During WWII some long-standing military disciplines (biplane fighters, battleship duels) went extinct. Others (submarines, radar, jet engines) were in a basic state in 1939, then highly developed during WWII and important afterwards. Still others (ballistic missiles, nuclear weapons) were entirely developed during WWII and important thereafter. Many, many other technologies were experimented with during WWII, failed for whatever reason, and were abandoned.
There is a final category that might be considered. This is a very tiny number of technologies which were developed entirely during WWII, actually worked, but were already overtaken by the time WWII ended.
MiG’s unique late-war fighter project would fall into this final small category. This plane was originally called project “N”, then I-250, and finally MiG-13.
bureaus and the Soviet system
The way the USSR’s warplane industry was organized during & after WWII was different than the rest of the world, and is often still poorly understood today. There were no “airplane companies”. Designs originated from design bureaus (OKB, in Russian) which were established by government decree and named after their lead engineer…..Pavel Sukhoi, Andrei Tupolev, and so on. One bureau, MiG, was unique in that it had two co-chairmen, Artem Mikoyan and Mikhail Gurevich.
(Trademark of RSK MiG, the successor Russian Federation company to the Soviet-era design bureau.)
Bureaus were not top-to-bottom set-ups, but rather just state-subsidized engineering shops. For example, MiG itself only had capacity to assemble two or three individual planes at any given time. If a bureau’s design was chosen, the actual order was built by an unrelated zavod (state-run factory), which might be hundreds of miles away.
From roughly the end of the Korean War until the end of the Cold War, the roster of Soviet bureaus solidified into ten “big players”, but it was not always this way. During aviation’s golden age, and then during WWII, bureaus rose and fell. Typically a bureauship would be granted to a promising engineer, and rescinded at will – normally for continued lack of successful designs, or (while he was alive) a tantrum by Josef Stalin. When WWII started, bureaus such as Polikarpov, Yermolayev, and Petlyakov were as notable on the world scene as Grumman or Northrop, but within 10 years they were completely gone and forgotten.
(The Yermolayev Yer-2 was the first Soviet bomber to hit Germany. After WWII, it was obsolete and used in the air-sea rescue role until 1949. This bureau had already vanished five years previous.)
As a communist entity, bureaus were not “corporations” and did not exist through profitability. Their ongoing existence was funded as a yearly expense in the national budget. When a need for a new aircraft was identified, the Soviet defense ministry spelled out it’s exact requirements, picked two or three bureaus, and chose the prototype that best matched the requirements. State funding to “competing” bureaus rose during the design phase and fell again afterwards.
(The Alekseyev bureau was once a rival of MiG and Sukhoi. The I-215 fighter flew two years after WWII. It was a failure and the bureau itself disbanded in 1948, having had no successes after WWII.)
If the lead designer retired or died, his bureau vanished with him. When Mikoyan passed away in 1970, Gurevich requested and received permission to continue the MiG bureau in it’s existing structure and name. This established the precedent of bureaus becoming permanent, and effectively blocked creation of new bureaus thereafter.
There were advantages and disadvantages to the western and Soviet systems. In the USA, if several aircraft companies bid on a Pentagon contract, the winner takes all. For the losers, money wasted on their failed bid could damage (or even bankrupt altogether) the company. Indeed this happened to Curtiss of WWII fame when their XF-87 failed three years after the war. As Soviet bureaus were subsidized, an unsuccessful bid was (at least in the short term) disappointing but irrelevant.
In the Soviet system, there was an unavoidable lag as the sluggish defense bureaucracy ironed out their requirements, shortlisted bureaus, picked a winner, then lined everything up with the independent zavods. These delays might be imagined as accumulating interest on a debt: in 1950, the USSR and USA were at parity in fighter design and technology – but by 1990, the Soviets had fallen almost a decade behind due to the “lags” at each leap in technology over the years.
In 1988, Mikhail Gorbachev established a “state profit” scheme were OKBs had to justify the stipends they received vs their productivity. The results will never be known because three years later communism, the bureau system, and the USSR itself all ended.
