*Soviet rocket and jet airplanes - BI and others

[BIGpanzer]

I found some info about interceptor fighter MiG-13 (I-250) with mixed power plant. Tomorrow will try to post it here. It was written that small amount of MiG-13 were used in the Air Defence Units of Navy aviation (Baltic and North navies) along with Yak-9, La-7 and lend-lease P-47 Thunderbolt fighters just after the WWII and till 1950.

Does somebody know in which air regiments or squadrons those quite unique fighters were used? Also how many MiG-13 were produced? I couldn't find the answers on these questions.

Thanks, BIGpanzer

[Skufr]

Two prototypes and a total of sixteen production models were produced. The latter equipped an evaluation unit at Skultye, Riga. Entered service in late 1948 I believe, a was phased out in 1950.

[BIGpanzer]

Thanks, Skufr!
Interesting info, I didn't know about that before. What is the source of your information?

Here is what I found about MiG-13 and promised to post here.
All-metal I-250 ("N" or also MiG-13) was the first jet airplane, developed in the design office of Mikoyan and Gurevich since 1944. In contrast to Yakovlev's and Lavochkin's fighters with mixed power plant, installed on serial fighters Yak-3 and La-7, I-250 had completely new design. Because of the absence of native ready to use jet engine in 1944, I-250 had mixed power plant also (VK-107A engine with additional driving shaft to the compressor of the ramjet, which located along the fuselage, under the VK-107A engine and the cockpit). Nozzle had adjustable hydraulic leafs. The compressor of the ramjet was used also for increasing the height ability of VK-107A engine. Both engines used gasoline as a fuel (1 x 420 l tank - in front of the cockpit; 2-4 x 100 l - in center section). The technicians called I-250 "boot" because of the fuselage shape.

The first prototype was built in February 1945 and tested in flights during March-May 1945. 825 km/h was reached at 7800 m altitude with operated ramjet (the highest speed in USSR); the speed was 677 km/h at the same altitude with only VK-107A operated. In May 1945 over the Central Moscow airfield the stabilizer was destroyed because of large g force at high speed and low altitude, the pilot was killed. But the mixed power plant worked excellent during all test flights.

After modernization of I-125 the small series of MiG-13 (serial name of I-250) was produced after the WWII. MiG-13 had the new enlarged tail assembly. Eight of MiG-13s were tested by pilots of 176th Guard Nevsky fighter regiment (324th division of Air Defense, Moscow region) since September 1946 in the course of preparation to air parade in 7 November 1946 along with new MiG-9, Yak-15 and La-150 (the parade was abolished because of bad weather). Later MiG-13s were used by navy aviation of the North and Baltic Navies till 1950 for escort of torpedo bombers, when much more better jet fighters MiG-9 and MiG-15 replaced them. The mixed power plant with compressor ramjet was the last step on the way from propeller to jet aviation. The pilots didn't like MiG-13 very much because of large weight, complicated take-off and huge amount of the monitoring devices at the pilot's cockpit.

Specifications of MiG-13: crew 1 man; flight weight 3931 kg; dimensions 8,185 x 9,5 m; engines 1 x VK-107A (1650 hp) + 1 x ramjet by Kholshevnikov (1150 hp); speed 825 km/h; climbing rate ~19,5 m/s (5000 m/3,9 min); ceiling 11900-12000 m; range 1818 km; armament 3 x 20 mm B-20 cannons (160 shells each).

MiG-13 was lighter and better armed than Su-5 developed at the same time. The American Ryan FR-1 "Fireball" (66 were produced since March 1945) with R-1820-72W engine (1425 hp) + English J31 jet engine (726 kgs) was less high-powered and high-speed (only 645-686 km/h with operated jet engine), also more heavy (4806 kg).

More photos of the I-250 (MiG-13):
http://www.airwar.ru/image/idop/fighter ... ig13-2.jpg
http://www.airwar.ru/image/idop/fighter ... ig13-4.jpg

Good detailed drawing of I-250:
http://www.airwar.ru/image/idop/fighter ... ig13-2.gif
Good colour picture of I-250:
http://techmol.narod.ru/TM/IST_SER/1984/04_.jpg

Photo of the Soviet interceptor fighter with mixed engine I-250, MiG-13 or N (1945-1946, 12 copies)
is from http://www.ldomino.ru/russia/mikoyan/i/ ... i250_4.jpg

[varjag]

An ugly duckling indeed - didn't the Russkies know about the number THIRTEEN?

