A flying adventure to the Czech Republic for a Walter Minor engine overhaul
- Credit: Archant
Having a Walter Minor engine overhauled in its country of birth encourages a visit – and initiates a voyage of engineering discovery | Words & Photos Tim Cooper
In the early eighties, when I was a television journalist, I had a slight misunderstanding with the Soviet authorities. It was a small matter concerning a pair of Red Army prisoners of war held by the Afghan Mujahideen.
The prisoners were sprung from captivity and given political asylum in West London. Perhaps the Russians, who could never take a joke, weren’t fond of Acton, or perhaps they disliked having their soldiers defect; for whatever reason it was made quite plain that T Cooper Esq should stick to his side of the Iron Curtain. Until very recently that is exactly what I did. Then ‘Bewo’ changed things.
Bob Grimstead wrote about our lovely Czech ballerina in these pages in late 2018. She is a 1966 Zlin 326. (I say she but, Madam?the real pilot in the family?hotly disputes this and claims that she is a he).
G-BEWO is an aircraft from a distinguished lineage that dominated aerobatic competition from the mid 50s, when Zlins monopolized the Lockheed trophy, Ladislav Bezac inventing the Lomcevak on the way.
That lasted until 1968 and the last competition of that decade, when Erwin Bläske won that year’s FAI aerobatic championship at Magdeburg in a Zlin 526 for the East Germans. The Cold War resonates through the next pages.
Bewo, though born in 1966, is still youthful in hours, with a little over 700 in her logbook. Her engine (I’m sticking to the distaff), a 160hp Walter Minor 6 III, is of the same vintage and runs perfectly well?other than when starting, but even the sainted Neil Williams had trouble with this, and wrote in considerable detail on the subject.
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However, we had thoughts about using Bewo for some limited commercial work, and understood that she would need an engine that was within calendar time if we wanted to do that.
We investigated what we should do. This is aviation so there are many answers?all contradictory. The safe answer was that if we wanted a pukka, official overhaul we would need the factory to do it; the Walter factory.
The problem?yes this is aviation, so there is always a problem, and this problem seemed insuperable?was that Walter stopped making piston engines in 1964. Production was then transferred to Avia, Walter having being ordered to concentrate on turbine engine production.
Avia then developed Mr Walter’s engine, adding fuel injection and superchargers. Avia?having now been ordered to make turbine engines?moved production to Lom Praha. Oh! The joys of state-run industrial planning.
But?and this being aviation it is compulsory that there must be a ‘but’?nowadays Lom only builds jet engines and maintains helicopters. The company’s piston engine production has more or less stopped, even though on paper and website it still makes reciprocating engines.
And in any case, even if Lom were banging out engines and parts they would be making the much evolved engines, not the 1960s Walter original which is quite different.
Then Boris stepped in. We first met Boris when we lured him from the Czech Republic to sunny Goodwood in 2018 to teach us how to fly Bewo properly (he flew Zlins as did his father, a military pilot). W-Motor was the answer he told us.
It holds the Czech type certificate for Walter engines. W-Motor, he explained, is the only company authorized by the Czech CAA to overhaul Walter engines. “Be careful,” he caveated mournfully, “W-Motor is very slow”.
We hesitated. Bewo could be out of action for months. Boris had a solution: buy a spare engine, he suggested, and overhaul that. Right, we said. He may as well have proposed getting Czech pixies to make a new engine for us. An email arrived from Boris.
‘I have found an engine,’ he wrote?last flown in 1975, with 599 hours total time since new, full documentation and a price of €5,100. We transferred Czech Crowns to Boris without delay.
Why 599 hours from new? Well let’s return to the Cold War days. All flying was state sponsored, civilian and military. The command economy dictated that airframes were to be produced in factory A, engines in factory B, the resulting aeroplanes were to be flown for a designated number of hours at state run flying schools by pilots that had been vetted politically very carefully.