Obviously the most interesting thing about the MiG-13 was it’s engine. Called VRDK, (vozdushno-reaktivny dvigatel kompressorny’y, or air-reaction compressor jet), it was not a turboprop, nor a compound engine, nor a true jet. Today it is often referred to as a “motorjet”, the most basic type of jet engine, but this is not 100% appropriate either. Basically, the VRDK was it’s own thing.
The front end of the VRDK was a Klimov VK-107 liquid-cooled, 12-cylinder 1,650hp piston engine. This was already a proven powerplant during WWII, being used on the Pe-2 “Buck” tactical bomber and later versions of the Yak-9 “Frank” fighter. It turned a AV-10P-60 three-bladed propeller, another already-proven item.
(MiG-13 with cowlings removed, showing the Klimov VK-107.)
To the rear of the VK-107 was a clutch attached to a PTO shaft. This in turn ran to a compressor mid-fuselage, roughly underneath the cockpit. The compressor was fed by a nose airscoop that lead into an air tunnel, and a small secondary duct which fed up to the piston engine’s supercharger and oil cooler.
(The PTO shaft leading from the VK-107 to the compressor unit.) (photo via testpilot.ru website)
When engaged by the pilot, the compressor was powered by the piston engine and ran at a 13:21 ratio to the PTO shaft. The piston engine’s radiator sat horizontal just behind the compressor. Besides letting the rushing air cool it, it had a bonus effect of heating up and densifying the already compressed air.
Behind this was the combustion chamber, a structure of stainless steel with seven fuel injectors. These sprayed fuel into the compressed air and ignited it under pressure. MiG engineers stated the VRDK was limited to a maximum of 10 minutes of operation per flight, as there was no real method of dissipating heat other than the mass of the stainless steel.
Still behind this was a plenum in which the blend of heated air and combustion byproducts expanded into, thereby generating forward thrust. This chamber was not circular in profile nor was it aligned to the plane’s axis. As it was not a true jet, there was no real need for it to be.
Finally there was an exhaust to the rear. Clamshells closed over it when the VRDK wasn’t being used, to prevent a low-pressure drag zone forming behind the plane.
(MiG-13 with the clamshell doors partially closed over the VRDK exhaust.)
the plane itself
The rest of the MiG-13 was well-done but simplistic. This was perhaps intentional, as by the latter part of 1944 the designers may have been having second thoughts about the technology’s long-term viability. Perhaps there was a desire to just get the project complete. In any case, the design’s simplicity worked to it’s advantage.
The single-seat MiG-13 was 26’10” long with a 31’2″ wingspan. It weighed 6,166 lbs and had a range (in an average mission profile) of 427 NM, with a ceiling of 39,000′; adequate to intercept the B-29 Superfortress at it’s bombing altitude. It was of all-metal construction. The wings were double-spar internally, and had slotted flaps. All the fuel was internal; a 109gal tank in the fuselage and 26gal tanks in each wing.
The landing gear retracted inwards hydraulically and had 2’2″-diameter tires. As originally designed, the tail gear was supposed to have been a steel skid, later changed to a wheel.
During WWII, MiG planned to arm the plane in accordance with Soviet tactical air doctrine of the time: a single 23mm gun and two 12.7mm machine guns. After Germany’s defeat, it was thought that the next possible foe would be the USA’s rugged B-29 Superfortress, and the gun fit was changed to three Berezin B-20 autocannons, each with 160 rounds of 20mm ammunition. Two were in the nose cowling firing with interrupter gears, and the third fired through the hollow drive shaft. The gunsight was a simple WWII model and there were no pylons for bombs.
(The belt-fed B-20 fired the 20x99mm Soviet cartridge at 800rpm.)
There were no electronics other than a radio and the design was intended for daylight, clear-weather operations only. The cockpit was laid out in as simple of a manner as possible.
(The original design sketch for the plane’s cockpit.)
