By me
All photos me too, copyrighted
Even though summer is in full swing – with matching weather to boot – the airshow season in Croatia has nevertheless been uncharacteristically subdued of late. While there still are many small local shows around, large events are few and far in between, with even some long-standing and popular gatherings failing to make an appearance in 2016. The hopes of the nation had therefore been invested in this year’s Croatian International Airshow Varaždin (CIAV), which had – listing everything from ultralights to multiple combat jets – promised to be one of the country’s biggest and most exciting shows of the decade.
While the full guest list had indeed made for a mouth-watering read, the attendees that had caught my eye the most were (naturally!) rare lighties from the East, including the L-200 Morava (one of which had previously been featured here), Europe’s sole airworthy Aero Ae-145, a rare Yak-11, an even rarer Soko J-20 Kraguj counter-insurgency piston single – as well as two Soko G-2 Galeb jet trainers.
Unfortunately though, various issues beyond the organizers’ control had eventually whittled the list down considerably, with my anticipated oldies being particularly hard hit. The Morava and Aero had been unable to attend due to other commitments and a bit of unfavorable weather enroute from the Czech Republic, while one G-2 and the J-20 had to throw in the towel when mechanical problems prevented them leaving their bases in Serbia. This had only left the other G-2 and Yak-11, the latter of which had quickly become the main target of my visit. While not the first of its type for my camera, the attending example was nevertheless the first one I could get close up to – allowing me an opportunity to put together enough material for a short (but interesting) photo report… 🙂
Taking a creative shortcut across the grass while returning to its parking position following a fine display. With visibility over the nose being virtually non-existent, the Yak-11 (in common with many taildraggers) has to constantly weave from side to side during taxi to allow the pilot to see where the aircraft is going. Since the -11 has a non-steerable tailwheel, all steering is done through differential braking, which can be a cumbersome and tiring experience – making it easier to simply taxi in a wide arc wherever possible.
The Moose Is Loose
A design that is not really easy on the eye, the Yak-11 can trace its roots back to 1944 and the exploits of the diminutive – but superlative – Yak-3 fighter. A lightweight development of Alexander Yakovlev’s first military design – the Yak-1 – the -3 had gained an enviable reputation for crisp, precise and forgiving handling, as well as low altitude maneuverability that few (if any) contemporary fighters could match. The main key to its success was its low weight and high power, with its 1,300 HP Klimov VK-105 V12 having to pull just 2,700 kg all-up – which makes for roughly one horse per every two kilos of loaded mass*.
* however, as impressive as it is, this figure only tells half the story. Among the Yak-3’s European short-range interceptor contemporaries, the Spitfire XIV – still regarded as one of the best of the Griffon-powered Spits – could boast 2,200 HP spread over 3,810 kg, giving an even more astounding 1.7 kg/HP; however, this numerical advantage was – in terms of outright maneuverability – somewhat blunted by an extra ton in mass, giving the Yak a slight edge especially in the dense air at lower altitudes.
Interestingly, the -3’s main rival, the Bf.109G, was almost equal on paper, with 3,400 kg and 1,455 HP for 2.3 kg/HP. But, like the Spitfire, its added bulk did not help its case – nor did the type’s characteristic high wing loading, which made it an inferior performer in the type of prolonged low-altitude turning fight in which the Yak-3 excelled.
Unsurprisingly, its successful record in duels with the Luftwaffe had pretty quickly led to attempts of increasing its kinetic performance even further, in the hope it could even take on the Me-262 with relative ease. Unfortunately, the only suitably powerful Vee engines available at the time were the problematic VK-107 and 108, both of which were pushing the limits of the Union’s development capabilities – and suffering from frequent overheating, failures and fires as a consequence. In an effort to get around this problem, Yakovlev had decided to swap the existing VK-105 for a tried-and-tested radial engine, hoping its simplicity, availability and greater power – not to mention a shorter time-to-service – would offset the increased drag and redesign effort necessary**.
** going radial on a Vee engine airframe was not really a new idea per se. The UK in particular had undertaken several similar efforts during the war – though for different reasons – most notably on the Avro Lancaster bomber in 1941 (creating the Bristol Hercules-powered Lancaster B.II) and the Hawker Tempest fighter in 1943 (taking the form of the Tempest F.II with a Bristol Centaurus unit).
