1:72 Heinkel He 115 D-4b, ‘6I+CK’ of the 2./SAGr 130, Deutsche Seeluftstreitkräfte; Hafrsfjord (Stavanger), Norway, 1944 (Whif/Matchbox kit conversion)

+++ DISCLAIMER +++

Nothing you see here is real, even though the model, the conversion or the presented background story might be based historical facts. BEWARE!

 

 

Some background:

In 1935, the German Reich Air Ministry (RLM, Reichsluftfahrtministerium) produced a requirement for a twin engined general purpose floatplane, suitable for patrol and for anti-shipping strikes with bombs and torpedoes. Proposals were received from Heinkel Flugzeugwerke and from the Blohm & Voss aircraft subsidiary Hamburger Flugzeugbau. On 1 November 1935, orders were placed with Heinkel and Hamburger Flugzeugbau for three prototypes each of their prospective designs, the He 115 and the Ha 140.

 

The first prototype Heinkel flew in August 1937, testing was successful and the He 115 design was selected over the Ha 140 early in 1938, leading to an order for another prototype and 10 pre-production aircraft. The first prototype was used to set a series of international records for floatplanes over 1,000 km (620 mi) and 2,000 km (1,200 mi) closed circuits at a speed of 328 km/h (204 mph).

 

Defensive armament initially consisted of two 7.92 mm (.312 in) MG 15 machine guns, one in the nose and one in the dorsal position. Late He 115s were fitted with a fixed forward-firing 15 mm or 20 mm MG 151 cannon and two fixed, rearward-firing 7.92 mm (.312 in) MG 17 machine guns in the engine nacelles.

As main armament, the early He 115 variants carried LTF 5 or LTF 6b torpedoes and SD 500 500 kg (1,100 lb) or SC 250 250 kg (550 lb) bombs. Some also carried LMB III or LMA mines, and later variants could trade fuel for ordnance, so that their range was extended.

 

At the beginning of the war, the He 115 was used for dropping parachute mines in British waters, normally aiming for narrow passages close to busy ports on the English south coast; the River Thames was also a prime target. Apart from its use as a minelayer and torpedo bomber, the He 115 was used for coastal reconnaissance and by KG 200 to drop agents behind enemy lines.

 

However, the He 115’s slow speed and relatively light defensive armament remained a constant weakness, and in order to eradicate this flaw, Heinkel proposed in 1939 a new variant with a crew of four (instead of three), considerably more powerful BMW 801 radial engines and an additional weapon station in a ventral position behind the bomb bay.

 

An initial prototype, called He 115 D-0 and fitted with BMW 801C engines rated at 1,147 kW (1,560 PS) each, was produced in 1940 and successfully field-tested. Especially the new engines made a considerably change: the He 115 D’s top speed rose from a ponderous 327 km/h (203 mph) of the early variants with BMW 132K 9-cylinder radial engines to more than 400 km/h (248) in level flight, and other performance figures were improved. Nevertheless, the additional weapon station did not find approval – it turned out to be obsolete, because instead of more, heavier weapons with a longer range and a higher weight of fire were needed. Additionally, the accommodation for a fourth crew member added much dead weight to the aircraft, so that the whole proposal was regarded as ineffective ans subsequently deleted.

 

However, in this refined form, the upgraded machine was accepted by the RLM in 1940. He 115 production was not resumed, though, but rather turned into an upgrade program for the fleet of in-service aircraft (He 115 B and C in various sub-versions), leading to a variety of He 115 D variants.

 

The He 115 D upgrade primarily consisted of engine upgrades, now with BMW 801A engines. For defense, the He 115 D's rear gunner/radio operator became armed with two 13 mm (.51 in) MG 131 machine guns, which replaced his former light MG 17 machine gun as well as the optional fixed machine guns in the rear of the engine fairings, which had proven themselves to be highly ineffective, once enemy pilots had become aware of them. Since the He 115’s narrow body precluded any powered turret on the upper or lower fuselage, the defensive armament was moved to the flanks: Each of the heavy machine guns was fitted into half-teardrop-shaped Ferngerichtete Drehringseitenlafette FDSL 131/1B turrets and mounted on each side of the aircraft. This unusual installation was remote-controlled from the gunner's position in the rear of the glazed cockpit area with a sophisticated gun-aiming setup, and could cover a wide section of the aircraft’s rear hemisphere – even under it, which was a major improvement.

