better than the Pe-2, many of which were written off in this way when their fuselage broke. "

SBB
http://massimotessitori.altervista.org/sovietwarplanes/pages/ar-2/sbb.html
"After the limited modernization of SB represented by SB-RK, the Archangelsky bureau was charged of a more radical redesign to reach a speed of 600 km/h.
In 1939, they worked on a new fast bomber for close support of ground troops, called Skorostnoj Bliznyj Bombardirowszczik (fast short-range bomber) rsp. abbreviated SBB-1.
The prototype SBB-1 was equipped with M-105R engines, like MMN and Ar-2. "

Bottom picture shows little different shape turrets.