DONE +++ Project "Bombus": a PantherG tribute build (Zlin Z-37A; OK-BOM)

Dizzyfugu · February 21, 2022, 12:27:24 AM

The kit and its assembly:
"Project Bombus" is a spontaneous tribute build, turning a profile drawing of a fictional aircraft into model hardware. This Z-37A is based on artwork created and published by Václav Madĕra here at whatifmodellers.com some weeks ago, a.k.a."PantherG":

Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM" (artwork re-posted here with the artist's kind permission) by Dizzyfugu, on Flickr

I liked the concept from the start, as it interpreted the aircraft's namesake (Čmelák means bumblebee in Czech) in a colorful and IMHO very attractive and even plausible paint scheme for an agricultural aircraft. Since a Z-37A kit has become available through Eduard, I took the inspiration and decided to take the piece of art into hardware.
Eduard's Z-37A is a very nice little model kit. It is rich with detail, a delicate ribbed wing structure, even though it is in some areas IMHO über-engineered. On the other side, I recognize the difficulties to represent certain details on a plastic model. The landing gear with its (separate) mudguards is such a case, as well as the canopy that consists of three clear parts and a separate roof.
Overall fit is very good, only a little PSR was necessary on the hull. The landing gear is really fiddly, as well as the cockpit interior with its jagged dashboard, and the fit of the clear parts turned out to be rather poor, even though I assume that, in the CAD files for the molds, the parts fit perfectly. But reality is just a little different...

The model was built OOB, I just added a pilot figure to the cockpit (an Airfix figure which received a new head without a military pilot helmet and with earphones) and modified the propeller and the engine block (without the Ivchenko engine's characteristic front louvre, an optional kit feature) with a metal axis and a matching short adapter to hold it, so that it can spin freely.

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) - WiP by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) - WiP by Dizzyfugu, on Flickr

Painting and markings:
PantherG's profile gave clear instructions for the bumblebee scheme, just the colors were not defined – even though simple and clear, too. I tried to get close to the drawing and used enamels for painting, primarily Humbrol stuff, with 2 (Emerald Green) above and 48 (Mediterranean Blue) under the wings, 69 (Yellow Gloss) for the fuselage stripes, 33 (Matt Black) for the fuselage and a mix of Revell 301 (Semi-Matt White) and 147 (FS 36495) for the painted wings and the tail surfaces, because I wanted to avoid a pure, bright white and leave some contrast room for later post-shading and dry-brushing.

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) - WiP by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) - WiP by Dizzyfugu, on Flickr

The yellow stripes on cowling and fuselage were painted first and later masked with black decal stripes, avoiding any mess with tape. The bumblebee wings above and below the wings were painted first with the white/grey mix, then "framed" with green and blue, and finally the black edges and veins were added with a black lacquer pen with a 2mm felt tip, using rulers as well as free hand for minute sections. Turned out better than expected.

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) - WiP by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) - WiP by Dizzyfugu, on Flickr

Lacking information, the cockpit was painted in bright Soviet/Russian turquoise and the pilot received a casual outfit with jeans, a white shirt, and a dark vest (see above).

The kit received a light black ink washing to emphasize the fine surface details, esp. on the wings and the tail, and careful dry-brushing was applied to make the hull more plastic, esp. on the black fuselage areas.

The decals were puzzled together to match the benchmark profile drawing. The registration "OK-BOM" was created with single black 3mm letters from TL Modellbau, the Czech flag came from the OOB sheet.
Finally, the model was sealed with a 3:1 mix of matte and a semi-gloss acrylic varnish (Italeri) for a subtle shine that suits a civil aircraft better than a pure military matte finish. Looks pretty stealthy!

The kit has already been finished, waiting for its photo session over some summer/autumn fields in the Little Carpathians.

PR19_Kit · February 21, 2022, 03:44:58 AM

The pilot obviously likes it too, seeing the grin on his face.....