The aeroplanes would be overhauled at purposely short intervals so that this cycling of equipment kept everyone busy. Our new engine, crated and preserved, had fallen through the cracks of the system, remaining dormant somewhere.
We were too polite to ask Boris where he had found the engine. That he had done so, and that we had a bill of sale was quite enough for us.
It occurs to me that while the economic model I have outlined eventually proved pernicious, murderous and unsustainable throughout the Soviet bloc, and indeed the world, it did however produce an entire generation of aerobatic world champions.
Seventeen of these aces, out of the thirty so far, came from the east of the Iron Curtain. It’s interesting to note that France, where the State similarly has a strong interventionist role in aerobatics, has won the world aerobatic team championship on ten out of thirty occasions. I digress.
A year passed. During which there were many emails from Boris, acting now as our agent, concerning the slothfulness of W-Motor (largely unjustified since in this time W-Motor applied for and received two separate EASA STCs for our fifty year old engine, with the installation of modern magnetos, and the use of automotive spark plugs).
Then, finally, the engine was ready, Form 1 signed and dated. As a welcome bonus, a new Service Letter gave the engine a calendar life of fifteen years, and a TBO of 1,400 hours.
We should go and visit our engine, I suggested. Madam agreed. “Fancy a trip to Czech?” we asked our retired diplomatic friends. Elaine had been posted in Prague at the height of the Cold War in the mid-seventies, and had been back just once since the Velvet Revolution that swept out the communists. Yes please, they replied.
We departed a miserable Gatwick on an easyJet flight full with a raucous, weekending stag party. The weather at Prague was only a little less miserable.
I had no preconceptions about Czech, ‘Czechia’, or the Czech Republic, as it variously calls itself. None at all. My only knowledge of that far away place was derived from Bewo herself.
When not flying Bewo, we spend much of our time discovering wonderful gems of Czech engineering. I point something out to Madam, we then show our discovery to Bob?our flying bestie?and we all coo. “Gosh”, we whisper to one another, reverently, while exercising the sliding canopy bumper stop mechanism, “those Czechs are just so competent, they thought through every tiny detail.
A spring loaded rubber bumper. Wow”. The more we learn, the more details we examine, the more our admiration grows. Bewo is not conventionally beautiful, but nor is she ugly. She eschews the flashy and the trivial.
Her form simply follows function, designed with great and serious thought, her manufacture executed with enormous competence. Her siblings were sold around the world by Zlin with complete confidence that their machine was just so.
As James Gilbert wrote about the Zlin 526 in the run up to the aerobatic world championship in 1966: ‘This may be the finest aerobatic plane yet… Many countries are likely to be flying Zlins, from both East and West, since the 1,200 which have been built to date have been sold to more than twenty nations.’ In the end, 1,450 Zlin 26 series aeroplanes were made, and were sold in 37 countries.
I shouldn’t have been surprised then to discover that, to my mind, these were precisely the traits that characterize the country. By the end of our week in Czechia, I find myself musing that the country felt like an enlarged version of Warwickshire, a county I love.
Prague, as we discovered whilst being guided by Mrs. Diplomat?who could now go where once she had been forbidden by the secret police?is like a very large version of Leamington Spa. Lovely solid buildings, but nothing really flashy.
Dignified public edifices built on an appropriate scale. Elegant terraces of solid middle class apartments, something slightly Parisian about them. And a scattering of nearby ancient castles to give provenance, a sense that all of it was built with money made from hard work, from productive farmland and serious industrial enterprise, not from meretricious chicanery and vulgar speculation. Comfortable and competent, and?well, rather serious.
Editor Philip Whiteman, when told of our planned visit, urged us to go to the Technical Museum in Prague. What an excellent suggestion. It is logically curated?mining in the basement, metallurgy on the next floor, transport filling the main hall, horology in a quiet side room, and so on.
I hadn’t realised quite how the Czechs, the tenth most industrialised country in the world between the wars, had confidently developed their aircraft, their cars, and their motorcycles along a path that was of their own, evolutionary devising.