 

The unit was controlled through a pivoting handgun-style grip, trigger and gunsight at its center, to aim the guns vertically - with both turrets elevating and depressing together when operated - and horizontally, in pivoting each gun separately, outward away from the fuselage side when aimed to one side or the other. Aiming was facilitated through a bifurcated telescopic sight that allowed almost free sight above and below the fuselage in almost any rearward-facing direction. The guns were electrically moved and fired, and an electrical contact breaker acted as a form of "interrupter", as used on many forms of multi-engined, turret-armed WW II aircraft, preventing the gunner from shooting off the He 115’s tail plane.

Another armament improvement for all He 115 D variants consisted of the replacement of the light, nose-mounted MG 17 machine gun with a heavier MG 131. The fixed MG 151/20 cannon under the nose, carried in a fairing in front of the bomb bay, was retained or retrofitted to all D conversions.

 

Several variants were introduced: The D-1 was the initial, standardized torpedo bomber and mine layer, while the D-2 had reinforced floats and special equipment for operation from ice or snow. The D-3 was a dedicated mine layer. For this special role these machines received enlarged bomb bay doors, so that two parachute-droppable sea mines could be carried instead of just one, exploiting the type’s improved ordnance capacity of 2.000 kg (4.400 lb).

The D-4 variant was a specifically modified version for anti-shipping operations. Some were direct conversions, but many D-1s and D-2s were upgraded to this standard, too, all receiving the new designation.

For its special role, the He 115 D-4 variant was outfitted as a carrier aircraft for the guided Henschel Hs 293 glide bomb and the Hs 294 glide torpedo. Due to its weight and size, only a single Hs 294 could be carried externally under the fuselage, and it was rarely deployed since the weapon’s weight and drag drastically affected the He 115’s handling. The weapon’s deployment was also hazardous, due to the struts under the He 115’s fuselage. The Hs 293 saw more frequent (and successful) use. Theoretically, two Hs 293 bombs could be carried on pylons under each of the reinforced outer wings (which could carry up to 1.000 kg (2.200 lb) each), but, typically, only a single Hs 293 was carried under the starboard wing and a drop tank as counterweight and range compensation for the extra drag under the port wing. Furthermore, the He 115 D-4 was outfitted with either the FuG 203 “Kehl” radio guidance and control transmitter system and a steering console at the bomb aimer’s station, who visually guided the bomb to its target through a simple joystick, or, alternatively, the FuG 203 with its draggy antenna array was replaced by the more reliable FuG 207 “Dortmund” wire guidance system (incl. a spool with 18 km /11 ml of 0.3mm wire attached to the weapon pylon). The respective machines were differentiated by an “a” and “b” suffix.

The final variant that entered service was the D-5, a fast, long-range reconnaissance aircraft. It featured a reduced armor and armament, but carried additional fuel tanks and camera equipment.

 

Field modifications and other upgrades were also common: Some machines received a manually operated MG 151/20 machine cannon in the nose weapon station instead of the standard MG 131 for a better defense of the front sector, and some machines were upgraded with a MK 103 30 mm machine cannon in a more voluminous fairing under the bomb aimer’s station.

A few D-1 and D-4 machines were also experimentally outfitted with a 37 mm (1.46 in) Bordkanone 3,7 (a.k.a. BK 3,7) with 28 rounds and even a 50mm (1.96 in) MK 214 machine cannon with 22 rounds in a drum magazine in this position – primarily against ship targets, but also against slow Allied patrol bombers, which could be attack out of their defensive weapons’ range.

 

In total, about 100 He 115 B and Cs were upgraded to the D standard, which was finished by late 1943. The aircraft had its finest moment on anti-shipping operations against Arctic convoys from bases in northern Norway. Because the first convoys lacked air cover, the slow and lightly armed He 115 was less vulnerable than near the English coast. With the appearance of carriers and escort carriers, coupled with new Soviet heavy fighters like the Petlyakov Pe-3bis, Luftwaffe air superiority over the convoys was challenged and losses increased. The remaining He 115 B and Cs were consequently taken out of front line service in 1944 (but still served in search and rescue duties or in covert operations), but some of the He 115 D, esp. the more sophisticated D-4 and D-5 versions, soldiered on until 1945.