NARSES2 · February 21, 2022, 06:29:02 AM

Looking good Dizzy and as you say it's a nice little kit

Old Wombat · February 21, 2022, 07:21:36 AM

Tophe · February 21, 2022, 10:08:51 AM

I did not know this plane but Wikipedia explains: https://en.wikipedia.org/wiki/Zlin_Z-37_%C4%8Cmel%C3%A1k

Rheged · February 21, 2022, 10:19:59 AM

That is a very nice looking aeroplane. Well done gents.

Wardukw · February 21, 2022, 10:33:04 AM

Its small and ugly and damn cool..Dizzy this is looking very cool

Tophe · February 21, 2022, 08:19:12 PM

This Z-37 inspired me some Mustang derivatives, thanks!

see today"s post at https://www.whatifmodellers.com/index.php?topic=4461.2730

Dizzyfugu · February 21, 2022, 11:05:39 PM

Glad you like it. Photo session finished last evening.

Dizzyfugu · February 22, 2022, 11:04:14 PM

Finally... And it's cute!

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

Some background:
The Zlin Z-37 Čmelák (Czech: "Bumblebee"), also known as LET Z-37, is an agricultural aircraft which was manufactured in Czechoslovakia and mainly used as a crop duster. Design work on the first purpose-designed agricultural aircraft started in Czechoslovakia in 1961, with a cooperation of two manufacturers: Let Kunovice and Moravan (Zlin brand). The first prototype, designated as XZ-37, first flew on 29 March 1963. It was a cantilever low-wing monoplane of tubular metal construction, the wings and stabilizers covered with duralumin and the fuselage and control surfaces made of fabric. It had a fixed undercarriage with a fully castoring tailwheel, locked to the rudders for ground handling. The pilot's cockpit was in front, immediately behind a Soviet-built Ivchenko reciprocating radial engine with 315 hp. A hopper for chemicals was situated behind the cockpit. This arrangement offered the pilot a good view but was potentially dangerous in case of an emergency landing. A mechanic could be seated behind the hopper, facing backwards. There were also spray booms mounted under the wings, and underwing hardpoints could carry additional fuel tanks for ferry flights. Beyond the basic agricultural aircraft there was also a dedicated freight version with open space instead of hopper and spray equipment and a -3 variant with three passenger seats facing rearwards and extensive cabin glazing.

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

The aircraft was produced from 1965 under the designation Z-37. From 1971, the Z-37A was produced, with a strengthened construction and a roll cage for the pilot. It was produced until 1975, but production was resumed again for a short period in 1983-1984. A total of 677 were produced, including 27 Z-37A-2 two-seaters for crew training. In 1981 an upgraded variant, powered by a 691 shp Walter M-601B turboprop engine, flew for the first time, and the resulting Z-37T was produced from 1985 until 1994, with a total of 51 aircraft built.

The main user of the Z-37 was Czechoslovakia (now the Czech Republic and Slovakia), primarily operated by "Slov-Air" (also styled Slov Air or Slovair), a domestic airline which provided services for agriculture, civil engineering, helicopter emergency medical service and industry. The roots of the airline can be traced back to 1924, when the Bata Shoe Company began building an in-house airline for its corporate travel, operating small aircraft or gyrocopters like the Cierva C.30. Following the establishment of communism in Czechoslovakia in 1948, Bata Shoes was nationalized, and the airline was re-organized as "Svitlet".
In 1950, ČSA was established as the state airline of Czechoslovakia and Svitlet was transformed into a ČSA department, now operating under the label "Agrolet". In 1955, Agrolet once more became an independent entity as a utility airline, principally for agricultural flights. It primarily operated out of Prague Ruzyně Airport, but frequently deployed to local and even improvised airfields, using aircraft types like the Fieseler Fi 156 Storch, Polikarpov Po-2 Kukuruznik, Antonov An-2, L-60 Brigadýr, and eventually the purpose-built Z-37 Čmelák, too.

