Tag: Mil

By me
All photos me too, copyrighted

It seems to be a rule of nature that every former Yugoslav airbase still in use today has a few hidden gems with which to tempt the photo finger – even among the locals who were used to seeing them on a regular basis. Croatia’s Zagreb (ZAG/LDZA) has its large MiG-21/Mi-24 graveyard; Serbia’s Batajnica (LYBT) has a bewildering mix of Soviet and indigenous combat and transport machinery that cannot be seen anywhere else in the world; while Macedonia’s Skopje (SKP/LWSK) can boast what are likely Europe’s last non-preserved Su-25s – and very definitely its only Israeli-modified Mi-24s. And Bosnia’s Sarajevo? Well, that has a Rajlovac Helicopter Base and one of the rarest series-produced helicopters on the planet – Mil’s diminutive Mi-34.

While at first glance it looks just as “60s Soviet” as nearly everything else in its family tree, the 34 is nevertheless a pretty special little whirlybird – not just for being the last all-new helicopter type launched in the USSR, but also for being Mil’s final clean sheer design until the Mi-38 of the early 2000s. All of this had naturally ticked the lot of my Achtung, Skyhawk! boxes, so I recently decided to give the Bosnian MoD a ring and see if I could pop down to the country’s capital and tour one of Russia’s more charismatic (and least lucky) rotary designs… 🙂

My first Gazelle

As the early 80s dawned, the helicopter industry of the USSR was slowly – but surely – beginning to feel the adverse effects of the Soviet leadership’s single-minded preoccupation with heavy machinery. With 20/20 hindsight, it is not really hard to see why: the exploits of the Mi-24 during the First Afghan War had clearly shown the value of the helicopter gunship, while the stalwart Mi-8 was proving – day in, day out – its ability to reach even the more distant backwoods of the Union. Then there were the impressive Mi-6 and Mi-10 for when you needed to move stuff, and Kamov’s ungainly – but supremely capable – Ka-25 and 27 families to keep the fleets safe from Yankee subs. Everywhere you looked, there was a shiny and mighty medium/heavy helicopter doing its bit to keep the system going and its citizens safe & (somewhat) content.

At the same time, the people who would go on to fly these things were being trained on archaic machinery such as the 50s Mi-1, which – while solid and dependable – were relics of the early days of Soviet helicopter design, and could in no way prepare pilots for the rigors of operating out on the front lines. As was also the case in the fixed-wing sector, learning to fly a helicopter in those days was essentially like stepping out of a Mach 0.1 Po-2 biplane and straight into a Mach 2.0 MiG-21 – with depressingly predictable results.

Having realized at two minutes to midnight that this problem needed to be addressed ASAP, the powers that be eventually ordered Mil to get itself into gear and start developing an all-new multipurpose light helicopter that could be used equally well for training, competition, transport and liaison – as well as potentially exported internationally even outside the traditional Soviet customer base. The definition of this new machine was also influenced by the successes of the Aerospatiale Gazelle and MBB Bo.105, since one of the key requirements was a proper, no-nonsense aerobatic capability – and not just a willingness to be thrown about inherent to most other training helicopters. At the same time, it also had to have a benign and forgiving nature, informative and precise controls – and flight characteristics that would enable students to get the most out of the experience without scaring them half to death.

But, while the Mil works certainly did have the expertise and industrial capability to pull this off and pull it off cleanly, by the point they’d finally gotten round to it, time was no longer on their side. By the mid 80s – when detailed design got under way – the signs of the USSR’s impending collapse were becoming more and more apparent, and the financing pipelines from Moscow more and more constricted. Faced with a tightening purse, the government’s own procrastination and the Soviet aerospace sector’s general R&D inertia, Mil had suddenly found itself under mounting pressure to do the new helicopter as cheaply and cheerfully as possible while still satisfying what is even today a demanding set of specs – and then getting the thing into the air with a minimum of fuss.