The VRDK concept was not altogether new in the Soviet Union. In 1941, Professor Genrikh Abramovich wrote a scientific thesis on the use of this set-up as an alternative to dangerous rocket engines or unreliable jets. The Soviet defense leadership allowed Abramovich to establish his own small engine bureau to refine the concept.
(Abramovich proposed grotesquely modifying the in-service Yak-9 to accept a VRDK, to get his concept into WWII as quickly as possible. This was never done.)
Other countries had been studying powerplants similar (but not identical) to the VRDK’s operation during WWII. In Italy, the Caproni company built a demonstrator plane called the CC.2.
This plane had a L.121 piston engine which (unlike the MiG-13) did nothing but power a compressor, which forced air at high velocity through the fuselage. At the exhaust end, a heated metal ring ignited fuel injected directly onto it (effectively, a crude afterburner) adding more thrust. While the system worked, it was not applicable to any usable military warplane and the concept went nowhere.
On the other side of the world, Japan developed a powerplant called the Tsu-11. It was intended to power the Model 22, a successor to the MXY7 Okha suicide rocket-plane. The problem with the Ohka was that it was powered by a bundle of single-use solid-fuel rockets. These produced rapid acceleration down onto the target ship, but also had extremely short (about 20 NM) range, meaning the tote plane (usually a lumbering G4M “Betty” bomber) had to close dangerously near a target fleet before releasing the kamikaze on it’s one-way trip. By the summer of 1945, the US Navy had learned to defeat Ohkas by shooting down tote planes en route before they could drop the kamikaze vehicle. For the Japanese, this was a double loss, as not only was the kamikaze pilot’s life wasted, but the “Betty” and it’s flight crew were lost as well.
(A surrendered Model 22 examined by the US Army in 1945. This would have been the successor to the infamous Ohka. This photo shows the side-mounted air inlets and Tsu-11 exhaust.)
The Tsu-11 is more closer to a classical motorjet, and probably the nearest powerplant to the Soviet’s VRDK. Compared to a regular Ohka, the Model 22 had the rocket packs replaced by a small inline gasoline engine. No cooling system was necessary as engine lifespan was obviously not a big concern for kamikazes. This breathed through bifurcated air intakes on the fuselage, which also fed a compressor attached to the engine. As there was no propeller, 100% of the engine’s output went to compression, which was surprisingly strong. Into the chamber behind the compressor, fuel was sprayed and ignited, the combustion thus producing thrust.
(Tsu-11 on a test stand.)
During the post-WWII occupation, it was concluded that about four dozen Model 22s had been built, probably as many if not a few more Tsu-11 engines. None were ever used. Japanese personnel told occupation troops that the Tsu-11 engine was also intended to be used on trainers for what would have been the Imperial military’s first jet fighters, as by mid-1945 Japan was running out of aviation gasoline and this system consumed less than a true jet. Three Tsu-11s were captured intact after Japan’s surrender and one was taken to the USA for exploitation. As the USA was already operating numerous true jet engines by then, nothing of value was learned. In 1997, engineers from the Smithsonian evaluated the Tsu-11 and concluded that it would have worked, but the thermal part of the set-up added only minor thrust.
At the start of 1944, the USSR was aware that the Luftwaffe would have the Me-262 jet in squadron service within several weeks. By this point in WWII Stalin already felt confident that Germany would be defeated, and his thoughts were already shifting to his capitalist wartime allies. The Soviets were well aware of the RAF’s Meteor and had at least some knowledge of the American P-59.
(Captured Me-262 fighter evaluated by the Soviets after WWII.)
At the time, non-piston warplane research in the USSR was a muddled mess, with each bureau assigned ad hoc set of requests, some illogical and/or duplicates. Overall the Soviet Union was lagging. The USSR’s first attempt at a jet engine, the Lyulka TR-1, was a flop; rocket engines had all their inherent limitations; and nobody had actually tried the VRDK yet.
(The unsuccessful TR-1 engine.)