[BIGpanzer]

Hello, Varjag!
Yes, the design of MiG-13 because of compressor ramjet looks strange, I wrote that technicians called it "boot" . Anyway there were a lot of different strange designs in experimental aviation.

I believe that Soviet pilots knew about the number "13" Pilots from all over the world are very superstitious. But it was written in some sources that the name MiG-13 appeared later only in historical aviation literature, in 1940s it was called I-250 or "N" as experimental fighter, not serial.

Truth to tell, MiG-13 was really unlucky fighter. It appeared a little bit late, during the first flights of serial jet fighters, so could't be recommended to large serial production. 40 I-250 were planned to produce as serial fighters in addition to already existed 10 experimental. But a lot of technical problems occured during the attempts to organize the serial production of I-250, especially with setting up of its oil cooler. I-250 even didn't finished official test, only factory tests. So, probably, only 10 experimental I-250 were produced, 8 of them were tested in Air Forces as some sources report.

But nevertheless I-250 played a great role in the history of jet aviation - one of the first axial compressors, regulated nozzles and high-temperature materials were tested on I-250.

[BIGpanzer]

The first Soviet serial jet fighter was MiG-9 (I-300) with two jet engines (installed in fuselage under the wing and cockpit, with nozzles under the tail - original and unusual scheme for 1940s, but such compact configuration had excellent aerodynamic). At first two German trophy engines BMW-003 were used on experimental I-300, later - Soviet 800 kgs RD-20 (on serial MiG-9). The first flight took place on 24 April 1946 and on 18 August 1946 the first MiG-9s were shown during the air parade in Moscow. Only the late model - MiG-9M had pressurized cabin and ejection seat. MiG-9 was exploited by Air Force not long and was replaced by more modern fighters with swept-back wings.
Armament 1 x 37mm N-37 + 2 x 23mm NS-23, flying weight 5040 kg, speed 911 km/h, range 800 km, ceiling 13500 m.

In parallel jet fighter Yak-15 was developed at Yakovlev's aircraft design office, based on the construction of the famous and prevailing WWII fighter Yak-3 for better retraining of the pilots to jet flights. The aerodynamic scheme was similar to MiG-9, but only one jet engine (RD-10, 960 kgs) was used. The first Yak-15 was built in autumn 1945. The first flight took place on 24 April 1946 (the same day as MiG-9's flight took place). Yak-15 also was shown during the air parade in Moscow (18 August 1946). Yak-15 was serially produced in 1946-1947, but because of not high thrust-to-weight ratio Yak-15s were used mainly as training aircrafts.
Armament 2 x 23mm NS-23, flying weight 2742 kg, speed 805 km/h, range 510 km, ceiling 13350 m.
Both MiG-9 and Yak-15 keep safe in the Russian museums, as some sources report.

Also at the same time La-150 (with RD-10 engine, 900-1100 kgs) was developed at Lavochkin's aircraft design office, according to the same resolution of the government, as MiG-9 and Yak-15 were developed. The first flight took place in autumn 1946. Only small series was built, because the specifications were worse than MiG-9 and Yak-15, especially the small amount of fuel on board.
Armament 2 x 23mm NS-23, flying weight 2961 kg, speed 850 km/h, range 700 km, ceiling 12500 m. Speed 950 km/h was reached with modernized RD-10 jet engine.

It should be noted that WWII prevented the designing of jet engines in USSR (first Soviet experimental jet engine S-18 by engineer Lulka was laid up in 1941, Lulka developed tank engines during the war). When the WWII ended, Soviet engineers decided to modernize trophy German jet engines BMW 003 and Jumo 004 (used on Me 262) and began their production under the names RD-20 and RD-10, correspondingly. Experimental Soviet S-18 was a little bit more powerful than German jet engines, but never used by airplane before and was technological not refined.

Photo of postWWII jet fighter Yak-15 (1945): http://gv470iap.narod.ru/planes/yak-15/yak-15.jpg
Photo of postWWII jet fighter MiG-9 (1946): http://www.testpilot.ru/russia/mikoyan/ ... ig9_05.jpg

[BIGpanzer]

As for the first Soviet jet bombers, I already wrote shortly about experiments with Pe-2 and rocket engine RD-1 (300 kgs) during WWII.