The engine that was chosen in the end was the 1,850 HP Shvetsov ASh-82FN 14 cylinder twin-row unit, at the time one of the USSR’s most common large radials – and, interestingly, also a thorough development of the equally famous Wright R-1820 Cyclone. The installation of a shorter, but heavier engine had also required a tweak of the wing, which had gained a small increase in span and was moved slightly forward to compensate for the new mass distribution.
So equipped, the first (and only) prototype would begin flight testing in early May 1945, quickly demonstrating a 34 km/h / 17 knot increase in speed, as well as markedly improved climb and high-altitude performance – all due to the extra torque generated by the two additional cylinders and 6 liters / 366 cu in more cubic capacity.
However, while this modification was becoming all it was hoped to be, it had arrived too late to make any impact on the war. By the time the prototype had taken off for its first flight – 29 April 1945 – most of Berlin was already in Soviet hands, and the Luftwaffe had long ago ceased to be a functioning force. And while history would show that piston fighters could and would remain in service well into the 50s, the promise of the jet engine had instantly hammered a major nail into the coffin of the radial Yak-3 as a front-line fighter.
Fortunately though, the development effort had not gone to waste. At the time, the vast majority of Soviet flight training was performed on the Polikarpov Po-2 biplane, which – while a sterling design in itself – could in no possible way prepare students for the rigors and requirements of the modern combat-proven high-performance fighter. While there were various two-seat training modifications of such machines available already in 1944 (such as the Yak-9B and La-7UTI), they were few and far in between – and since they took away from the combat strength of the units involved in the actual fighting, only a handful of flight schools could ever get their hands on them.
What was needed here was a relatively modern aircraft, low wing, with a closed canopy, retractable landing gear, flaps, constant speed propeller and all the goodies (and most of the weaponry) that could be found on actual in-service aircraft. It also had to be able to adequately teach students about high-performance flight – while still remaining docile and predictable enough to stop them killing themselves. And lastly, it needed a robust and simple engine that would be more tolerant to student misuse than the sophisticated V12s of front-line machines.
Ticking pretty much all of the boxes, the radial Yak-3 had promised to be a natural for this role. All that was needed to turn it into a trainer was the addition of a second cockpit for the instructor – and swapping the too powerful ASh-82 for the seven cylinder 700 HP ASh-21 (itself essentially a single-row version of the former) whirling a VISH-IIIB-15 or VISH-IIIB-20 two-blade constant speed prop. Flying for the first time in 1946, the new aircraft would soon be given the designation Yak-11, becoming known as Moose in NATO parlance.
In flight testing, the -11 had soon proved that its Yak-3 DNA still ran strong, with the only major design criticisms being levied at the low power available. While 700 HP may sound like a lot for a two-seater, it still had to haul 2,400 kg of mass, making for a chunky 3.4 kg/HP. Even though this was actually slightly better than on similar trainers elsewhere – the T-6 Texan, for example, commanding 600 HP for 2,550 kg of mass – it had nevertheless meant that the Yak-11 was quite sluggish in the climb, and had quickly become known for its lengthy take-off roll. One particular problem, often mentioned, was that during a go around in full landing configuration, the aircraft would barely climb – while a reduction in flap angle in an attempt to clean up the airframe would produce an alarming drop in altitude until the speed built up (once in level flight however, its Yak-3 legacy had meant it was one of the faster trainers out there). Some reports also mentioned a lack of longitudinal stability in production aircraft as compared to the prototype; this – and the lack of power – had meant that the -11 often flew without its full fuel load, with 150 kg being the standard versus the 270 it was actually able to carry.
There were other issues as well; in common with many Soviet light aircraft built in the years following WW 2, the production quality of the Yak-11 had left a lot to be desired. A major source of bother were the effects of long-term exposure to the elements, with wood and fabric components – and particularly the paint – requiring constant intensive care and frequent replacement. Reports also mention cracks in the fuselage structure and control surface mountings – as well as leaking fuel tanks – but most of these problems would eventually be resolved with various production line fixes and general improvements in build quality.