On 2 May 1944 the Soviet defense ministry took control of all non-piston engine warplane production, to sort out the mess. All major bureaus were assigned a non-piston engine project; some jets, some rockets, and for two bureaus (Sukhoi and MiG) the VRDK.
Both bureaus received identical requirements: a single-seat fighter, using the VRDK system, with a ceiling no less than 33,000 and a top speed in level flight of 810kmh (503mph or 437 kts). The speed requirement was significant, as to that date no operational Soviet fighter could breach the 800kmh mark. The 1944 requirement specified that each bureau must have two prototypes ready by March 1945.
(The basic project “N” / I-250 design.) (artwork from testpilot.ru website)
During this time, MiG quite fortunately had the services of a young engineer named Gleb Lozino-Lozinsky, picked up from the Tairov design bureau after it’s disbandment. Lozino-Lozinsky had a passion for non-piston engines; ranging from the bizarre (airborne steam plants) to the more practical (jets). He was naturally quite interested in the VRDK. (As a side note, his final project was assisting in the design of Buran, the 1980s Soviet space shuttle.)
On 19 September 1944, blueprints were submitted for final approval. These were actually rejected by the Soviet military, specifically because of the cockpit. The pilot was unprotected and also, was sat so far to the rear that on the runway the nose would completely block his view. MiG added bulletproof glass and an armor-back seat, but as far as the location, there was nothing that could be done. The prototype’s fuselage had already been built and there was no solution short of starting over from scratch.
(Wind tunnel tests of the first I-250.)
Ground tests of the prototype I-250 started in February 1945, by which time Soviet ground forces had already advanced inside of Germany. The prototype I-250 was painted all-over white and nicknamed “White Knight”.
(“White Knight”, still with the original tail skid)
The “White Knight” first flew on 3 March 1945, under piston power alone. On the third test flight several days later, the VRDK was engaged for the first time.
On 23 May 1945 the I-250 “White Knight” achieved a milestone, being clocked at 825kmh (446 kts); the first controlled, level Soviet flight above the 800kmh line. Immediately MiG was given go-ahead to build another ten I-250s, now designated MiG-13. The MiG bureau was ecstatic. Artem Mikoyan presented the test pilot with his own car as a gift; private automobiles were never easy to obtain in the USSR, let alone during WWII.
The joy was short-lived. On it’s 26th test flight, the “White Knight” was exploring use of the VRDK at low altitudes. At 800′, as the plane passed over ground observers, the horizontal tail started fluttering violently, until it disintegrated. The plane tumbled out of control. The pilot attempted to bail out but was too close to the ground and killed.
The accident’s cause was determined to be insufficient strength of the tail structure. The second prototype, already under construction, was modified with a new tail and taller rudder. The tail skid was replaced with a tailwheel which retracted into a fin-like housing that also added more inflight stability. The second prototype was painted in sea blue and nicknamed “Blue Stocking”.
(“Blue Stocking” with the taller rudder, tailwheel, and other changes.)
“Blue Stocking” first flew on 20 July 1945 and itself almost crashed on it’s maiden takeoff. Immediately after leaving the runway, the pilot felt a loss of response on the controls. Only with great skill did he manage to turn around and safely land. The issue was later identified as a blueprint error on the revised tail structure and rectified. Thereafter there were few problems. The I-250 was popular with MiG’s pilots, considered agile, simple, and very fast.
A total of 432 test flights were made by the Soviet military. Despite the optimism of MiG’s pilots, their military counterparts had a lesser outlook on the I-250. To nobody’s surprise, pilot visibility on the ground was atrocious due to the cockpit being set so far to the rear.
The main item noted was the most obvious: with the VRDK running, the I-250’s performance was phenomenal. But it could only be run for 10 minutes maximum. When shut off, it was dead weight. On the piston engine alone, the top speed was 361 kts. This was less than existing piston-engine WWII types and certainly less than anything the MiG-13 might face in a future war.