It is interesting to ponder what the Czechs might have done and what paths they might have taken had they not been occupied from 1938 to 1989, first by Nazis and then by Communists.
The occupiers recognised their engineering talents and yoked them mercilessly. Indeed, without the Czech tanks and artillery pieces the Germans could probably not have taken on Western Europe and Russia at the start of WWII.
Our cultural weekend in Prague over, and with Boris our native guide, we make the short journey to Bubovice (LKBU) airport to the south-west of Prague to visit W-Motor and inspect our engine.
I feel a little disheartened when we arrive at the old part of the airfield in a persistent, miserable, cold drizzle; if soi disant ‘travellers’ ran airfields then this would be what you would expect to find: A disintegrating An-2; a well worn Zlin tow plane; a heap of aeroplane entrails piled against a faded, flaked-paint hangar.
All that is missing was an emaciated Rottweiler on a chain. Boris banging on doors, one eventually opened by a tall man, all Slavic suspicion and gloom, and led by him, through a draughty cavernous hangar that has an abandoned air.
I start to feel that our engine is the orphan we came to rescue from some austere convent, and a foreboding fills me as we are led through age-yellowed plastic strip curtains into the engine tear down shop?a row of eviscerated crankcases, their innards all piled upon serried, dusty, castored racks.
Then onward, through another plastic curtain, into the engine building room. Which is warm and bright, and feels just right and oozes plain, no-nonsense engineering competence. And I can breathe again.
Boris introduces us to Vladimir Svoboda, whom we had followed, the chief engineer. Now in from the cold, wet outside, he switches on a cheery smile, dispelling his gloom, and smiles more still when presented with a bottle of Boris’ home distilled, high octane plum brandy.
Back in the days of State planning, W-Motors was where Walter engines were sent for overhaul for world beating aerobatic aces. Nowadays W-Motor struggles to overhaul an engine each month. A surprisingly prodigious output in current, dire circumstances.
The owner, the mysterious Mr Sima, is away on a quest. Zlins were used extensively as trainers throughout the Warsaw Pact, so Mr Sima spends much time hunting down new old stock parts.
A flying club in Bulgaria today, an old military base in Romania tomorrow, a scrap man in Hungary next week. The stock of parts for Walter engines is running down, and is perilously low?though as we will see later, Czech persistence may come to the rescue.
Vladimir proudly shows us our new, turquoise gaudy engine. That he is proud is reassuring?very. There isn’t much to do or say when first meeting one’s new engine. A few questions asked, an examination of new magnetos, new sparking plugs, the neatness of the lock-wiring.
Then simple admiration, and gratitude for the work that has been done suffices. A promise, engine; we will look after you, in return please don’t let us down.
We drive south and east into Moravia, Boris pointing out this and that, Madam intrigued, and Boris delighted when he points out a military runway that is hidden in plain sight?it is the long, wide, straight stretch of motorway on which we are driving?common throughout these former ‘Sovbloc’ lands.
The countryside rolls by. Yes, I confirm, just like Warwickshire. Rich lands these. We overnight chez Boris, visiting the Christmas Market in Brno, drinking mulled wine. All natives here, unlike Prague where we played spot the Czech, grey Russian occupiers having ceded their ground to moneyed tourist hordes.
A dour and disrespectful sense of humour these Moravians. A famous abstract sculpture in the city is known locally as The Fridge Thief, while a small grotesque high up on the Czech cathedral bares its bottom in the direction of the neighbouring German cathedral.
Hearty roasted duck and pickled everything else for supper, and a digestif of Boris’ plum brandy, distilled in the village from our host’s and his parents’ own fruit. How civilised. And how strong! The morning dawns. Colder, drizzlier, and murkier.
Yet our spirits are high. We are off to meet the Guru?Engineer Milan Jancár, the owner of Zlin - Avion in Otrocovice, ten kilometres west of the city of Zlin. Ever since owning Bewo we have heard glowingly of Zlin - Avion. We are pilgrims.