The resulting machine – christened the Mi-34 by its makers and Hermit by NATO’s Air Standardization Coordinating Committee – ended up being a pretty conventional affair, from some angles hard to tell apart from the similarly sized MD500. Flying for the first time on 17 November 1986, the Mi-34 would be presented to the world just seven months later at the 1987 Paris Air Show – a rush that says a lot about Mil’s burning desire to grab export orders and bring in fresh cash to finance further development and production. This need was so pressing in fact that Mil would in 1988 actually send one of the two prototypes to the States in the hope of drumming up some interest there – right in Bell’s own back yard and even before the Cold War had fully thawed out. Indeed, some sources report that Mil officials had been hoping for a 1,000 unit production run to start already in 1990 – a number equal to roughly 60% of all Gazelle production and ambitious even by the standards of Western manufacturers. Unsurprisingly given the situation it was born into, the Mi-34 would eventually enter production three years late in 1993, with a “token run” that would peter out at just 2.2% of its initial target…

One turning, zero burning

As it stood at the dawn of the 90s, the basic four-seat Mi-34 did however have some things going for it. Despite being Mil’s smallest helicopter design since the Mi-1, the 34 did manage to punch some way above its weight, sporting an advanced glass-fiber-reinforced rotor system dominated by a very capable four-blade semi-articulated main rotor (actuated mechanically, without powered boost). This setup had allowed for outstanding agility with maneuvers such as loops and rolls, flight at +3/-0.5 G (impressive figures for a helicopter), a yaw rate of 120º per second (head-turning even today), as well as the ability to reach 140 km/h flying backwards – all of which were firsts for any helicopter ever made in the USSR. Aside from its outright dynamic capabilities, the 34 was still a proper Mil – so it was as tough as nails – and its projected price was low enough to offset (at least for a while) most of its aerodynamic or mechanical inefficiencies, as well as its rather crude finish and lack of refinement inside.

But, while all of the bits on the outside were where you’d expect to find them, under the skin things were a bit less straightforward. Alongside its antiquated avionics setup – the eternal Achilles’ heel of all Soviet designs – the 34 was immediately let down by the only engine it had readily available, the 330 HP Vedeneyev (VMP) M14V-12V nine cylinder radial. While a superlative powerplant known in song and story for its bulletproof reliability, the M14* was nevertheless a heavier, thirstier, more maintenance-intensive and far less efficient solution than even the flat six of the 34’s closest rival – the 1991 Robinson R-44 – let alone the mighty turbines of the Gazelle, Bo.105 and JetRanger (which, admittedly, cost up to for times as much as an entire Mi-34: USD 2 mil for the JetRanger’s Allison 250 vs 500,000 – in today’s money – for a complete Hermit). Coupled with a 600 hour Time Between Overhauls (TBO) that fell woefully short of the 1,500-2,000 hour figures seen westwards, these issues seemed set to limit the Mi-34 appeal long before it even flew.

* while very much a 1950s product – an old school, supercharged, carburetted, 10 liter mass of Russian metal – the M14 did have some plus points however… but only in a specific corner of the Mi-34’s envelope. Its lack of refinement and cruising efficiency was more than made up for by its capabilities during aerobatics, delivering high torque, world-renowned durability when being pushed hard, and a lightning-fast throttle response that no turbine before or since could match. Critically, its shape allowed it to be mounted upright in the fuselage, which in turn made it possible to set it right onto the 34’s CG sweet spot. This in particular did wonders for maneuverability, since it all but eliminated the adverse moments experienced when the engine has to be mounted away from the center of lift – as well as reduced stress on the airframe during high G flight by minimizing the engine’s moment arm.

The engineers at Mil were, naturally, well aware of this straight from the outset, so even before test flying of the prototypes had ended in the late 80s they began looking into other – if less easily obtainable – engine options. Their first choice (and the most cost-effective from a design standpoint) was the Lycoming TIO-540-J six cylinder boxer unit, whose turbocharger and fuel injection were good for 360 HP at takeoff. Dubbed the Mi-34L, this model would have brought the Hermit more on par with the later R-44 – but was, sadly, torpedoed before getting off the drawing board by the dissolution of the USSR. And while import of these engines would have been possible even then, the increased costs for the end user – as well as the lack of support infrastructure within the (ex) Union – represented a pretty strong set of nails in the L’s coffin.