 

 

General characteristics:

Crew: 3 (pilot, bomb aimer, radio operator/rear gunner)

Length: 17.30 m (56 ft 9 in)

Wingspan: 22.28 m (73 ft 1 in)

Height: 6.60 m (21 ft 7.75 in)

Wing area: 87.5 m² (942 ft²)

Empty weight: 6,150 kg (13,564 lb)

Loaded weight: 12,200 kg (26,872 lb)

 

Powerplant:

2x BMW 801A 14-cylinder radial engine, 1,560 PS (1,539 hp, 1,147 kW) each

 

Performance:

Maximum speed: 403 km/h (250 mph)

Cruising speed: 365 km/h (227 mph)

Combat radius: 2,100 km (1,305 mi)

Service ceiling: 7,400 m (24,240 ft)

Wing loading: 139.4 kg/m² (28.2 lb/ft²)

Power/mass: 188 W/kg (0.116 hp/lb)

 

Armament:

1× fixed 20 mm (.787 in) MG 151/20 machine cannon under the front fuselage

1× flexible 13mm (.51 in) MG 131 machine gun in nose position

2× remote-controlled 13 mm (.51 in) MG 131 in FDSL 131/1B barbettes on the flanks

A total internal and external ordnance load of 2.000 kg (4.400 lb),

including up to 5× 250 kg (550 lb) bombs, or two such bombs and one torpedo of 800 kg (1,800 lb),

or one 920 kg (2,030 lb) sea mine in the Internal bomb bay.

A single Hs 294 guided glide torpedo, carried externally under the fuselage.

Alternatively, two underwing hardpoints could carry loads of up to 1.000 kg each, including iron bombs

and drop tanks (up to 900 l), Hs 293 guided glide bombs and unguided LT10 “Friedensengel” or LT 11

“Schneewittchen“ glide torpedoes.

 

 

The kit and its assembly:

A project I had on the agenda for a long time, even collecting donor parts and kits, but never had the drive to tackle it. But the “Amphibian” GB at whatifmodelers.com in late 2017 gave the impulse to finally build a model of the semi-fictional upgrade of the rather overlooked He 115 floatplane.

The whole thing is not purely fictional, since the BMW 801-powered He 115 D actually existed – but only as a single prototype. However, I wondered if some more upgrades would have been possible, and this led to this model.

 

The basic kit is Matchbox’ venerable He 115 B/C – a simple affair, but the He 115 is, to be honest, a simple aircraft, slender and big. In my case, it’s a Revell re-boxing, and the dark green styrene, in which it is moulded, turned out to be rather brittle, not making it a truly pleasant build (unlike the light grey styrene Revell frequently uses for the Matchbox re-issues, which is somewhat smoother).

 

As the only IP alternative there’s just the FROG mould (and, beware, it comes in a Revell re-boxing, too!), but I am not certain if it is anything good at all? The Matchbox kit appears to be a bit more modern, even though it is very, well, simple, and basically goes together well. But it needs attention at every seam, and the nose section is tricky to mount, too.

 

The model was built mostly OOB, but received some superficial mods and enhancements:

 

The BMW 801 engine transplants come from an Italeri Do 217 K-1, including the propellers and the engine mounts/adapters. The problem: the diameter of the 14-cylinder engines is markedly smaller than the original 9-cylinder radials, so that the “adapters” had to be used to bridge this difference. But even with this help, some serious sanding and PSR were necessary. Additionally, the BMW 801s are longer than the original engines, and the adapters push them forward even a little more. Thanks to the aircraft’s sheer size, this change of proportions is not too obvious.

 

The FDSL 131 barbettes were taken from an Italeri/Bilek Me 210 kit, which has been earmarked for a conversion (without them). In order to mount the weapon stations, holes were drilled into the He 115’s flanks and, internally, a construction to hold them in place, made from styrene strips, was added. The periscopic sights above and below the fuselage were scratched from round styrene strips. As a side effect, the original hole in the canopy for the manual machine gun was elegantly covered.

