1:72 Helwan Aircraft HA-410

1:72 Helwan Aircraft HA-410 “4642” Egyptian Air Force (EAF); 204th Fighter-Bomber Brigade, Belbaits Airfield, around 1971 (Whif/Kit bashing)

1:72 Helwan Aircraft HA-410

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

Some background:
The Helwan Aircraft HA-410 (Arabic: حلوان ٤‎٠٠‎) was an indigenous supersonic jet fighter aircraft developed in Egypt during the late 1960s. Its design took place in the wake of the less successful lightweight HA-300 interceptor, designed by famous German aircraft engineer Willy Messerschmitt. Like its smaller stable mate, the HA-410 was an ambitious project for Egypt, at the time seeking to expand both its aerial civilian and defence industry.

Compared to the HA-300, the HA-400, how the project was initially called, was a much bigger aircraft, comparable to the North American F-100 ‘Super Sabre’ and similar in operational and political respects to the Indian Hindustan Industries ‘Marut’ fighter. The aircraft was planned as a home-grown alternative to the Soviet Su-7 fighter bomber, which had been acquired by the Egyptian Air Force (EAF; Arabic: القوات الجوية المصرية‎, Al-Qūwāt al-Gawwīyä al-Miṣrīyä) and employed in the Six Day War in 1967. This event uncovered certain deficiencies of the type, like the Su-7’s relatively poor ordnance load and range, as well as its high landing speed.

Under the influence of the ensuing War of Attrition with Israel, the HA-400 prototype was designed around the same Lyulka AL-7 turbojet engine as the Su-7, inheriting its power but also the poor reliability – even though the engine’s high resilience against FOD, sand and dust was a vital aspect for the EAF.

The HA-400’s design was conventional, with a barrel-shaped (non-area-ruled) fuselage, reminiscent of the US-American North American F-100 Super Sabre or the French Dassault Super Mystère B2. But the HA-400 incorporated different features like a translating centerbody, a movable cone in the air intake for managing airflow to the engine at supersonic speeds. It also featured clipped delta mid-wings with a 60° sweep, not unlike those of the MiG-21 and a one-piece, all-moving tailplane.

The main landing gear retracted inwards, partly into the lower fuselage, the twin-wheeled front landing gear retracted forward. The landing gear was rigid and suitable for operations on semi-prepared airfields. The pilot sat in a pressurized cockpit, offering better for- and downward vision than the Su-7.
The Armament comprised two 30mm cannons in the lower forward fuselage, plus sevem ordnance hardpoints for a total external weapon load of about 3 tons.

The first prototype flew on August 6th 1968, two additional airframes followed. The EAF’s operational evaluation from November 1968 to December 1996 found the new fighter to have superior performance but declared it not ready for wide-scale deployment due to various deficiencies. These findings were subsequently confirmed during operational suitability tests. Particularly troubling was the poor directional instability in certain regimes of flight. The aircraft could develop a sudden yaw and roll which would happen too fast for the pilot to correct and would eventually overstress the aircraft structure to disintegration. As a remedy, the fin was enlarged and a ventral fin for better longitudinal stability added. Another critical point was field performance: the initially pure delta-winged HA-400 showed poor take-off and landing characteristics, offering almost no improvement in comparison with the Su-7.

Helwan Aircraft investigated a new wing design with extended wingtips for an increased wing area and boundary layer control. The result was a new "cranked" wing, with wingtips at a shallower sweep of only 45° just outboard of the wing fence. The new wing also featured a boundary-layer control (BLC, "blown flaps") system, with engine air bleed blown over the flaps to keep them effective at lower speeds. These improvements made takeoffs and landings less ‘hot’ and intimidating. Unfortunately, the Lyulka AL-7F-1 didn’t provide enough bleed air to make the BLC system very effective, but the new wing alone improved slow speed flying characteristics enough to justify its use. An additional brake parachute, housed in a fairing at the fin’s base, reduced landing distance even further.