Otrokovice, a medium sized town, is highly industrialised. Gigantic steel pipelines, flowing with who knows what, follow alongside the road, make abrupt U-turns into and out of factories and over railway tracks.
Smoke stacks trailing plumes in the chill breeze, tired old factories being crowded out by new edifices for production and industry. long grass and tarmac runways (LKZL) to our right. When flying here do not crash into that, warns Boris pointing out an enormous chimney a little way from the threshold.
Here we are, that is the Zlin factory, he enthuses, indicating a run-down, unimpressive complex of low buildings. We navigate a maze of service roads and we arrive. A simple sign, Zlin - Avion, outside this hallowed building where life is gently breathed into resting Zlins, and more, as we will see.
I recall Aeneas:
Are we to believe then, father, there are souls
Who rise from here to the sky of the upper world
And re-enter the sluggish drag of the body?
What possesses the poor souls? Why this mad desire
To get back to the light?
We shake hands with Engineer Jancár. A trim, energetic, business-like man. He assesses us with laser blue eyes. A little wary of us, perhaps a hint of suspicion. “I am sorry, I am very busy and have half an hour,” he says. Two hours later we are still talking, guru to his disciples.
We tour his workshops. His people are purposeful and respectful to him. “The spraying room,” he announces. He opens the doors and we are blinded by celestial light in the spotless booth, large enough for a warbird’s wings.
There are no paint splatters?some magic at work here, I think. Then into a large storage hangar, no dust, spotless again, full of objects. I draw in a breath. A Yak-55 ready for wings, a Zlin 50, condemned, its time-life complete, its wings ready for sacrifice, to be tested.
Painful destruction to establish their fatigue, to establish that in the future other Zlin 50s may perhaps live longer than the mandatory 1,000 hours life sentence. Other aerial objects wait here too?one senses they are simply resting before being restored, that once again they may break the surly bonds.
My jaw drops when I see another Zlin 50, gleaming and showroom beautiful, and nearly ready to fly. “I bought it in South Africa”, explains Engineeer Jancár, “it had crashed through a fence. It is my toy” he says, contentedly.
I realise I had seen this very same Zlin 50 at Rand airport in Johannesburg a decade ago, battered and sad and dusty from its thoughtless excursion. I had often thought of it since, saddened at its fate, hoping someone would breathe life into it again. And here it is. Sheer pathos, I know.
Forgive me, but isn’t this entire enterprise all about pathos, the emotional connection with old machines that we somehow know have spirit? If this is the case, then, do not these places, these workshops where old machines are given new life, whether they be spacious and hospital clean, or cramped and overflowing, serve some spiritual function?
Then into the bustling main workshop. Spotless again. A relaxed but focused atmosphere. Acolytes, there are twelve of them, stop for a moment while their master, Milan Jancár, offers a word of advice here, and asks a question there.
At the front of the workshop, resting on leading edges, gear extended, as though anaesthetized, a two seat Yak-11’s wing, its fuselage next to it, being painstakingly restored. More than seven hundred Yaks were made here in Czech at the Skoda works in Kunovice between 1953 and 1957.
A Frenchman bought 41 of them from the Egyptian Air Force, and they now turn up around the world in different guises as Yak-3s and -9s, but all recognisable to the guru by their Czech factory markings secreted here and there. At the back of the workshop a Zlin 142 nearly restored, but awaiting parts, almost unobtainable, for its Lom engine.
My attention is drawn to the centre of the workshop to the naked, stalky fuselage of a Zlin 526. Where there should be a straight six engine there is a flat six?a Lycoming. I ask, and am told that the Zlin - Avion, determined to keep the Zlin fleet airborne, in the face of engine woes, is working its way through EASA certification to allow both six, and four-cylinder Lycomings to be installed.
The big engines for tow planes, the small four cylinder AEIO 360s?just seven kilos heavier than a Lom, and 20hp more powerful?for aerobatics. Engineer Jancár had worked at the Zlin factory for six years, becoming deputy chief of the design office before leaving, frustrated by the lethargy of the old communist management, setting up Zlin - Avion in 1992.