During the flight tests, it was determined that the VRDK had a total lifespan of 35 operational hours. The seven injectors in the combustion chamber were called kameryeh (cameras) by mechanics as they operated by a sort of shutter mechanism; and understandably took a pounding in the high-pressure, high-temperature chamber. The 35 operational hours equates to roughly 200 on/off cycles. Replacing the VRDK was a “capital repair” (the job had to be done at a specialized facility) and reading between the lines, it was likely assumed that each plane’s lifespan would end with it’s powerplant’s.
(“Blue Stocking”s air intake was slightly narrower than the original design.) (photo via airwar.ru website)
The Soviets estimated that to train a groundcrew mechanic on the VRDK would take 116 man-hours each; this of course being above and beyond training needed to service engines in general. The USSR’s peacetime conscription period for enlisted groundcrew was only 2 years, so an additional half-month of training time was a notable issue.
The other VRDK plane from the original 1944 Kremlin order was the Sukhoi bureau’s Su-5. It had a wingspan of 27’9″, and was powered by an identical powerplant to the MiG-13. It was armed with one NS-23 autocannon and two UB machine guns.
The Su-5 first flew on 6 April 1945. During tests it fell just a bit short of the mandated 810kmh speed, topping off at 793kmh, or 428 kts. Otherwise in regards to handling, maneuverability, etc it was equal to the MiG-13. One difference was that the documents presented by Sukhoi suggested no more than 3 minutes use of the VDRK (compared to 10 minutes by MiG). It’s unclear why, maybe Sukhoi was just more risk-averse.
On 15 June 1945, the piston portion of the prototype Su-5’s powerplant blew up. It was repaired with a used VK-107, which itself was worn out by October. The second prototype was never flown. With ex-German jets in hand, Soviet interest in the VRDK was waning and there wasn’t justification for wasting two bureau’s time with it. The Su-5 was cancelled.
the end of WWII, MiG at a crossroads, and continuation of the I-250 project
WWII in Europe ended on 8 May 1945. With the German surrender, the USSR’s aerospace industry changed overnight. The country now had access to all of the Luftwaffe’s technology.
(A Heinkel He-162 test-flown by the USSR after WWII. The Soviets were more interested in the BMW engine than the whole Volksjäger itself.)
(Summary of German jet planes and engines captured in 1945.)
At a fairly heated and acrimonious meeting in Moscow, leaders of the WWII OKBs decided against directly copying entire German fighters; however all agreed to exploit and copy the technology within, especially jet engines.
(By early 1945 the MiG-1 was gone completely, while the MiG-3 was out of production and relegated to rear-area defensive use only.)
(The I-225 failed to achieve a production order and was cancelled altogether after WWII. This was MiG’s final piston-engined fighter design.)
(The MiG-9 “Fargo” would not fly until April 1946 and did not fully enter squadron service until 1947.)
In the summer of 1945, the MiG bureau had no fighter in frontline service, no fighter still in production, and no new fighter ready to start production. For an OKB, this was a politically dangerous position.
While other OKBs were tinkering around with German engines, the MiG bureau’s future, at least in the short term, rested on getting some sort of positive resolution to the I-250 project.
(The La-164 was simply a WWII-veteran La-7 with a PVRD-430 ramjet under each wing. It was not a success. All over the world in the mid-1940s, engineers were throwing hail mary’s to try and keep propeller fighters relevant.)
(The Lavochkin bureau’s La-150 was a quick attempt to slap captured Jumo-004 engines into domestic airframes. As one might guess just by looking at this picture, it was not a success.)
continued tests in the Cold War era
On 12 July 1946, “Blue Stocking” suffered an engine fire and had to make an emergency landing. The plane was never repaired.
The I-250’s public unveiling was supposed to have been on 7 November 1946, during a military airshow. The event was cancelled due to poor weather and the design was never again slated for public display, as it’s official future was by then already in doubt.
On 29 November 1946, the Soviet military leadership decided that two jets, the MiG-9 “Fargo” and Yak-15 “Feather”, would be the next generation of Soviet fighters. Just about everything else fighter-related was cancelled; for certain work on all proposed new piston-engined types ended. For the I-250, a lone respite was granted in that it was allowed to remain in a sort of limbo, pending further VRDK trials.
