1:72 DAP Bunyip Mk. IIB, BF-K of RAAF 5 Sq., New Guinea, late '44

zenrat · June 09, 2019, 03:48:51 AM

If it cleared the runway I would have kept the bigger prop. It would enable that well known fighter pilot Lavochkin Dundee to pull a "that's not a propeller..." moment...

Old Wombat · June 09, 2019, 07:49:05 AM

Good grief, he's almost finished!

Why am I surprised?

This is Dizzy we're talking about!

dogsbody · June 09, 2019, 03:20:44 PM

Looking good!

A question, if I may. Is this aircraft to be powered by an American engine or are you going with the Hercules as comes with that cowling?

Chris

Dizzyfugu · June 10, 2019, 03:19:22 AM

It's a Herc. Bigger American engines were not avaliable at the time, ans since the Hercules was already in the RAAF arsenal (Beaufighter), it's a plausible choice. The size is also a good match for the La-7's fuselage.

The big B-24 prop would have been too big - careful tests showed that there would not have been any (sound) clearance during landing and take-off, and the "new" one works fine and looks more balanced.

No big progress since yesterday, just the undersides were painted in light blue-grey. The white tail comes next, then some weathering and the white leading edges on the wings.

Dizzyfugu · June 10, 2019, 11:53:17 PM

Yesterday's plan fulfilled: tail is white, I did some weathering and post-shading to the model, and I appllied the white wing leading edges with decal material. Tricky stunt, but probably simpler than trying to paint the areas. I also attached the 20mm cannons and did some work on the landing gear. Things come together, I think that I might start with the decals today - puzzled together from various sources (e .g. roundels from an RAAF spitfire, medium sea grey code letters from Xtradecal, serial TBD).

Latest pics to follow soon.

Dizzyfugu · June 11, 2019, 09:56:35 AM

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIb - WiP by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIb - WiP by dizzyfugu, on Flickr

...and this is the current status:

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIb - WiP by dizzyfugu, on Flickr

Old Wombat · June 11, 2019, 10:02:57 AM

Sweet!

PR19_Kit · June 11, 2019, 10:44:33 AM

Ooooooh, look at that!

Dizzyfugu · June 11, 2019, 11:29:48 PM

Decals finished, and I did some weathering. Landing gear has been completed now, and I added four British 60 lb missiles under the wings.
I guess that I can add a final coat of matt varnish today, and then there are some details left to complete (wire antenna, position lights, some oil stains).

Dizzyfugu · June 12, 2019, 09:21:26 AM

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/Eduard La-7 kit) - WiP by dizzyfugu, on Flickr

Old Wombat · June 13, 2019, 03:06:35 AM

That's really coming along nicely!

NARSES2 · June 13, 2019, 06:18:27 AM

Quote from: Old Wombat on June 13, 2019, 03:06:35 AM
That's really coming along nicely!

It is that

Dizzyfugu · June 14, 2019, 01:38:18 AM

Build has been finished yesterday and I started the photo sessions with pics on the ground. Flight scenes will probably follow today. With editing, ETA is Sunday for the final post with pics and a background story, too.

Weaver · June 14, 2019, 04:16:26 AM

That really looks the part - nice one!

Dizzyfugu · June 15, 2019, 10:30:44 AM

Here it is, pictures got finished one day earlier than expected:

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

Some background:
The DAP "Bunyip" fighter was an indigenous development as a successor for the successful CA-12 "Boomerang" fighter, which had been designed in late 1941. The main challenge to this ambition was the fact that fighter aircraft had never been manufactured before in Australia, and that the country's aircraft industry was relatively young and only had acquired experience through license production.

The CA-12 proved to be successful, even though it had several weak spots. While the CA-12 was lively at low level, its performance fell away rapidly above altitudes of 15,000 ft (4,600 m), and its maximum speed of 265 knots (490 km/h) was not sufficient to make it an effective counter to Japanese fighters like the Zero and the Japanese Army's Nakajima Ki 43 ("Oscar"). Similarly, the best European fighters were reaching almost 350 knots (650 km/h), and even relatively sluggish contemporary fighters – like the Grumman F4F Wildcat and the Curtiss Kittyhawk Mk I – were substantially faster than the Boomerang.

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

As a consequence, CAC already commenced work upon a new variant which featured performance improvements in terms of speed, climb and ceiling during the CA-12's flight testing phase. Designated CA-14, this aircraft was designed around an order for 145 U.S.-built, 1,700 hp (1,268 kW) Wright Cyclone R-2600 engines or, alternatively, by the even more powerful 1,850 hp (1,380 kW) Pratt & Whitney R-2800. In parallel, a design team around the Australian Department of Aircraft Production (DAP)'s chief engineer Robert Harford at Melbourne was also ordered to produce an independent, competitive design for a potential CA-12 successor with better overall performance characteristics, but using a different engine.

This was an unusual move, since DAP was an Aircraft Construction Branch of the Department of Supply and Development, an entity that had so far been primarily tasked with the license production of the Bristol Beaufort torpedo bomber, but it was per se not a design or engineering center.
However, the DAP team accepted the challenge and produced the DAP "Bunyip" in record time. This aircraft was a compact single seat fighter aircraft, powered by the British Hercules engine, which was already in RAAF use through the Bristol Beaufighter – a lucky move, since CAC's proposal for their upgraded CA-12 turned out to be a dud: the intended R-2800 was not available for export from the USA when serial production would have started, since any R-2800 production was allocated to US companies. Even though the Australian government favored CAC's proposal, the Bunyip was ushered into production after a mere year of development and testing.

