Borovkov/Florov advanced biplanes

[redstar72]

I've to say maybe we need to start a thread about Borovkov-Florow projects because I didn't know about the Aircraft 10 and 11 projects. A search in on the web shows a lot about the I-207. Are these advanced versions of 207?

Not quite, but in some way...

The I-207 program came to its final, but Alexei Borovkov and Ilya Florov didn’t think it was all over for the biplanes. They actually believed that biplane can fly as fast as monoplane… at least as fast! So, the “10” and “11” projects appeared…


Borovkov/Florov “Aircraft No.10”
Design date: 1940
Purpose: high-speed maneuverable fighter, escort fighter, dive bomber
Engine: 1x Shvetsov M-71 (1700/2000 hp); 1x Merkulov DM ramjet
Crew: 1
Wing span: 9.5 m
Length: 8.35 m
Wing area: 24.0 m2
Takeoff weight: 3500 kg
Wing loading: 146 kg/m2
Maximum speed without ramjet: 650 km/h
--//-- with ramjet active: 750…800 (840?) km/h
Climbing to 8000 m (with ramjet active): 8.0 min
Flight range: 800 km
Turn time: 14…16 seconds
Weapon: 1x 12.7 mm Berezin BS, 2x 7.62 mm ShKAS. Can be easily replaced with 2x 23 mm cannons.
Significant features: Cantilever biplane with no struts and wires. Upper wing is “gull” type, lower is “inverted gull”. The aircraft featured tricycle landing gear, because tail part was occupied by DM ramjet and there were no place for the tailwheel. The ramjet (already tested by Borovkov and Florov on the I-207/3) was used only for short time as a booster. When it wasn’t active, the inlets were closed by special doors.

Borovkov/Florov “Aircraft No.11”
Design date: autumn 1940
Purpose: maneuverable fighter only.
Engine: 1x Shvetsov M-71 (1700/2000 hp); 2x Merkulov DM ramjets
Crew: 1
Wing span: 8.5 m
Length: 7.85 m
Wing area: 22.0 m2
Takeoff weight: 3250 kg
Wing loading: 148 kg/m2
Maximum speed with ramjet active: 750…800 km/h
Climbing to 8000 m (with ramjet active): 6…7 minutes
Flight range: 800 km
Other technical data unknown.
Significant features: It was smaller and lighter derivative of the “10”. Instead of one large DM ramjet, it has two smaller ones placed side-by-side. The “11” was a taildragger back again, and the tailwheel was placed between the two ramjets.


Despite of high proclaimed performance, any of these projects wasn’t supported by both the VVS and NKAP. The common position was that biplanes belong to the past. According to Maslov, when Borovkov discussed his work with Yakovlev the latter said that any biplane will not get support anymore.

Source: Mikhail Maslov "Borovkov and Florov fighters". - Aviatsiya (Aviation) magazine Vol.2 (2/99), p.15-16.

P.S. It’s interesting that, according to Maslov, the DM letters stood not for Dvigatel Merkulova (Merkulov’s engine) but simply for Dopolnitel’nyi Motor (additional motor).

 

[Stargazer]

And what about this later 1941 design? What was it called? Was it ever built?

 

[redstar72]

It wasn't built, and almost nothing is known about it. Mikhail Maslov found the provisional sketch of it when researching Florov's 1940-41 documents in the archive. Even the designation isn't known.

 

[theponja]

Thanks a lot for the very detailed data redstar72. I wonder why they follow with the biplane. agility, size?

 

[Stargazer]

More about Aircraft '10', Aircraft '11', Aircraft '7211' and the I-207 in this excellent source on Florov:

Source: http://www.ciam.ru/file/Image/book_qwe_002.pdf

 

[hesham]

Hi,


here is the Borovkov/Florov I-207 with rocket engines,and a drawing to I-207/4.

 

[borovik]

Nonsense, confusion.
On I-207 had no rocket engines.

 

[hesham]

My dear Borovik,

here is its three pages from;

Наша авиация в 1941 году: Причины катастрофы
(Война и мы. Авиаколлекция)

 

[borovik]

Hi,


here is the Borovkov/Florov I-207 with rocket engines,and a drawing to I-207/4.

And?
Hesham I know the history of this aircraft ...
Where did you get information about using to them of rocket engines?

 

[hesham]

OK my dear Borovik,


I thought they are a rockets,but they are a weapons right ?.

 

[Avimimus]

Is No.11 the fastest biplane designed?

 

[borovik]

I-207 №11
Maximum calculated speed at an altitude of 5830m without the inclusion of a ramjet (without bomb load) was 654 km / h.
With the use of two additional ramjet engines by Merkulov calculated speed should reach 750 km / h.
(It may be overly optimistic))

 

[hesham]

I-207 №11
Maximum calculated speed at an altitude of 5830m without the inclusion of a ramjet (without bomb load) was 654 km / h.
With the use of two additional ramjet engines by Merkulov calculated speed should reach 750 km / h.
(It may be overly optimistic))

Good Info my dear Borovik.

 

[hesham]

Hi,

Èñòîðè÷åñêàÿ ñåðèÿ - Òåõíèêà - ìîëîä¸æè 1992-01-02, ñòðàíèöà 18

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