Under the lingering tense atmosphere with Israel, serial production of the modified aircraft, which had been re-designated HA-410 by November 1969, started in early 1970. Soon the new aircraft saw their baptism in fire in 1973 during the Yom Kippur War. Success was limited, though, due to teething troubles with the hydraulic and BLC system, general engine unreliability and the lack of a powerful radar which would allow true all-weather/night attack capability – the HA-410 only featured a RP-21 ‘Sapfir’ radar system, the same as used in export versions of the MiG-21. Consequently, the HA-410 was almost exclusively used in the daylight ground attack role, even though some machines were, equipped with up to four IR-guided K-13 AAMs, used for point defence around air bases. EAF HA-410 were later also actively deployed in the Egyptian-Libyan War, a border skirmish in July 1977.

A total of 75 aircraft were built, including 13 two-seated trainers, equipping three EAF squadrons, made exclusively up from this type. The EAF was the only user of the HA-410. Yugoslavia showed interest in the type in the late 70ies, as well as India, but no plane was ever exported. The HA-410, as an aircraft, proved to be tough and capable, despite its reliability shortcomings and stability problems which called for an alert pilot. No aircraft were ever lost in air-to-air combat. However, twelve were lost due to accidents and technical failures, six were lost to ground fire and three were lost due to friendly AA fire, since the HA-410’s silhouette was easily mistaken for an Israeli Super Mystère B2.

The last examples were withdrawn from service in 1988 and consequently scrapped, being replaced by Su-20/22 and F-16.

General characteristics:
Crew: 1
Length (fuselage only): 50 ft. 8 in (15.48m),
Length incl. pitot: 57 ft 8½ in (17.57 m)
Wingspan: 28 ft 7¼ in (8.71 m)
Wing area: 394 ft² (36.6 m²)
Wing loading: 77.4 lb/ft² (379 kg/m²)
Height: 16 ft 9 in (5.11 m)
Empty weight: 21,000 lb (9,500 kg)
Loaded weight: 28,847 lb (13,085 kg)

1× Lyulka AL-7F-1 turbojet with 66.6 kN (14,980 lbs) of dry thrust of and 94.1 kN (22,150 lbs) with afterburner

Maximum speed: 1.025 mph (895 knots/1.650 km/h/Mach 1.52) at 36,000 ft (11,000 m)
Cruise speed: 570 mph (495 knots/915 km/h)
Service ceiling: 59.000 ft (18.000 m)
Range: 1.580 km (981 miles)
Ferry range: 3.200 km (2.000 mi) with drop tanks
Rate of climb: 31,950 ft/min (162.3 m/s)

2× 30 mm Nudelmann-Richter NR-30 cannons (120 rounds per gun) in the lower front fuselage.
Seven hardpoints (3× under-fuselage, 4× under-wing, outer pair “wet” for drop tanks) for a total of 7,040 lbs (3,190 kg) of ordnance, including drop tanks, unguided missiles, iron bombs, napalm tanks and K-13 AAMs.

The kit and its assembly
If you recognize what’s behind the fictional HA-410, you are well-informed about aircraft history indeed! Believe it or not, this model was derived from a real-life, Cold War era cruise missile! Sick idea? Maybe, but a nice challenge!

The HA-410 is actually a Raduga/OKB MiG Kh-20M (AS-3 “Kangaroo”) nuclear warhead missile, which had been developed from the unsuccessful MiG I-7 jet fighter from the late 50ies. The mighty Kh-20 had exclusively been carried by Tu-95K (“Bear B”) bombers until the late 70ies. The basis for this model is A Model’s 1:72 scale Kh-20M kit, which includes the massive ground handling trolley for this huge weapon – the kit is about 21cm long!

