Down Memory Lane - From the Log Books #7

[Guest TOSGcentral]

This gripping episode we will take a look at the Central European factory produced trainers. There are not a lot of types involved so I should get them in a single article. The other countries involved are Czechoslovakia, Romania and Poland.

 

 

All of these were Communist Bloc countries and so the manufacturers had plenty of subsidy and financial support. Russia itself did not do a great deal in gliding production, while initially being apparently very interested in gliding. Russia thus seems to have relied heavily on the Czech Blanik as a mainstream aircraft.

 

 

Significantly, the money input of the Bloc nations allowed for very sophisticated gliders to be manufactured and marketed at a level of design and costs that the West could not readily match for a recreational market.

 

 

The Poles did it much more on their own and produced a far greater range of gliders – more matching the stage by stage evolution of western types for clubs and these aircraft found considerable acceptance this side of what was the Iron Curtain. But on the other hand the Polish gliding industry had long standing traditions and ranks with Germany as one of the world’s leading gliding ‘powers’ and in many aspects was as prolific as the Germans for producing both state of the art machines as well as sensible basic club aircraft and trainers in significant numbers.

 

 

Blanik. I am really going to stir a few people up here because the Blanik as a bit of a ‘sacred cow’ in Australia and I really do not like the bloody things!

 

 

Why is that so? Certainly they are a work of the devil when it comes to airframe maintenance. Sure, they have been around since before I started in gliding and I could not wait to get my hands on one from the regular monthly magazine advertisements. And certainly I was less than entranced by the XXXX-poor airbrakes on the early ones – probably because I had not yet been taught adequate control skills by then.

 

 

I guess that once having put in a couple of hours on a new type I just found them ‘uninteresting’. They were easily mastered, reasonably viceless, did what they were designed to do and mainly did it very well – and were out and out ‘bland’. But over my time in aviation they kept cropping up so I put in a reasonable amount of trips with them for one purpose or another.

 

 

For all my personal taste quirks I have to say that the Blanik was a superb glider and years ahead of its time – First flying in 1956. A high wing, tandem two seater it had a range of systems on it as standard. The stressed metal skin had the expensive flush rivet system to reduce drag.

 

 

The machine had an effective tab driven elevator trim system; a Fowler flap system, semi retractable sprung undercarriage (ie the lower part of the wheel stayed outside so you could land wheels up with no damage); and as double paddle DFS airbrake assembly.

 

 

As mentioned the airbrakes on the early Blaniks where not too clever. They would work perfectly well if the machine was flown correctly in conjunction with the flap system but club training was preaching high speed approaches and that did not fit in either with the flaps or the airbrakes. So the flaps were mainly used to increase wing area for soaring and the airbrakes had their range of movement virtually doubled to fit in with current approach methods.

 

 

The glider took an equally excellent winch or aerotow launch and was not heavy, therefore was a useful club trainer for the less well appointed clubs.

 

 

In common with other high wing tandem trainers the instructor was condemned to the ‘wing root box’ so visibility from the rear seat was not crash hot but actually better than it looked. The little peep holes in the roof gave a good side view above the wing in a turn once you learned how to use them properly. The sprung undercart was great for the instructor!

 

 

A particular feature was that the Blanik is a very strong inherent design. It is capable of doing outside loops when flown solo and flying inverted two up! This is something my wife found out during a rest day at a UK National Championships.

 

 

She was having a mutual flight with an RAF Canberra pilot who looked quite harmless when sipping a beer but was actually his squadron’s most aggressive penetration pilot. Lemmy hammered the Blanik down the main runway, inverted, at 12’ then did a sort of half bunt, half roll, tight turn thing of his own devising to neatly turn around and spot land. He said he liked looking at Kay’s long hair laying in the canopy!

 

 

By 1970 1200 Blaniks had been manufactured and sold in 36 countries. This would have to make the aircraft one of the most prolific and successful gliders ever built in peacetime.

 

 

In Australia, Bill Riley’s SportAvia outfit based at Tocumwal eagerly grasped the ‘Blanik Opportunity’ and sold around 50 of them to Australian clubs and private owners. This would make the machine probably Australia’s most commonly found trainer.

 

 

The Blanik stayed much as it was thoughout production with no great changes. No single seat version was put into production – you flew them two up for training or from the front seat as a ‘single seater’. The type did most of what you asked of it with stalling, spinning and sideslipping being very adequate.

 

 

A motor glider version was made. The first one was a ghastly looking thing that was mainly conventional Blanik and a motor grafted onto the nose. Later a side by side version was produced, also having a mid wing, but achieved little success (in the West anyway) even though it looked less like a bolted together afterthought!

 

 

IS28.

 

 

This Romanian product was very much along the Blanik lines, had the benefit of Communist Block subsidies and thus was another well manufactured all metal two seat glider.

 

 

Like the Blanik it was well finished, a nice sprung undercarriage, much more powerful airbrakes, but the flap system was conventional plain flaps which enabled it to fit in better with the flap trend in single seaters.

 

 

It had a mid wing and nice big blown canopy so visibility was excellent from front or rear seats.

 

 

Of interest to the gliding world in general was that a range of matching gliders were manufactured that gave a basic club fleet. The IS28 would be the main trainer, followed by the IS29 single seater, then the IS28M2 motor glider (an evil thing I will have a great deal to say about in a future instalment) anticipated to be a general purpose back up trainer (paddock landing etc).

 

 

My enduring grizzle with the IS range was the ergonomics. The cockpits were all comfortable enough but the detail design was bloody awful. It seemed that all the systems controls had a different ‘push in to move’, ‘pull out to move’ or ‘twist to move’. This all had to be learnt so that the correct action could be employed instinctively.