 

Under the nose, a fairing for the machine cannon was scratched – it consists of sections from an F-14 recce pod. The MK 103’s barrel was scratched from styrene, with an improvised muzzle brake. The manually operated MG 17 in the nose was replaced by a heavy MG 151/20.

 

The Hs 293 comes from a Revell He 177 A-6, together with its pylon. Just a small fairing (a modified 1:144 F-16 centerline drop tank) was added as a container for the wire spool. The drop tank on the other side is a find from the scrap box (IIRC, it belongs to an ART Model F8F Bearcat), modified with fins to (vaguely) resemble the Luftwaffe’s 900 l drop tanks for the Do 217 (which carried the Hs 293 in a similar fashion).

Under the floats I added scratched ice skids, a suitable upgrade for an aircraft operated in Norway and over the Northern Atlantic.

 

Inside of the cockpit, a few details were added like a floor for the bomb aimer figure, and some internal structures added (all scratched from cardboard, and styrene strips and bits), plus a rack for the bomb aimer from an Italeri He 111, IIRC. Not much effort was put into this area of the model, since the kit would have its canopies closed, and the many braces on the clear parts would preclude any good view, anyway.

 

 

Painting and markings:

Finally a good occasion to apply a scheme that some He 177 bombers, operated over the Atlantic, carried around 1944, consisting of a disruptive pattern of RLM02 greenish grey and (supposedly) dark green RLM 73, with hard edges and a low, hard waterline to light blue undersides.

 

However, based on the illustrations and a few real world He 177 color pics in that scheme, I rather changed the dark green tone to RLM 72, which is rather a dull, dark greyish olive drab than the bluish RLM 73. The undersides became Lichtblau, RLM 76 – another deliberate choice instead of the typical, brighter RLM 65 for sea-borne aircraft. The upper camouflage was taken around the wings’ leading edges and onto the floats.

The paints come from the different sources: for the RLM 02, I used Revell’s acrylic 45 (which is a tad more olive green and darker than RLM 02), the RLM 72 was approximated with Humbrol 66 (Olive Drab), which IMHO comes very close to the murky German tone. RLM 76 for the undersides comes from the ModelMaster Authentic line.

 

Due to the sheer size and the complex structure of the aircraft with its floats and the many struts, painting took some time. Everything was painted with brushes, freehanded, only for the waterline on the rear fuselage some tape was used.

 

After the basis scheme was settled and dry, the kit received a light black ink wash and some panel post-shading with lighter versions of the basic tones, including “pure” RLM 02 (Humbrol 240).

 

The markings/decals were puzzled together from the scrap box – on the upper surfaces, simplified white crosses with thin outlines were used, almost resulting in a low-viz livery, and the tactical code was created from single letters (TL Modellbau). The “angry penguin” emblem is not really correct, but I thought that it would be a suitable mascot for the aircraft and its theatre of operations.

 

After that the model received some weathering with dry-brushed light grey on the leading edges and walkway areas. Exhaust soot behind the engines was created with grinded graphite and also some dry-brushing with light grey, simulating burnt areas due to lean fuel mixtures. On the floats I also added a waterline – a frequent sign of wear on the He 115 when it would stay aground/afloat for some time, with a mix of greens and greys.

 

The interior became RLM 66 (Dark Grey, used Humbrol 67, which is supposed to be that tone), as a typical late-war color instead of the earlier RLM 02 in which the He 115 was originally delivered. Both Hs 293 and the drop tank were painted in RLM 65 (Humbrol 65), as a subtle color contrast to the otherwise rather subdued aircraft.

 

 

A relatively subtle conversion, of a rather overlooked (and actually pretty boring) aircraft. Looks more interesting now, I think, and everything that went into the conversion was picked from real life and mixed up for something new.

The longer, slender BMW 801 engines make the aircraft IMHO look more elegant and purposeful, and the barbettes, as well as the bigger guns in general, are a suitable upgrade, too. The Hs 293 might be a little over the top, but for a slightly futuristic Luft ‘46 touch it’s just the ticket – and from an ordnance load perspective it’s even plausible. And, finally, the special paint scheme (which is real, too) just underlines the modernization of the venerable aircraft type for the late 1944 era.

 

Done