Despite these issues, the Yak-11 would quickly become the mainstay of the USSR’s post-war training fleet – arguably not just because of its handling qualities, but because it was the only suitable and proven aircraft available at short notice and in quantity. By the time production had ended in 1956, 3859 examples had been made, 3152 at the No. 272 and No. 292 Aviation Plants at Leningrad and Saratov respectively – and 707, under the designation C-11, at the Let works in Kunovice, Czechoslovakia between 1953 and 1956.
A mint C-11 taxis in following its performance at a rainy 2007 Kecskemet Airshow. Externally indistinguishable from the regular Yak-11, the C-11 had only differed in minor on-board equipment specifications and replacement of some wooden parts with metal.
Regardless of their factory of origin, all Yak-11s had shared the same flight characteristics, and could be employed in a number of different training scenarios, including intermediate flight, gunnery and reconnaissance training. While its on board equipment would vary considerably throughout its production run, the Yak-11’s armament options had pretty much stayed the same, consisting of a single Berezin UBS 12.7 mm synchronized machine gun firing through the propeller arc (swapped in 1955 for an Afanasyev A-type gun of the same caliber at the request of Czechoslovakia) and two hardpoints for 50 kg of bombs located just outboard of the main landing gear.
Unsurprisingly, its capabilities, production numbers – and the fact that it had the market mostly to itself – had meant that the -11 had found widespread use even outside the Warsaw Pact. Thus, examples could be found even in Albania, Algeria, Angola, China, Egypt, Iraq, Mongolia, North Korea, Somalia, Syria, Vietnam and Yemen. However, the most interesting operator was – hands down – Austria, which had between 1956 and 1965 flown four C-11s (and four Yak-18s) left behind – still in their crates! – by the withdrawing Soviet forces in 1955.
4C-AF of the Austrian Air Force at Zeltweg (Airliners.net)
4C-AH of the Austrian Air Force at Graz (Airliners.net)
Egyptian Holiday
Our particular example can, however, also boast an interesting story 🙂 . Part of a batch of 40 or so Yak-11s intended for Egypt during the early 50s arms buildup, D-FJII was completed in 1952 – likely at the No. 272 works in Leningrad – sporting the serial Y-5434***.
*** some online sources state that all examples delivered to the Egyptian AF were in fact C-11s; however, D-FJII’s current owners state it had been manufactured in Russia one year prior to the start of Czechoslovak production. Additionally, while quoted in all the sources I found, the serial is at odds with those of most other Yak-11s/C-11s, which come in a seven-digit numeral-only format. The reason for this difference is unknown.
However, the tense political and military situation prevailing in Egypt at the time – exacerbated by the 1948 Arab-Israeli War, and later even more so by the Suez Crisis – meant that finding accurate, unbiased and uncensored information about military aircraft dispositions was near impossible, making D-FJII’s history in Egyptian service very hard to trace. Various incomplete production lists suggest that the ordered aircraft may have been delivered in several batches – which would, on account of its production year, make D-FJII part of the first. Other bits and pieces of information suggest that it had likely been based at Bilbeis Air Base in the Nile Delta – the location of the Egyptian AF’s main flight academy even today – remaining in service for less than a decade before the entire fleet was withdrawn from use in 1970.
What is known for certain is that in 1982, aviation restorer Alain Capel had discovered the hulks of 41 examples stored – in a pretty appalling state – at an Egyptian AF dump at Al Akhaa Air Base****. Over the course of the following year, Raymond Capel, as well as Jacques Bourret and Jean Salis of the famous aircraft collection Amicale Jean Baptiste Salis, had managed to persuade the Egyptian government to allow them to buy the entire batch, eventually transporting the lot by container ship to the French port of Marseille in 1985.
**** many sources state that the aircraft had been interred at the “El Aakha” Air Base. However, no such place actually exists; the name is likely a transmutation – through numerous rewrites – of Al Akhaa, a real place with a real air base located almost within spitting distance of the Yaks’ former home of Bilbeis.
Arriving soon afterwards at the mecca of French historical aviation – the airfield of La Ferté-Alais (LFFQ) near Paris – many of the aircraft would be taken under the wing of a dedicated restoration team, who had been tasked with the painstaking process of sorting through the entire mess, hand-picking good parts, reconditioning what could be saved and cannibalizing what could not. Nearly a decade of their perseverance would eventually pay off – and pay off in full – since the dozen or so examples to come out of the process nowadays represent the vast majority of the world’s remaining airworthy Yak-11s/C-11s 🙂 (some having even been converted to single-seat models resembling the original radial Yak-3 prototype).