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

The Bunyip was an all-metal construction with a low wing and a fully retractable landing gear. While it roughly shared the CA-12's outline, it was a completely new construction and aerodynamically much more refined than the Boomerang. The widespread use of light metal alloys instead of wood resulted in a lighter and stiffer structure, and, together with a much higher surface quality and the more powerful engine, many small innovations resulted in a significant improvement in speed and climb. Standard armament consisted of six 0.5" machine guns in the outer wings, firing outside of the propeller arc, and two underwing hardpoints allowed bombs of up to 250 lb (113 kg) caliber to be carried.

The first production variant, the Bunyip Mk. I, was introduced into service in summer 1943. RAAF 79 squadron began combat trials of the new type in late 1943 in support of the unit's first sweep over Japanese-held territory from Gasmata on New Britain, together with Spitfires and Boomerangs as benchmarks. During this time, the new fighters made 102 individual sorties and claimed 15 aerial victories while losing only four aircraft in combat – a very successful start, even though these initial hot operations revealed several flaws. Another problem was the type's similarity to the Japanese Nakajima Ki-44 fighter – in order to distinguish the RAAF Bunyips, practically all machines soon received prominent, ID markings in the form of white wing leading edges and tails.

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

Four Bunyips of this initial batch were lost to non-combat causes, mostly related to engine problems: Initially, the Hercules had the tendency to overheat in the hot and humid climate, this problem was traced back to an undersized oil cooler. The carburetor intakes in the wing roots caused reliability problems, too, due to dust ingestion, and there were problems with the stabilizers that tended to flutter at high speed, too.

After only forty Mk. I aircraft, production quickly changed to the Bunyip Mk. II, which incorporated several detail improvements like an enlarged oil cooler (which had, due to its size, to be re-located under the cockpit), dust filters, a stiffened landing gear and a reinforced tail structure. This variant also introduced an alternative armament of four 20mm Hispano cannon in the outer wings (called Mk. IIB, while the IIA retained the original machine gun armament) as well as the option to carry up to four unguided 60 lb missiles under its wings instead of bombs, what made the Bunyip a formidable ground attack aircraft. This role eventually became the type's primary role, since, by the time of the Bunyip Mk. II's introduction, the Spitfire had successfully filled the interceptor role and CAC was on the verge of commencing the manufacture of Mustangs under license to meet the sought bomber escort and air superiority roles. There was also an order for 250 of the new P-51H fighters for the RAAF, which was soon changed into a license production agreement at CAC as the Commonwealth CA-21 Mustang Mk. 24.

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

The DAP Bunyip's active career was short and intense, and the aircraft was exclusively operated by the RAAF. In service, the operating units worked closely together with the Royal New Zealand Air Force, undertaking reconnaissance, artillery observation, ground attack, and aerial resupply missions in support of Australian ground troops fighting against the Japanese on Bougainville, New Britain and New Guinea. Until August 1945 a total of 351 Bunyips were produced at DAP's Melbourne factory. After the end of WWII, the type was quickly phased out, though. Only a handful remained in RAAF service as advanced trainers and as ground instruction airframes until 1949.

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

General characteristics:
Crew: 1
Length: 8.6 m (28 ft 3 in)
Wingspan: 9.8 m (32 ft 2 in)
Height: 2.54 m (8 ft 4 in)
Wing area: 17.59 m2 (189.3 sq ft)
Empty weight: 2,638 kg (5,816 lb)
Gross weight: 3,315 kg (7,308 lb)

Powerplant:
1× Hercules XVII 14-cylinder, two-row, air-cooled radial, delivering 1,735 hp (1,294 kW),
driving a 3-bladed Hamilton Standard, 11 ft 7 in (3.53 m) diameter constant-speed fully-feathering propeller

Performance:
Maximum speed: 632 km/h (392 mph)
Cruise speed: 400 km/h (249 mph; 216 kn) at 4,000 m (13,123 ft)
Stall speed: 150 km/h (93 mph; 81 kn)
Range: 765 km (475 miles)
Service ceiling: 11,000 m (36,089 ft)
Rate of climb: 16.7 m/s (3,280 ft/min)
Time to altitude: 5.3 minutes to 5,000 meters (16,404 ft)

Armament:
4× 20 mm (0.787 in) Hispano or CAC cannons with 200 RPG
Two underwing hardpoints for a total ordnance of 500 lb (227 kg),
or four launch rails for unguided 60 lb missiles

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

1:72 Australian Department of Aircraft Production (DAP) "Bunyip" Mk. IIB, aircraft ,,BF-K/A78-158" of the Royal Australian Air Force (RAAF) No. 5 Squadron; Piva Airfield/Torokina on Bougainville (New Guinea), November 1944 (Whif/modified Eduard La-7 kit) by dizzyfugu, on Flickr

Not a complex build, but the time frame of just nine days made this one, also due to the engine surgery, a tough build. Nevertheless, I am quite happy with the result – the La-7/RAAF combo just looks right, like a natural successor to the stubby CAC Boomerang. And many thanks to PantherG/Wenzel for the inspiring profile!