I had hoped that just changing the vertical fin would be enough, but all wing areas are much too small for a plane that actually takes off of the ground by its own power. At first I considered wings from an A-7 and the tail fin of an F-16, but when I recently was given a Su-15 from PM Models from a friend – a rather crude and basic kit – I just found what I needed to create a complete aircraft.

Bashing both kits was an efficient solution, since the Su-15 not only provided wings and stabilizer parts, but also a complete landing gear with wells, as well as a clear canopy that would fit well onto the bare Kh-20M. As a side note, I decided to attribute this plane to Helwan Aircraft as a kind of tribute – calling it a MiG or Suchoj design would have been too obvious, and using Egypt as part of the whif game made the contsruction of the background easier.

But back to the subject: Biggest challenge was to outfit the bulgy missile with anything an operational, manned aircraft would need: a cockpit plus canopy, a complete landing gear including their respective wells, and accessories like weapon hardpoints.

Any such “extras” were collected from the scrap box:
● All tail areas come from the PM Model Su-15
● Wings and lower fuselage also come from the Su-15, but had to be modified (see below)
● Main landing gear struts and wheels were taken 100% from the PM Su-15, too
● The double front wheel was also taken from the Su-15, the well is from an Italeri IAI Kfir
● Cockpit canopy comes from the Su-15
● Cockpit tub is also a part of an Italeri Kfir, with some extensions
● The dashboard comes from a Heller Alpha Jet
● Not certain where the seat comes from, the pilot figure is from a vintage Matchbox kit
● All weapon hardpoints come from the scrap box
● Ordnance is a collection of spare parts:
– Drop tanks come from a KP Su-25 kit
– Bombs are modified Matchbox 1.000 lbs bombs, with clipped fins and an added balistic rings

Lots of work, despite the plane’s rather simple look. Especially the integration of the lower fuselage was a tough job, since it is one piece with the wings. Not only the part’s width had to be trimmed, stability also had to be guaranteed, and fitting this part with a square diameter into the circular Kh-20M’s body was not a simple task! had to fit a basically square part into the round Kh-20 fuselage… But the result looks IMHO good.

Many surface details like air scoops, antennae, the two guns and weapon stations were added, and the Su-15 canopy needed a matching fairing on the Kh-20’s hull, which was built with polystyrene strips.

I settled for an indigenous Egyptian camouflage paint scheme for the HA-410, which is called "Nile" or “Nile Valley”. This scheme has been used by the EAF on various planes like MiG-17 and -21, as well as Su-7, -17/20 and even Tu-16 bombers. With its wavy lines and strong color contrast, "nile Valley" is very unique and attractive, IMHO, and even authentic for the model’s era. There seems to be no defined pattern or even color paradigm, just that sand is involved, a dark contrast color which ranges from dark brown to drak grey, and a demarkation line between these colors which ranges from light green through slate grey to blue-grey. AFAIK, any available paint was used in Egypt, even car paint, so choice of color is a true ‘free for all’.

The basic colours I chose are Humbrol 74 (Linen), 78 (Cockpit Green) and 98 (Chocolate), but that was only the beginning. Some layers of dry painting with lighter shades like Humbrol 103 (Cream), 121 (Light Sand) and 71 (Beige), RLM 02 on the green areas and a mix of 98 and 64 as well as pure 168 (Hemp) on the brown areas, lightened everything up. Lower sides were painted in Humbrol 65, a light blue with a greenish hue, and treated with FS 36320. Overall, the kit received a light black ink wash and a weathering touch with dry-brushed light grey (Humbrol 64) and Hemp (Humbrol 168).

EAF markings come from a vintage Matchbox MiG-21MF (PK-41). The arabic number comes from a Su-24 aftermarket decal sheets. Stencils and warning signs come from the vast OOB decal sheet for the Kh-20M.

Overall, the fictious HA-410 looks either like a fat MiG-21 or a short Su-7, but features details uncommon to both! Very Soviet, but unlike anything that rolled off of Cold War fabrication lines. Really subtle… o.-

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