He had been responsible for the factory’s own Z526L American powered iteration of the aircraft, and was now, on his own dollar, finishing this work. When he is successful?for he will be?he will have ensured that future generations will enjoy Zlin 26s.
We arrange a homecoming for Bewo in the spring for her ARC, and take our leave of this extraordinary place.
We drive through more of Warwickshire and wend up a steep river valley to a windswept plain, Wiltshire I think, and arrive at Luhacovice Airfield (no identifier). We have come to meet the man who may just hold the key to the future of Walter and Lom engines.
Eduard Parma and his company had come to my attention a few weeks before this visit when I discovered that EASA had at long last published a Type Certificate Data Sheet (TCDS) for the Walter Minor series of engines, and that from September 2019 Parma-Technik were the TC holders, not W-Motor.
Eduard was very welcoming, and rather curious about our visit. We explained our connection, and the mystery of TCDS holder was unravelled?the owner of W-Motor, Mr Sima, was old and he had sold shares to Eduard who was already established as a builder of the inverted inline four Walter Mikron IIIC engines.
We were then astonished to discover that in addition to overhauling Mikrons, Eduard had started manufacturing new engines. This is exactly the same as someone in UK tooling up and producing brand new Gipsys. Just imagine that.
The Mikron engine is an exact contemporary of the de Havilland Gipsy, designed in the early 1930s, and manufactured again by Aerotechnik Moravska Trebovain in the 1980s.
That company was then bought by Eduard who designed a new cylinder head and hopped up the power to 80hp?not bad for a dry weight of 67.5kg, running on mogas and at a unit cost of €17,000.
Eduard contracts a local foundry to cast magnesium crankcases, another casting cylinder head blanks, and a plethora of suppliers for all of the myriad other parts.
He has a CNC (computer numerical control) machine that is programmed to finish the heads and other components, and does all this from a small, modern works with just a handful of skilled staff. It’s amazing what you can do if you are determined. Being a Czech, with mechanical engineering stamped into your DNA, and being competent and enterprising helps too.
Eduard’s real prize is to take over Lom Praha’s piston engine division. Securing the Walter Minor Type Certificate is part of this process. Should he be successful?and this is not certain?then a secure future for Zlin 26 series planes operating with their proper engines is a distinct possibility.
We think this a great ambition as the in-line six cylinder Walter/Lom engines have a character that is quite different from flat four Lycomings, and the engine is a real part of the Zlin experience.
We wish Engineer Eduard good luck and say goodbye. We head back to Prague once more where it is our absolute delight to rendezvous with young Radim, a mid-twenties Czech Airlines pilot, and his heavenly girlfriend, Kate. We met Radim in Goodwood when we first bought Bewo.
Radim is a mad and keen Zlinster and instructed and towed gliders in 26 series Zlins to build up his hours as a baby pilot. Radim has invited us to fly with him from his home airfield, Praha Letnany (LKLT).
Letnany is located at the end of the metro line, just five and a half miles from the centre of Prague. Remarkably, this grass airfield is less than a mile from Kbely military airfield (LKKB,) home to the Czech air force transport command.
Amazingly, because the Czechs are competent and serious (have I already mentioned this?), vintage Blanik gliders and modern Airbuses fit perfectly happily into their respective circuits without drama. Radim mournfully refuses to fly the Robins recently acquired by his aero-club to replace their old Zlins, so loads us into a Cessna 172 RG. Madam occupies the right seat…
A fabulous late afternoon flight around the southern fringes of Prague follows, we circle castle after castle and follow the dusk-glistening river back to the airfield. We promise to call in at Letnany next year in Bewo.
A quieter easyJet flight whisks us home to Gatwick. We are delighted to have had such a wonderful trip and to have learned so much.
We are planning next year’s Zlin trip to Czech for our new engine. The big question is where will we go with five hours of full-throttle running-in to do?