Meanwhile, the loss of the first prototype during a test flight on 27 February 1989 – attributed to deficiencies in its rotor system – had forced Mil into a quick-and-dirty redesign, the result of which was the Mi-34S, the type’s first production-standard model. As well as the necessary improvements to the main rotor, the S would also receive a redesigned (and more extensively glazed) nose, as well as avionics and equipment upgrades that made it possible to certify it to Russia’s new AP-27 standard in May 1995. Broadly similar to the FAA’s FAR-27 governing Normal Category Rotorcraft, a fully satisfied AP-27 had soon opened the legal doors to further international certification, worldwide export and widespread commercial use – the stuff of dreams for Mil’s by-then-exasperated sales team.

Back on the engine front, it would take the company’s next attempt – made in 1993 – to show just how desperate the engineering team was to replace (or at least supplement) the big M14. Called the Mi-34VAZ (or Mi-234 in some sources), this model was to be powered by twin rotary/Wankel VAZ-430 engines running on standard automotive gasoline and developing 230 HP each along the way. A modification of the VAZ-4132 unit used in police versions of the Lada Riva and Samara, the 430s gave a significant payload (and noticeable performance) boost – but their low TBO, expensive maintenance and prodigious fuel and oil consumption quickly turned the -34VAZ into just another paper helicopter. A noteworthy tweak intended for this variant was also an all-new carbon fiber rotor head, which would have improved on the (already improved) fully composite setup of the standard S – but there are, however, no indications whether it was ever carried forward onto any future versions.

Their third crack at it – the more down-to-earth Mi-34A – would be made just two years later in 1995, and had, at the time, promised to finally unleash the full potential of the design by switching to turbine power. However, since there were no indigenous engines of sufficiently low a power and small enough a size available, the A would be based on the same 450 HP Allison 250-C20R as the JetRanger III, fed now from an enlarged 340 liter fuel tank (up from the standard 176) necessary to cater for the turbine’s higher thirst. Sporting an upmarket interior now aimed more at Russia’s growing upper class than traditional flight schools, the A would never make it beyond the mock-up stage, having ended up as another casualty of Russia’s very fragile post-Union financials (not to mention the increasing influx of more user-friendly helicopters from the West).

Interestingly, a second turbine attempt would be made more than a decade later in 2008 with the Mi-34S2 Sapsan (later marketed as the Mi-34AS), powered by the 515 HP Turbomeca Arrius 2F** used on Europe’s best-selling EC-135 and A.109 families – as well as Russia’s own Ka-226T (in the form of the Arrius 2G1). Unlike the old Mi-34A, the S2 had come into being during a much milder economic climate, so it had even made it to the flying prototype stage before nosediving into the dirt. While it had shown a lot of promise as a cheap high-performance utility machine (with 56% more power – and shedloads more torque – than the basic S), the Sapsan would be shot down by none other than Mil’s parent company Russian Helicopters, which had in the early 2010s partnered with AgustaWestland for work on a brand new – and much improved – design of the two-ton class.

** some sources state that Mil had also planned to offer the S2/AS with the option of the Ukrainian Ivchenko-Progress AI-450 unit developing 465 HP – a move that would have likely made the Mi-34 hugely appealing on the (very large) CIS market. However, recent… “political developments” down there mean that this idea is very firmly in toilet for the foreseeable future.

Of further interest, the AI-450 was developed during the mid 90s (’94 onwards to be exact) to power the original Ka-226 – and was in fact the first small, relatively modern gas turbine designed in the former USSR. The only other “baby turboprop” fielded anywhere in the ex-Eastern Bloc was Czechoslovakia’s Walter M601 of the mid 70s – which was never considered for the Mi-34, since even its lowest 710 HP output far exceeded all of the Hermit’s needs.

With the turbine 34 now down for the count, the only way to salvage the time and effort invested was to keep beavering away at the piston model. Mil’s first (stillborn) attempt at it was the Mi-34SM, a simple upgrade of the basic S that would have seen its M14V-12V replaced by the 380 HP M14V-26V, fitted now with fuel and oil systems for inverted flight and boasting a TBO increase to nearly 2,500 hours. The rising popularity of the R-44 in Russia – and the SM’s predicted inferiority in many respects – had however soon forced Mil to shelve this idea and concentrate instead on the much-improved Mi-34S1, powered by the far more potent 365 HP VMP M9FV***. The new powerplant also came packaged with a redesigned main rotor and an all-new gearbox, both of which had proved to be recurring problem areas on the standard S (despite their 1989 post-crash rework).