In 1947 the jet engines Rolls-Royce "Nene-1" were bought in UK and installed on serial WWII-period bomber Tu-2 instead of its usual 2 x Ash-82. "Nene-1" was produced in USSR as RD-45. Later the construction was changed (modified elongated fuselage with additional tanks, nose-wheel) and the new bomber was named Tu-12 (first flight took place on 27 June 1947, flight weight 14700 kg, engines 2 x 2270 kgs "Nene-1", speed 783 km/h, ceiling 11360 m, range 2200 km, armament - 1 x 23mm + 2 x 12,7 mm + 1000-3000 kg of bombs). Several experimental Tu-12 were produced.

In 1945 the project of jet bomber RB-17 (BM-24) with four RD-10 (German Jumo 004) was developed at Myasishchev aircraft design office.

In 1947 the experimental Su-10 with four Soviet 1500 kgs TR-1A jet engines was built (850 km/h, 12000 m, 1500 km).

I believe that the first serial Soviet jet bombers were Tu-14 and famous Il-28 (1948)

Photo of the postWWII jet bomber Tu-12 (1947): http://www.airwar.ru/image/idop/bomber/tu12/tu12-4.jpg

[Skufr]

Thanks, Skufr!
Interesting info, I didn't know about that before. What is the source of your information?

You´re welcome.

My information is based on the article "Soviet Mixed-Power Fighters 1939-1946" by Yefim Gordon and A. Dexter, printed in Wings of Fame Volume 15, and "The Complete Book of Fighters" by William Green and Gordon Swanborough. They both agree that 10 aircraft were ordered for the Red Square flypast on October Revolution Day in 1945. Gordon/Dexter claims that all 10 were ready in time, while Green/Swanborough writes that only nine were ready. Green/Swanborough further writes that these nine plus seven more were completed against an order from the Naval Air Arm while Gordon/Dexter only writes that 16 were completed and delivered. It adds up to 16 aircraft in any case.

[BIGpanzer]

Hello, Skufr!
Good info and excellent literature sources!
But I just want to make clear for myself the question about amount of I-250 (MiG-13).
Some Internet sources report that only 8 I-250 were produced as experimental series. So I made some research, using several sources, and here is what I found :roll: :

1. Prototype I-250 No. 01 was produced in February 1945 by the aircraft plant No. 155 and passed factory test since April 1945 (first flight took place on 4 April 1945). During test flights many technical defects in compressor, oil radiator and hydraulics of undercarriage were found and removed. On 3 July 1945 (24th flight of I-250) the speed 820 km/h was reached. I-250 No. 01 crashed on 5 July 1945 over the central Moscow airfield (pilot A.Deev was killed because of low altitude not enough for bailing out).

2. Prototype I-250 No. 02 was produced by the aircraft plant No. 155 and passed factory test since May 1945 (first flight took place on 26 May 1945). It also had some problems with engine, so usually during factory test till the crash of the first I-250 only one I-250 (No. 01 or No. 02) made flights. Another was under repair. The stabilizer of I-250 No. 2 was strengthen after the catastrophe with I-250 No. 01. But on 18 October 1945 the oil pressure vastly decreased at the altitude 1500 m and the pilot Chernoburov landed No. 02 at the southwest outskirts of Moscow, I-250 No. 02 was repaired then. On 12 July 1946 the fire in piston-engine occurred during the flight, the pilot could land, but the I-250 No.02 heavily damaged and didn’t restore.


3. In July 1945 the aircraft plant No. 381 began to prepare for serial production of I-250 (10 were planned to produce, according to the order from 27 July 1945). According to the order from 26 February 1946 the aircraft plant No. 381 should produce 40 I-250 as army series in addition to 10 as experimental series. But the time of delivery of engines was several times frustrated by engine engineers from another plants.

So in May 1946 the situation with serial production of I-250 was the following:
No. 3810101 – was built in 25 December 1945 with model engine. Used as assembly standard.
No. 3810102 – was built in 6 January 1946. During the test flight in 12 March 1946 the destruction of the compressor blades occurred. The engine was removed and sent for repair.
No. 3810103 – was built in 26 January 1946. Engine was tested in February 1946. Problems with oil filter occurred, so the engine was also removed for repair.
No. 3810104 – was built in 7 March 1946, but without compressor.
No. 3810105 – was built in 8 March 1946, also without compressor.
No. 3810106 – was at the final stage of the assembling, still without engine.
No. 3810107 – was at the final stage of the assembling, still without engine.
No. 3810108 – was at the final stage of the assembling, still without engine.
No. 3810109 – was at the final stage of the assembling, still without engine.
No. 3810110 – was at the aggregate stockpile stage of the assembling.