(Unlike a turboprop, there was no real need for the VRDK’s piston portion to be aligned with the compressor’s axis of thrust; additionally there was no reason why the PTO shaft couldn’t be fitted with a differential to power multiple compressors. This high-speed tactical reconnaissance design was proposed late in WWII. It would have used surplus Charomskiy ACh-30 piston engines and new-build VRDKs. By the time it was ready for submission, the frontlines had shrunk so much that the need was redundant.)
MiG’s records show that on 4 December 1946, besides the two WWII prototypes, eight partially-assembled I-250s existed on that date. There are maintenance records for nine serial numbers, so it’s safe to assume the 10 planes ordered in May 1945 were finished.
Beyond this, the total number of MiG-13s ever made is surprisingly, still in 2017, not entirely certain. On 26 February 1946, an additional 50 planes were said to have been requested. This would bring the final total to 62 (including the prototypes), but some notable sources (including the aviation historian Piotr Bukowski) state a total of 50; perhaps indicating that the 10 from 1945 were rolled into the 1946 order, or, that the latter order was never finished.
Finally on the other end, there are people who suggest even the 1945 order was never finished (for certain, two of these were used for ground tests) and the 1946 order was never even started.
to the Soviet navy
In May 1947 the VVS (Frontal Aviation, or the Soviet air force) decided against a production order for the I-250. MiG was determined to bring about some sort of positive conclusion to the project, and repackaged it for use by AV-MF (the Soviet navy’s air wing). It was proposed to use the I-250 as an overwater escort fighter for land-based, twin-engine torpedo bombers. The fuel capacity was increased by 38% but none the less, the design was a questionable choice for this type of mission.
On 19 September 1947, the Soviet navy accepted the I-250 on a probationary basis. In October, at least one of the type was flying out of a naval airfield near Riga. This plane had flown there unassisted, including a stretch with the VRDK running. The test pilot felt it was a decent design worth further study.
On 3 November 1948 the Soviet navy concluded it’s evaluation of the MiG-13, and suffice to say it was not a glowing review. Many of the problems were not fundamental, but rather showed a plane which had been rushed from raw drawings to production line without a lot of time inbetween. The preflight for each plane took 30+ minutes, which would have been unsustainable in war. While quite simple to maintain day-to-day, oddly enough the opposite was true long-term – for example, to replace a leaking fuel tank required complete disassembly of the airplane, including dismounting the wings. Also MiG had no winterization kit to fill fluid systems with an inert gas; this would present a challenge in the Soviet arctic.
No full operational history of the MiG-13 in the Soviet navy has ever been released; if any even survives to the present time. There is significant doubt as to whether the Soviet navy actually put them to use at all. In 1949, when the type was finally fully obsoleted, there were four replacement VRDK units still unclaimed at the factory – which had received zero spare parts requisitions in the meantime. Considering the 35-hour rated lifespan of the powerplant, this might seem odd if they had been in normal use.
All of the 1946-ordered planes went to the navy. Besides the aforementioned increase in range, the radiator design was altered as the ones on the prototypes failed constantly. Some were delivered with a revised gun fit of four 20mm autocannons, two to a side in the nose, all firing via interrupter gears.
As a side note, of all the Soviet navy paperwork that survives, the designation MiG-13 was never used. Instead it is called “MiG – VRDK”, “MiG-3 (sic) with Special Engine” and so on.
There is no record of which specific AV-MF unit flew the type. A good guess is the 9th Red Banner Guards “Kirkenesskiy” Regiment, which during the late 1940s flew the Il-4 “Bob” torpedo bomber (a WWII type) along with a few Hampden HP.52s left over from British Lend-Lease during the war.
(The Il-4 “Bob” continued in Soviet navy use after WWII.)