The S1 would also become the first Mi-34 to feature hydraulically operated flight controls (with the actuating systems supplied by Goodrich of the USA), since the non-boosted controls of the classic S had shown themselves to be pretty tiring during prolonged aerobatics or long-range flight. The list of new features would also include a revised internal structure to prolong service life, and would be topped off by an avionics upgrade that had even included some digital avionics – though it is not clear from available sources whether the setup would be indigenous or sourced from the West.

*** the first significant update of the M14 since its introduction, the M9F was designed by the Voronezh Mechanical Plant (VMP) – the people who actually built the M14 – and was intended to power the stillborn Su-49 primary trainer. A development of the bog-standard Su-29, the 49 would have used hydraulics for actuating the landing gear rather than the traditional Soviet pneumatic setup, the result of which was the addition of a hydraulic pump to the back of the engine case. Other smaller upgrades had included a redesign supercharger for a bit of extra power, three powerful magnetos for better ignition – and in fixed-wing uses (such as on the few Su-26M3s actually made) new propeller mounts to accommodate the German-made MTV-3 and -9 units instead of the standard V-530 shipped with the M14. Interestingly, the Su-49 design had stipulated a power requirement of around 450 HP, which was be achieved by switching to fuel injection, creating the M9FS. However, no Russian-made fuel injection system had been available then, forcing the idea to be scrapped – since the 49’s primary customer, the Russian Air Force, wanted to keep things in-country as much as possible.

Of further interest, the V suffix appended to both the M14 and M9 is short for “vertolet” – or helicopter in Russian – and indicates models adapted to rotary use in which there is no gearbox integral to the engine (as on the fixed-wing versions), but where power is sent to the main rotor gearbox directly using a transmission system.

Flying for the first time in prototype form on 4 August 2011, the Mi-34S1 had quickly shown the potential of being a reasonable R-44 alternative within Russia – but, sadly, still fell far short of being its rival everywhere else. The performance figures had once again highlighted the deficiencies of the radial engine, for despite commanding 120 HP more than the R-44 (365 vs 245 at maximum take-off power), the Mi-34 could cruise only 12 km/h faster (220 vs 202) and fly only a tiny bit higher (14,700 ft vs 14,000). At the same time, it was significantly fatter than the Raven (1,150 kg empty vs 683), carried 33% less payload (330 kg vs 450), hovered outside the ground effect at under half the altitude (3,500 ft vs 7,500) – and could fly 100 km less (450 km vs 550) despite being able to carry 60% more fuel (176 l vs 111). The fuel flow figures too were not that great, with figures of 18-19 GPH being reported in the cruise – noticeably higher than the 15-16 of the R-44.

And then there was its family curse. Right at about that time, the Russian Air Force had decided to pass up the Su-49 in favor of the less complicated Yak-152, which would have retained the traditional M14 and pneumatic installation of its predecessor, the Yak-52. This had, at a stroke, made the M9F redundant, leading VMP to rehash its production plans and abandon the design in favor of further tweaking the M14. The Mi-34 had thus, once again, been left up the creek and without an engine.

As the Mil works scrambled once more towards the West in search of a replacement engine, the 34’s fortunes continued to turn for the worse, since its continual delays, the inability to enter any form of meaningful series production and a lack of international certification (despite the promise of the AP-27) began to wear quite thin with potential customers – both civilian and military. Though UTAir (one of Russia’s largest helicopter operators) and Omsk Aviation Training (one of its bigger helicopter schools) placed orders for 10 each in the early 2010s, the decisive blow would once again come from the Russian AF, which had – having grown tired with waiting for the “domestic solution” to be ready – awarded its highly coveted 100-strong training helicopter contract to Eurocopter and its turbine AS.350 single and AS.355 twin.