All 10 I-250s in May 1946 didn’t have engines and wings (wings were removed after discovery of some defects and were made anew).

Then:
No. 3810101 – was used as stand for the engine testing since 1 August 1946, the wings were cut off.
No. 3810103 – was finished in the beginning of October 1946.
No. 3810105 – was completely finished in September 1946, engines worked very well without any problems. 3 flights were made till the beginning of October 1946. In 2 October 1946 the fighter was a little bit damaged during the landing in fog and strong wind at the airfield of Flying Research Institute of Air Forces.
No. 3810106 – was finished in 1 October 1946.
No. 3810107 – was sent in 19 June 1946 to Moscow Aviation Institute for the tests.
No. 3810108 – was finished in 24 July 1946 and used for the constructional work during the preparation for army series production at the aircraft plant No. 381. It was planned to use it during air parade in 18 August 1946, but the first flight took place only in 11 August 1946. During that flight the short circuit occurred and the fighter was under repair till 15 September 1946. In 30 September 1946 the fighter was completely ready.
No. 3810109 – was finished in September 1946. In 21 September 1946 the problems with VK-107R propeller engine occurred during the ground tests. But then the pilots made 3 successful flights till the beginning of October 1946. In 3 October 1946 it was sent to Flying Research Institute of Air Forces.



So only eight I-250 from ten produced as experimental series (without No. 3810101 and No. 3810107) were sent to Flying Research Institute of Air Forces till October 1946. But 21 were planned to produce and sent – this plan was completely frustrated.

Skufr wrote:
They both agree that 10 aircraft were ordered for the Red Square flypast on October Revolution Day in 1945.

This is a mistake or misprint, because there were no jet or mixed engine fighters ready in November 1945 for such important mission.
The Soviet government decided to show the new jet MiG-9, Yak-15, La-150 and mixed engine I-250 at the air parade 7th November 1946 in Moscow (29 anniversary of October Social Revolution). The pilots from 176th Guard Nevsky fighter regiment (324th fighter division of air defence) trained at I-250 during the preparations to air parade since 10 October 1946. Five fighters I-250 No. 3810102, No. 3810103, No. 3810104, No. 3810106, No. 3810108 were used during the training flights till 29 October 1946. I-250 No. 3810105 damaged landing gear during the landing in 12 October 1946, was sent back to the plant and was under repair till 23 October 1946, but couldn’t be send to Flying Research Institute of Air Forces because of bad weather. I-250s No. 3810109, No. 3810110 were ready at the plant No. 381 in the end of October 1946.
Unfortunately, because of bad weather the air parade was abolished.

The marshal of Air Forces R. Vershinin asked aircraft plant No. 381 to take all eight I-250s back for removal 12 found technical defects. In 2 December 1946 the plant engineers started this work. The terminal decision of Air Forces was that I-250 was unstable during take-off and very hard for mastering by pilots, its mixed engine had many defects and was already became out of date. According to the order from 29 November 1946 the rest TEN I-250 should used as testing aircrafts at the plant No. 381 and Flying Research Institute of Air Forces.

But on December 1946 the plant engineers began to prepare two I-250 from the experimental series to official test. Another eight were preserved. 19 September 1947 I-250 No. 3810102 was sent for test at the Research Institute of Navy Aviation (Skulte, Riga). The time of flight from Moscow to Riga took 2 h 15 min. I-250 No. 3810102 had new fuel tanks. Till 21 January 1948 6 flights were made at Skulte airfield. 3 April 1948 the official test was stopped because of many defects. Probably, all eight I-250, which was still sent to Navy Aviation were used only as visual aids at navy colleges and never used as real fighters because of difficulties with engine service. The resource of the propulsion system was only 35 hours. And already excellent serial supersonic fighter MiG-15 appeared.

So, only two prototypes and 10 experimental I-250 were produced (12 total), according to those archive data, I found.
Best regards, BIGpanzer