Beginning in 1945 this regiment received DB-7 “Box” bombers; the Lend-Lease version of the A-20 Havoc. After WWII, Stalin had no intention of returning these to the USA. These planes supplemented and eventually replaced the “Bob”s until themselves being replaced by Tu-14 “Bosun” jets in 1952. During this seven-year span, the MiG-13 would have been an ideal match for the “Box”; all the more so as the regiment was already flying essentially a non-standard type. This regiment was based at Severomorsk-1 naval airbase near Murmansk in the arctic.
A different possibility is the 51st Red Banner Mine & Torpedo Regiment. During WWII this unit defended Leningrad during the siege. After WWII, it took over the former Luftwaffe airbase of Groβ Dirschkeim in East Prussia, which had been annexed to the USSR as the Kaliningrad exclave.
(Douglas DB-7 “Box” of the 51st Red Banner regiment at Donskoye in the late 1940s, with WWII decorations still on the plane.)
(The Soviets renamed the Groβ Dirschkeim airbase Donskoye. This WWII Luftwaffe hangar remained in use into the 1990s.)
The 51st Regiment flew the “Box” until 1948 when it briefly operated the WWII-era Tu-2 “Bat” before switching to jets in 1952. For a little over a year in 1948-1949, this airbase also operated the MiG-9 “Fargo” jet fighter; so if there was a spot where the MiG-13 might have been a useful “middle” between piston engines and jets, this unit seems ideal in this timeframe.
Finally, it’s possible that due to the small number built, no squadron actually had formal custody of them.
end of the road
From January through March 1948, only six MiG-13 training missions were flown, for a total of 2½ hours in the air. By this time, the Yak-15 “Feather” and MiG-9 “Fargo” fighters were already in full service, as was the Yak-17UTI “Magnet” trainer; and it was clear that the age of the jet had indeed fully arrived. On 3 April 1948, the MiG-13 was withdrawn from active service, and in 1949 the aircraft and all spare parts were discarded. None is known to survive.
obscurity in the west
Besides the unique VRDK, another interesting aspect of the MiG-13 was how it, apparently, completely escaped notice by NATO intelligence. NATO never assigned a reporting code name, and the US Air Force never assigned a type number. The plane does not appear in any recognition guide of the era, all now long since declassified.
Of the three so-called “missing MiG numbers” (fighters always received odd numbers, other types even), MiG-5 would have went to project “DIS” (a twin-engine fighter cancelled during WWII), MiG-7 would have went to the I-220 or I-225 (both cancelled at the end of WWII), and finally MiG-13 to this plane. The Soviets never revealed why the postwar MiG-9 “Fargo” jet was leapfrogged in sequence by the WWII MiG-13. NATO intelligence was at least aware of the “DIS”, and probably had some knowledge of the I-220, so it might be reasonable that they would have investigated what the final missing number was, but that doesn’t appear to be the case.
Beyond the usual heavy Soviet secrecy of Stalin’s era, little was done to safeguard knowledge of the VRDK. The MiG bureau’s in-house newspaper, Istrebitel, ran an article on the “N” project. Istrebitel was obviously not for public consumption but was not a controlled document either. Decades later, in 1981, a Soviet book titled Kryl’ya Rodiny made mention of the I-250 project but apparently went unnoticed by aviation historians in the west.
(artwork by Julian Malejko)
As far as the USSR’s Cold War allies, supposedly during a 1950s Warsaw Pact exercise of the Soviet and Polish navies, the MiG-13 was mentioned in passing by a Soviet officer in that it had been used for self-defense of it’s own airfield and was already out of service. When the two Germanys reunited in 1990, the Luftwaffe found nothing in the defunct East German military’s records indicating they knew of the plane.
Whatever it’s level of actual service after WWII, the MiG-13 and the VRDK were a dead end. As far as the plane itself, the era of propeller fighters was over. As for the VRDK, it was born fully mature – that is to say, no matter what tweaks and improvements might be added, it was not going to get better, it was already at the peak of it’s technology from the start.
Nothing else ever became of the VRDK. Today, the I-250 is only really notable for it’s uniqueness and it’s obscurity.