The results were inevitable: by 2012, the development of the S1 – and with it practically the whole Mi-34 line – would be suspended indefinitely after just two flying prototypes had been completed. The total tally for the entire Hermit family would thus come to a stop at just 25 – the three original prototypes and 22 production examples…

The Mils Down in Africa

The 34’s constant engine woes and resulting failure to break into the marketplace had inevitably forced Mil to keep tinkering with the design (whatever its powerplant) in the hope of one day finally striking some gold. To this end, a number of specialist versions had been pitched from Day 1****, the only one to enter service being the Mi-34P of 1994. A dedicated aerial surveillance and monitoring variant for the Moscow Police (reportedly only two or three of which were made), the P was developed from the original Mi-34, and was fitted with dual controls, spotlight, IR camera and a riot-control speaker system mounted under the rear fuselage; interestingly, some sources report that the latter was actually of little use, since the roar of the M14 tended to drown out most of what was being said…

Another version that had almost made it big was the Mi-34UT, a different, S-based dual control variant pitched to the Russian AF for its first 100-strong training helicopter tender in 2001. Like the unnamed S1-based model that had sealed the Hermit’s fate, the UT would also come up short compared to the competition – in this instance Kazan Helicopter’s Ansat turbine single, designed by the very factory that produced most of Mil’s transport helicopters.

**** some sources indicate that there may have been other versions under consideration, such as the Mi-44, powered by the OMKB TV-O-100 turboshaft originally developed for the first Ka-226 – and the Mi-34M, a twin-engine six-seat development similar to the AS.355. However, both of these are mentioned only in two places and nowhere else – so given the absence of concrete evidence of their existence, I have excluded them from further consideration.

To add insult to injury, the government’s cold shoulder (twice over) would turn out to be just the tip of an iceberg. Despite its undoubted qualities (especially in the aerobatic role), the 34 would in service suffer from chronic “sovietness”, with a low service life, questionable dispatch reliability and appalling after-sales support that quickly undid any good impressions it made. The largest single operator of the type – the Nigerian Air Force – would be left with a particularly sour taste in its mouth, with all of its nine S models (all delivered from Mil stocks in 2002) suffering rotor gearbox failures soon after passing the 300 hour mark – despite the manufacturer’s claimed 1,500 hour TBO. Being uneconomical to run – let alone repair – the fleet would be permanently grounded and stored after just a few years, their only movement being the 2013 sale of six examples to a private buyer from New Zealand (where five have been reported cannibalized in an attempt to return No. 6 to airworthy state).

From that point on, the bad luck just kept on piling. The aforementioned “lifeline” orders from UTAir and Omsk came to naught due to the downturn of the whole program, while the few other operators who flew them – mostly governmental – began retiring their small fleets soon after due to difficulties in obtaining spares and support. While various production lists are either incomplete or give inconsistent information about the 34’s current and past operators, all point to the fact that Mil’s long-hoped-for sales break westwards ran out of steam already on the Balkans, with three examples sold to Romania and one (featured here) to Bosnia – a total of just four machines shifted in non-Soviet Europe.

All of this had made for a pretty depressing production run: disregarding the three prototypes, just four examples would be completed in 1993, followed by none in 1994, one in 1995, two in 1996, seven in 1997, five in 1998, again none in 1999 and 2000, one in 2001 – and a final two in 2002 when all new production ground to a halt (though some sources state that five more examples were in various stages of assembly, but ultimately never completed). Unfortunately, despite their low numbers, the paucity of records means that it is nigh on impossible to ascertain their current states and how many examples are actually still airworthy…

The Balkan connection

Despite its dismal failure to break into the international market (even within the Soviet sphere of influence), the Mi-34 is actually not really a stranger to the Balkans. Its first contact with the region would come in 1996, when Mil pitched it to the Croatian Air Force – a long-time Mi-8 and 24 user through its origins in the Yugoslav Air Force – which was at the time looking for a training machine with which to equip its newly formed helicopter training squadron. To that end, one Mi-34S was actually sent to the ZTZ maintenance facility adjacent to Zagreb Airport to fly demo flights for the military; but, despite having left a solid impression, the type would stumble here as well, losing out to the more-well-rounded (and better supported) JetRanger III (still in use today).

