Photo Report – Life at Lučko, October 2014

By me
All photos me too, copyrighted

Possibly to compensate for its blatant refusal to play ball for most of the summer, the weather here in continental Croatia has been on its best behavior since my previous post, providing us (mostly) with the same clear blue skies, calm air and pleasant temperatures that we’d expected to see in months past :). Fearing that it may all go terribly wrong at any time and without much warning, out fleet at Lučko has been out and about from sunset to sunrise, getting in as much work as possible without bending any rules. Naturally, the same weather had lured me and my camera out as well, allowing me to present another snapshot of Life at Lučko… 🙂

Back home after an extended leave of absence due to a Cessna-mandated corrosion check, the legend of Lučko is back on the flying circuit. Parked – unusually – outside the hangar following its return from Varaždin (LDVA), BKS easily dominates the apron even in the dark…

Hands down one of the most interesting touring motor gliders (TMGs) in the region, the ungainly Vivat is actually based on the classic Let L-13 Blanik all-metal training glider, to which a 65 HP Walter Mikron III engine, side-by-side seating and a tougher, fully retractable landing gear have been added. Normally based at Sinj Airfield (LDSS) near Split, DSI had on this occasion popped into Lučko for some servicing, having suffered persistent issues with the engine starter.

A peek inside DSI’s clean and pleasant interior. Somewhat more complicated than a modern purpose-built TMG, the L-13SE contains almost as many controls as a standard light piston aircraft, including levers for the throttle, choke, elevator trim, airbrakes, wing flaps, cowl flaps and landing gear.

You could be forgiven for thinking that Lučko was having a helicopter theme day today! As well as HAT, HBA and HBB (the latter of which would later fly a short winch test), we’d soon be joined by Agusta-Bell AB.212 9A-HBM, which had – despite the day’s wind and in true Huey fashion – announced its arrival from miles away. Interestingly, the military side of the airfield was deserted for most of the afternoon, without a single Mi-8/171 to be seen (which in itself is quite unusual).

Definitely the most unusual new arrival into our little fleet, the Sova (“owl”) is an intriguing single-seat motor glider, designed and built by Mr. Marijan Ivanček. Among the many interesting details is the propeller – whirled by a two-stroke Rotax – that folds back under the action of a spring when the engine is not running, thus significantly reducing drag during soaring flight without the need to incur the weight penalty of a fully-retractable prop (of note, while the Sova is a glider with an engine, it does not fall into the same category as the Vivat from two photos above. Due to its ability to fly and operate like a “normal aircraft” during powered flight, the L-13SE is classified as a TOURING motor glider; the Sova however lacks that capability, and is thus labelled as an “engine-assisted glider”).

While for the most part the weather was just as fine as described in the introduction, several mornings – Sunday 19 October included – did let the side down. A common problem during autumn and winter (especially after prolonged rainy seasons such as this summer’s), Lučko, Pleso and indeed the whole of southern Zagreb can be blanketed by thick fog that can reduce visibility down to just 50 meters. While they tend to persist for days or even weeks during the winter, in October and early November they frequently disperse around noon, often leaving behind fantastic anticyclonic weather. On this occasion, a 125 meter visibility and 11 degrees Centigrade were replaced by clear blue skies, 23 Centigrade and just a hint of wind – all within one hour.

Once the fog did clear, flight ops had immediately picked up, including a few flights by the diminutive (and rarely seen) HMB – one of only two R-22s in Croatia and the only one still flying. The first series-produced design to come out of the pen of Frank Robinson – a world-renowned tail rotor expert – the R-22 had first flown way back in 1975 and has persisted in production to this day. HMB itself is an early Mariner version, equipped to carry inflatable floats on the skids for over-water operations and sporting an auxiliary 41 liter / 11 USG fuel tank located right behind the pilot. Interestingly, even though it is registered in Croatia and is operated by a Croatian company – Helimax – it is usually based at Ljubljana (LJLJ) in neighboring Slovenia.

Universally popular primarily due to their low acquisition costs and very agreeable operating economics, all R-22s are powered by variants of Lycoming’s O-320 four-pop – essentially the same engine fitted to the standard Cessna 172N. However, to prevent it from overloading the transmission system (and to assist with longevity), on the R-22 the engine has been de-rated from its nominal 160 HP to just 124. Another important modification – always the eyesore – is the forced cooling fan bolted to the rear of the engine, designed to blow cool, fresh air over the engine block and compensate for the lack of ram cooling in flight.