 

 

In this area I class the aircraft as a poor trainer unless you flew little else. But for people blowing through clubs on visits or holidays, check flights became more of a challenge for pilot and instructor alike to assess potential competence in the club’s more conventional single seaters.

 

 

One particular feature of note (for myself anyway) was that the IS28 was the most ‘taildragger’ glider that I have flown and instructed on. The single mainwheel assembly was quite tall, even if well sprung and ‘soft’ (which took a lot of the savagery out of the system). But if the glider was not fully held off for landing then it would start bouncing very convincingly – and could take a bit of sorting out.

 

 

Bocian Series. Readers will note that I warm up a bit more here (well it is a personal viewpoint series). I am a very great admirer of Polish gliders and Poles in general. I have had a lot of very good Polish mates as we had an exclusive Polish club at the National Centre and I did a lot of flying with them. They all seemed to have case hardened steel balls and fear was something that someone else had! Their gliders allowed them to indulge themselves!

 

 

The Bocian was the main Polish production trainer and came out along with so many other civilian types in the post war expansion in 1952. It was an all wood, tandem, mid wing gliding trainer and quite big at 18 metres span and about half a tonne at MTOW. They were immensely strong, span with enthusiasm (although predictably) but used a fair bit of height in the process.

 

 

I had one really lovely session in a D model Bocian. I was flying as co-Tutor to the National Coach on a National Instructor Course and we ran out of weather and could not complete everybody. Bill Scull asked me to carry on into the next week and finish the spinning. There was only one applicant left – a little slip of a girl from one of the Lasham clubs and we got on real well together. We had a ball spending an hour turning that Bocian inside out. There was no problem signing her off – she was damn good and kept her cool even when going through the vertical or the aircraft starting to go onto its back.

 

 

This was particularly good because the rear rudder pedals in the Bocian are more flat than upright so the instructor does not have so much mechanical advantage. But the lass handled that all right.

 

 

I had nothing to do with the A, B & C model Bocians (I doubt many, if any, got out of Poland). The Bocian D was the first of them to make significant international penetration and this was followed a couple of years later by the more refined Bocian E.

 

 

I am not sure which of the two I prefer. I liked the D because it was uncompromising. It was a bit of a sled and did not have a sprung undercarriage. The machine was not difficult but did make you fly it – so in my book it was a real good trainer.

 

 

The E was slightly larger (or gave that appearance maybe because it stood a bit higher as the rear cockpit had been lifted a bit to improve the rear seat view even more). The design had been refined a bit and there was a sprung wheel. The type was a tad better on control harmonisation and generally felt more of a precision instrument rather than a tool.

 

 

All of the Bocians have quite steeply sloped sides to the cockpit which can be a nuisance in certain circumstances. It is of no consequence if you have a matched Polish fleet as the follow on to the Bocian was the smaller Mucha which was essentially a single seat Bocian with similar cockpit. A lot of students/pilots unconsciously use the cockpit sides as part of their horizontal organisation. You cannot do that in a Bocian as it always seems to be flying quite nose down, but it was an area we had to watch when transferring people between different types. They tended to fly convential cockpit gliders a bit too fast or the Bocian a bit too slow.

 

 

A little story about Bocians. Derek Piggot got caught in one at Lasham on a routine instructional flight. The Bocian has a two piece canopy. The front bit hinges sideways and the rear portion is on rails and slides back fighter style.

 

 

Derek’s rear canopy became unlatched and slid back faster than he could grab it, broke the rear stops, came off completely and hit the tail. This took about 75% effect out of the elevators.

 

 

A bit of exploration established that although the glider was still under control landing it would be marginal as if the nose dropped they would not get it back and the student was going to be first on the scene of the accident. So Derek ordered him to bale out.

 

 

At this time they were at about 1200’ over the centre of the airfield and everyone on the ground could hear what was going on – especially as Derek raises his voice a bit when he is being emphatic.

 

 

Derek was not having a good morning but it got rapidly worse. The student jettisoned the front canopy and left at speed – arriving safely on the ground shortly afterwards. The front canopy unfortunately did not have a weak link in the restraining strap so the canopy was flailing around on this and sconed Derek – fortunately not knocking him out. At the same time, with the weight gone from the front seat the glider abruptly reared up as the student left, forcing Derek back into his own seat under the G.

 

 

The glider then went onto its back and Derek fell out of it – with enough height left to

 

make an acceptable parachute descent,

 

 

The interesting bit was that the Bocian, now totally empty, stabilized inverted and mooched around for a bit by itself. It then ‘picked a paddock’ and did a most acceptable approach and landing – albeit upside down – totally by itself. Very little damage was done and it was soon flying again. I have a good photo of it in the paddock, surrounded by a totally unconcerned herd of cows quite contentedly munching away!

 

 

Yup – I have a lot of time for Bocians!

 

 

Next time we will take a look at France and a quick trip to designs of other countries that never really made it out of their countries.

 

 

[Guest pelorus32]

Lemmy hammered the Blanik down the main runway, inverted, at 12’ then did a sort of half bunt, half roll, tight turn thing of his own devising to neatly turn around and spot land.

This must have been a bit of a party trick for Blanik aficionados. When I was a young fellow the CFI was an ex-Spitfire pilot and his favourite arrival back at the field was a high speed, low level inverted run followed by a manoeuvre that was basically a wing over that started inverted in the direction of travel and ended upright in the reverse direction and then a landing.

 

Very nice evolution which demanded a great deal more skill than it appeared at first sight.

 

Loving the series Tony.

 

Regards

 

Mike