It was in neighboring Bosnia that the Hermit scored its first – albeit negligible – local success. The sole example that had entered (very limited) service in the training role is, however, mired in some confusion and much mystery – and since I’ve been told that its history is a bit colorful (and not in a good, Achtung, Skyhawk! way), I will leave it be and concentrate instead on its objective nerdy bits 🙂 . Its full serial drags out to 97830001501004, a typical Soviet sausage that – when read properly – say all you need to know about that particular airframe. While there still are some uncertainties in its interpretation, the most plausible version reads as follows:

• 978: the code for the Progress factory in the city of Arseneyev where all Mi-34s were built
• 300: Mil’s internal product code for the Hermit
• 01: produced in the first quarter of the year
• 5: the year being 1995
• 01: part of the first tranche (though it doesn’t elaborate on the scope of the tranche)
• 004: fourth example of the tranche

If correct, this would make it an original (pre-S) model – and only the fifth 34 ever produced (not counting the prototypes). This interpretation appears to be backed up by info I’d received at Rajlovac, stating that this machine is part of the type’s “null series” – in local parlance the name of any post-prototype, pre-series production batch.

What is known for certain is that it had arrived to Bosnia in 1998, becoming VF-3601 soon after. Its history before and during that time remains unknown; indeed, the only Achtung, Skyhawk!-y info that’s fit to be printed is that it was retired with just around 100 hours on the clock – and that it’s M14 is retrofitted with magnetos from the newer M9F, indicating some work had been done on it prior to sale…

Bonus: having posted photos of VF-3601 in several places online, it did not take long for viewers from the region to start sending their materials… such as this video taken at Ćoralići Airfield near the Bosnian town of Cazin:

As always I would like to extend my very sincere thanks to the PR department of the Bosnian Ministry of Defense for its assistance in organizing this visit – and especially all the staff at Rajlovac Helicopter Base in Sarajevo for their hospitality!

Author’s note: the information presented above is the result of my own research into multiple sources (listed below), each of which had presented only part of the Mi-34 story – with possible inaccuracies and urban myths as a result. I have tried, to the best of my abilities, to filter and stitch them into a meaningful and representative whole – but given the type’s small production run and lack of much concrete info from primary sources (such as Mil themselves, who I had contacted without reply), I cannot vouch that this work is the whole truth and nothing but the truth… so if any of my readers have more info – or spot an error – I would be more than happy to hear from them!

Version list:

• Mi-34 (1986): pre-production version
• Mi-34S (∼ 1989): basic series-production version, M14V-12V engine
• Mi-34L (∼ 1991): Mi-34S re-engined with the Lycoming TIO-520-J, not built
• Mi-34VAZ / Mi-234 (1993): Mi-34S with twin VAZ430 rotary engines, not built
• Mi-34P (1994): patrol version for the Moscow Police Department, two or three built
• Mi-34A (1995): reworked Mi-34S with an Allison 250-C20R turboshaft, mockup only
• Mi-34UT (2001): dual-control military training version, not built
• Mi-34S2 / Mi-34AS (2008): upgraded basic Mi-34 with the Turbomeca Arrius 2F or Ivchenko AI-450, not built
• Mi-34SM (∼ 2008): Mi-34S with an uprated M14V-26V engine
• Mi-34S1 (2008): upgraded basic Mi-34 with the M9FV engine

Sources:

• Airliners.net Aircraft Data – Mi-34 entry
• Airwar.ru – Mi-34 production list
• Aviastar.org – Mi-34 entry
• AvionsMilitaires.net – Mi-34 entry (in French)
• Flightglobal archive – Mi-34VAZ entry (PDF)
• Forecast International – Mi-34 data sheet
• Heli Hub – various Mi-34 news articles
• HeliOps magazine – Issue 59 (via Issuu.com)
• Ivchenko-Progress – company history
• Oldwings.nl – Soviet/Russian serial decode (PDF)
• Robinson Helicopter Company – R-44 Raven II specifications
• Ruslet – Mi-34 and Mi-34S entries (in Czech)
• RussianAeros.com – M14 and M9 info
• and various “human sources”