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

Other Z-37 operators were East Germany (GDR) and other Eastern Bloc countries. Many were exported to the Sudan and India and flown there almost non-stop with the hopper used as extra fuel tank. Variants are as far afield as England and the USA. Current use is limited however because of fuel costs, and the Z-37 is today used mainly in Slovakia. Many are used for glider towing, too, having the ability to easily tow two gliders and often transport four gliders in tow for cross country.

General characteristics:
Crew: one (pilot), plus a passenger/ mechanic (optional)
Length: 8.55 m (28 ft 1 in)
Wingspan: 12.22 m (40 ft 1 in)
Height: 2.9 m (9 ft 6 in)
Wing area: 23.8 m² (256 sq ft)
Airfoil: root: NACA 33015; tip: NACA 44012A
Empty weight: 1,043 kg (2,299 lb)
Gross weight: 1,850 kg (4,079 lb)
Max takeoff weight: 1,850 kg (4,079 lb)
Fuel capacity: 125 l (33 US gal; 27 imp gal) in standard left hand center-section tank,
with optional 125 l (33 US gal; 27 imp gal) in right hand center-section
Payload: 650 l (170 US gal; 140 imp gal) or 600 kg (1,300 lb) of chemicals
Provision for two externally carried fuel transport tanks of 125 l (33 US gal; 27 imp gal) each,
for refueling on site.

Powerplant:
1× Avia M462RF 9-cylinder air-cooled supercharged radial piston engine, 235 kW (315 hp)
driving a 2-bladed Avia V 520 constant speed propeller

Performance:
Maximum speed: 210 km/h (130 mph, 110 kn)
Cruise speed: 170 km/h (110 mph, 92 kn) at 1,500 m (4,900 ft)
Operating speed: 120 km/h (75 mph; 65 kn)
Stall speed: 90 km/h (56 mph, 49 kn) flaps up
81 km/h (50 mph; 44 kn) flaps down
Never exceed speed: 270 km/h (170 mph, 150 kn)
Rate of climb: 3.7 m/s (730 ft/min)
Wing loading: 77.7 kg/m2 (15.9 lb/sq ft)
Power/mass: 0.077 hp/lb (0.127 kW/kg)
Minimum ground turning radius: 5.68 m (18.6 ft)
Take-off run: 150 m (490 ft)
Landing run: 122 m (400 ft)

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

A pleasant build, even though the Eduard kit comes with some technical challenges. Adapting the profile drawing to hardware went more smoothly than expected, and the improvised painting on the wings worked better than expected – a colorful result, quite different from the mostly all-yellow real-world Z-37s, and even though it's a fictional design, PantherG's drawing/scheme looks pretty plausible. Thanks a lot for the inspiration, děkuji pěkně!

Tophe · February 22, 2022, 11:10:55 PM

Quote from: Dizzyfugu on February 22, 2022, 11:04:14 PM

1:72 Zlin Z-37A "Čmelák (Bumblebee)"; aircraft "OK-BOM", operated by Slov-Air; Bratislava Airport (Czechoslovakia), 1988 (Whif/Eduard kit) by Dizzyfugu, on Flickr

Wow! The camouflage disappears completely in the background to feature the bee-wing drawing, I think I have never seen such a perfect camo like disappearing in the background! Congratulations, both to the modeller and the Photoshop artist!

Dizzyfugu · February 22, 2022, 11:23:39 PM

Thank you, glad you like it. But I agree: the trick with the bright green wings works better than expected, at least over verdant szeneries. Credits go to PantherG for the pretty profile of this bumble bee.

zenrat · February 23, 2022, 02:08:20 AM

su27rules · February 23, 2022, 02:30:05 AM

PR19_Kit · February 23, 2022, 06:06:59 AM

That looks the BUSINESS Thomas, and it's really great to see one of PantherG's designs come to 'life'.