Vliegmasjien aims to fly C-Wolf amphibian before year-end


Local company Vliegmasjien (Pty) Ltd is planning to fly its locally developed and built amphibious C-Wolf aircraft by 2016, with taxi tests scheduled for December.

Test Pilot Class 1, James O’Connell of Aviation Flight Test Services, who has given input on the aircraft’s systems, will conduct and manage the flight testing. Initial test flying will be 60 hours while a second production prototype would fly 140-200 hours, depending on how much test flying is needed, Vliegmasjien told defenceWeb.

Vliegmasjien has several hangars at Baragwanath airfield and will do all flying from there. The aircraft’s wings are currently at Baragwanath while the fuselage is being completed at Vormbaum Engineering in Johannesburg’s CBD. The prototype manufacturing process began in January 2011, with the maiden flight initially scheduled for 2013.

The first prototype of this South African designed and developed amphibious bush plane (referred to as an integration test rig or ITR) is being hand built but a second aircraft would use production standard moulds and jigs, with the full length fuselage being moulded in two halves for ease of construction. When defenceWeb visited Vormbaum Engineering’s premises, the fuselage was essentially complete, with interior, engine, avionics and systems awaiting installation.

Wolfgang Vormbaum, Vliegmasjien Technical Manager and the designer of the C-Wolf, said that he hopes to install the locally built Adept Airmotive 320T piston engine in August, conduct the first engine runs in September and potentially fly to Oshkosh in the United States next year.

The C-Wolf was first unveiled to the public at the September 2012 edition of the Africa Aerospace and Defence (AAD) exhibition at Air Force Base Waterkloof in Pretoria. Vliegmasjien was planning to exhibit at AAD 2014 but postponed that for 2016 in order to focus on aircraft development.

The C-Wolf was conceptualised by Vormbaum some thirty years ago when he envisaged a rugged bush plane that he could use to go travelling with his family and luggage. The C-Wolf has been designed for a multitude of purposes, from maritime surveillance to anti-poaching and leisure flights. Andre Labuschagne, Marketing Consultant for Vliegmasjien, described the C-Wolf as a double cab SUV for the skies, or an Aerial Utility Vehicle (AUV). In terms of competition, the C-Wolf aims to have more expansive mission capability than for instance a Cessna Caravan but at reduced cost (around $500 000 for the civil NTCA version and $1 million for the military version).

Initially the commercial C-Wolf version will be produced, but as Vliegmasjien envisions the aircraft being used for a multitude of roles, it is also aiming to produce the military M-Wolf (‘Induna’) and, at a much later stage, the unmanned U-Wolf (‘Tokoloshe’). This aircraft has been designed with military missions in mind and has provision to mount weapons in its pontoons, with ammunition being fed from the fuselage, as well as sensors and radars in its nose. Options include a weather radar, infrared camera etc.

Labuschagne told defenceWeb that the C-Wolf has a launch customer and that Vliegmasjien is planning for low scale production only, with capacity for around one to ten a year, but if the company received a big order it would find a partner to work with to meet demand. The aircraft, shown in mock-up form at AAD 2012, generated a significant amount of interest when it was exhibited there – Vormbaum said the United Arab Emirates had expressed interest for 20 units once the aircraft was flying. Labuschagne stated that he was confident the aircraft would sell itself once it was in the air.

Funding has been coming entirely from Vliegmasjien, although the company was invited to apply for some government funding and is still in discussion with the Department of Trade and Industry on this matter. However, Labuschagne said that the aircraft could be funded in totality by Vliegmasjien.

Although Vliegmasjien is driving most of the C-Wolf’s development, it has contracted some outside assistance and expertise. For instance, Aeronautical Engineer Francois Jordaan did the structural design of the aircraft and the Council for Scientific and Industrial Research (CSIR) will conduct flutter testing on the tail. Flight Test Engineer, Barry Zaayman is contracted to ensure best practice design compliance and will also be involved in all phases of test flying and systems refinement whilst Aircraft Certification Services cc has been contracted to ensure aviation regulations such as the US FAA’s FAR Part 23 airworthiness standards are met.