Borderline
What would become D-FJII had, however, followed a slightly different path. Soon after arriving at Le Ferté-Alais, it would be sold to a buyer in Switzerland, being transported – as is – to the border town of Lausanne for restoration by aircraft engine specialist Philipe Joyet. Having been rebuilt and cleaned up to a fault, it would fly for the first time – again – on 8 July 1995, becoming F-AZIO soon afterwards. For the next decade, it would be based at Lons-le-Saunier Airfield (LFGL) on the other side of the Franco-Swiss border, sporting a two-tone gray scheme once carried by the Yak-3s and Yak-9s of the Normadie-Niemen, a highly-decorated squadron of Free French pilots flying with the Soviet Air Force during WW 2.
Reportedly one of only two fully original Yak-3s remaining, 4 is an actual ex-Normadie-Niemen machine nowadays displayed at Le Bourget (LBG/LFPB). The paint scheme is broadly analogous to the one initially worn by D-FJII.
In 2005, it would be sold to Meier Motors of Germany, becoming D-FJII and operating out of Bremgarten Airport (EDTG) near Freiburg – located, you guessed it, just off the French border 😀 . Its stint there would be comparatively short lived though; in a pleasing bit of circularity, it would return to its spiritual home of Le Ferté-Alais in 2011, rejoining the Salis collection while retaining its German reg. Interestingly, in 2012 it would receive its current paint scheme, with the darker gray tone replaced by olive – and the underside repainted cyan from its original light gray (also one of the schemes used on Normadie-Niemen aircraft).
An Egyptian-French-German Russian in Croatia
Meanwhile at CIAV, D-FJII would – sadly – manage to fly only a five minute display due to time constraints… but its ample time on the ground and a very friendly crew had nevertheless allowed me opportunity to peek around and briefly document this charismatic and beautifully ugly machine… 🙂
Even though it is based on one of the smallest fighters of WW2, the Yak-11 is still a sizable machine! With its pronounced nose-up stance – needed to ensure adequate propeller ground clearance in case students became too enthusiastic with the brakes – the -11 is quite hard to clamber up onto, made all the more difficult by D-FJII’s lack of a handy step behind the wing.
A profile only Father Yakovlev could love. Note also the mixed construction: wood for the front fuselage (minus the cowl) and fabric for the rear, both on top of a steel frame. The wing, however, is metal in and out, with only the control surfaces covered in fabric.
A peek into the front cockpit. While they may be unusual by today’s standards, the ergonomics and layout of the panel do have some interesting touches: the dominating artificial horizon intended for easy reading during aerobatics or instrument flight; the engine gauges grouped generally out of view, but tilted upwards toward the pilot; and all system and navigation controls set within reach of the left hand.
Like many Soviet light (and not so light) aircraft, the Yak-11 makes extensive use of pneumatics, as opposed to the hydraulic setup favored in the west. While air systems are hard to accurately meter out and pretty coarse in application, their advantages include a lower system weight, easier replenishment – and, critically, more predictable behavior in the diverse temperature ranges experienced across the Soviet Union. On the Yak-11, the pneumatics are responsible for actuating the flaps, landing gear and brakes – and are fed from two large air bottles located on the left side on the cockpit (one of which is visible above). Both bottles can be opened and closed by rotary valves next to the seat – which, essentially, are analogous to hydraulic on/off switches on western aircraft.
Sources (in alphabetic order):
- Acig.org – Aircraft overview during the Suez Crisis
- Airwar.ru – detailed Yak-11 history (in Russian)
- Austrian Armed Forces – Austrian Yak-11 history
- Godall.com.au – Yak-11 production list (PDF)
- GoTech.at – Austrian Yak-11 history (in German)
- L’Echarpe Blanche – D-FJII basic information (in French)
- Les Casques de Cuir – D-FJII history (in French)
- Meier Motors – Yak-11 history (in German) and D-FJII history (in German)
- Yak UK – Yak-11 flight test
Achtung, Skyhawk! 