The aircraft

The design of the C-Wolf went through several different iterations as Vormbaum improved the design, finally settling on a high wing, T-tail pusher propeller layout with canards and pontoons. Wind tunnel simulation was used to verify and refine the concept. The boat hull and pontoons are based on those of jet skis. As the latter are designed to be load-bearing structures, they could carry external cargo or be fitted with cannons/machineguns for the military role, Vliegmasjien said.

By having canards and small wings attaching the pontoons (the latter wings contribute 12% of lift), the aircraft’s T-tail could be made relatively small while the pontoons/wings were designed to generate ground effect at low altitude, further boosting take-off and landing performance. This is further assisted by large (3mx0.5 m) double Fowler flaps: take-off distance will be less than 280 metres.

The C-Wolf will have an empty weight of around 900 kg and a conservative maximum take-off weight (MTOW) of around 1700 kilogrammes. Between six and seven people would be comfortable, although Vliegmasjien said eight could be squeezed into the cabin. By removing the seats, it becomes a versatile transporter, with a total interior volume of 5900 litres. There are various luggage spaces in the C-Wolf, including in the pontoons, under the seats and in the tail boom under the engine. The design also allows for a small porta-potty and kitchenette to be fitted for long range flights.

The C-Wolf has been designed to be tough and durable for remote bush operations and has various built-in safety features, such as a triple canopy ballistic parachute, stall-resistant canard configuration and cockpit escape hatch.

The structure has been designed for damage tolerance and consequently features Kevlar fuselage components. Most of the C-Wolf is made out of composites such as glass fibre, carbon and Kevlar – for instance all flying surfaces are carbon fibre while the landing gear has uni-directional glass fibre suspension blades.

The landing gear will be able to extend and retract within five seconds using an electrical system. Twin calliper stainless steel disc brakes, reverse thrust and an air brake using a split rudder section will bring it to a stop quickly, even on wet runways or water. A sacrificial plastic strip under the fuselage will allow the aircraft to land with retracted gear without incurring much damage. As the C-Wolf has been designed as a rugged bush plane, it features large 8.50-6 inch tyres suited to rough landing strips.

The 3.2 litre V-6 turbocharged Adept 320T engine is a key part of the C-Wolf. It provides high power for light weight (320 horsepower and 320 pound weight) while its use of automotive fuel will bring down operating costs. As the engine is geared, it allows for a large, five-bladed propeller that turns relatively slowly (1 500 rpm) for low noise during cruise – noise levels are targeted to be low enough to fly without headsets in the cabin. The C-Wolf’s propeller is manufactured by MT Propeller in Germany and designed specifically for use with the Adept engine and the C-Wolf airframe.

Vliegmasjien, the first customer for the Adept 320T, has received its engine and is working on fitment and cooling with Adept Airmotive. Although the C-Wolf has been designed for the Adept engine, Vliegmasjien said it could accommodate other power plants, if requested. To fulfil the maritime surveillance role, two small and lightweight turbofans could be mounted on the pontoons as an emergency power source in case of engine failure while out at sea. A tank containing turbine oil would mix with the automotive fuel to run the turbofans.

As a responsible entity that cares about the planet, Vliegmasjien’s Adept engine has been specifically configured to accept a catalytic converter to further limit CO2 emissions without any loss in performance.

The C-Wolf has been designed to make refuelling a simple process and instead of clambering up to the top of the aircraft to gravity refuel the tanks in the wings, the C-Wolf will have a refuelling station in its starboard pontoon which will contain a small transfer tank and a pump to pump fuel into the wings. As the fuel will flow to a single feeder tank, it will make water drain-off a simple procedure.

There is enough fuel capacity to give the aircraft 16 hour endurance and range of more than 3 500 km, but Labuschagne emphasised that these are very conservative estimates.

The vast majority of the C-Wolf is locally designed and built with relatively few imported components. Sports Plane Builders assisted with some of the initial composite work, but the rest is being done in house by Vliegmasjien. Instrumentation will be mostly supplied by Garmin and the aircraft will feature a glass cockpit with large colour displays with design and fitment of all electrical systems managed by I5-Technologies.