Light fantastic

Calidus, an Emirati industrial machinery and equipment company located in Abu Dhabi, unveiled its new B-250 light attack aircraft on the first day of the Dubai Air Show, after a campaign of teasing advertisements. Jon Lake reports.

Calidus originally laid down the specification for a carbon fibre light attack and trainer aircraft in 2015 and commissioned Brazil’s Novaer to design and produce the aircraft.
The resulting B-250 was claimed to be “the first military fighter ever developed in the UAE”, although the aircraft was actually co-developed with and designed by Novaer.
Novaer’s Hungarian-born chief designer, Joseph Kovács, working under the leadership of technical director, Marcelo Ramon Ferroni, designed the B-250 to an unusually tight deadline.
“Novaer conceived, designed and manufactured a complex and sophisticated aircraft, all carbon fibre, and flew the first prototype only 25 months after the start of work,” explained company CEO, Gracillano Campos.
The B-250 programme involves suppliers from all over the world, including Brazil, Canada, the USA, the UK, Sweden, France, Germany, Italy and Switzerland. US company, Rockwell Collins, is a strategic partner in the project, supplying the Pro Line Fusion on-board avionics system.
All intellectual property rights in the B-250 belong to Calidus, however, and the aircraft is to be built in the UAE, where the company has already started development of a production complex in Al Ain. It claims that this will become a regional hub for aerospace industry excellence, capable of “very high production rates”.
Hamdan Abdulla Al Shkeili, Calidus chief software engineer, said the aircraft has already generated significant interest among regional and international air forces, and emphasised that its performance characteristics make it suitable for the light attack, close air support (CAS), intelligence, surveillance and reconnaissance (ISR) and trainer roles. He added that it had been designed from the ground up to address these requirements, rather than being an adapted trainer or civil aircraft. He also claimed that the aircraft would be competitively priced.
The UAE Air Force and Air Defence already operates a fleet of Iomax Archangel light attack aircraft and, therefore, does not seem to have an obvious requirement for the B-250, although export prospects in the wider MENA region may be quite good. Al Shkeili explained that the UAE national markings on the aircraft in the Dubai flying display were to: “reflect the aircraft’s parentage and not its customers”.
In fact, there were two B-250 prototypes at the Dubai air show. The first (PR-ZNT) appeared in the daily flying display, while the second (PR-ZNU) was shown in the aircraft static park, next to Calidus’ demonstration tent and simulators.
A close resemblance between the B-250 and the Tucano is, perhaps, not entirely coincidental, since the B-250’s designer, Joseph Kovacs, had previously been responsible for the Neiva T-25 Universal aerobatic trainer and had led the design of the Embraer T-27 Tucano.
After leaving Embraer, Kovacs designed a two-seat aerobatic touring aircraft known as the Kovacs K-51 Peregrino, and redesigned the US Aircraft Corporation A-67 Dragon light attack aircraft into a tandem-seat turboprop, which also bore a resemblance to the Tucano. At Novaer, Kovacs helped develop his own K-52 design into the T-Xc basic trainer (now known as the N-210 Sovi) and a four-seat civil derivative known as the U-Xc Pilgrim.
Originally formed in 1998 by the late Luiz Paulo Juanqueira, former head of Embraer’s equipment division, Novaer began as an aircraft component supplier, rapidly becoming the prime contractor for the landing gear of the Super Tucano and also working on the design of the Eviation Jets EV-20 business jet (the former VisionAire Vantage), before starting work in earnest on its own aircraft programmes.
The B-250 is larger but lighter than the similarly configured Super Tucano, thanks to its innovative carbon fibre structure, which also allows for more accurate manufacturing and cleaner, lower drag aerodynamic surfaces. Calidus claims that the aircraft enjoys superior performance compared to the A-29 Super Tucano.
“It is the first aircraft in this category to be totally made of carbon fibre,” said Al Shkeili.
The B-250 is powered by a 1,600shp Pratt & Whitney PT6A-68 turboprop driving a four-bladed Hartzell propeller. This is the same engine/airscrew combination as is used by the Textron AT-6 Wolverine. The Super Tucano and Pilatus PC-21 use the same engine but with a smaller radius five-bladed prop, a quieter but less efficient solution.
The fully pressurised tandem cockpits are less steeply stepped than those of the Super Tucano, but are claimed to provide the most comfortable and advanced cockpit environment in the turboprop light attack category, with a Rockwell Collins Pro Line Fusion on-board avionics system. The crew sit on Martin Baker zero-zero ejection seats.
The aircraft is fitted with a rugged landing gear for use on rough and semi-prepared airstrips.
The large ‘wet’ wings have a more highly swept leading edge than some of the B-250’s competitors, and are fitted with six hard points for weapons carriage, with a further centreline pylon for the carriage of an external fuel tank or more weapons.
At Dubai, the static aircraft carried seven Tawazun Mk 82 P3 GPS-guided bombs (with two bombs on twin carriers on the central under-wing pylon) and with South Korean seven-round LIG Nex1 LOGIR imaging infrared precision rocket pods on the outboard pylons.
Avibras Skyfire-70 and Equipaer 70mm rocket pods and Halcon Systems DS-16 smart munitions were displayed adjacent to the aircraft.
The official Calidus B-250 brochure listed a warload of four GBU-58 Paveway II 250lb laser-guided bombs, with two AIM-9 Sidewinder IR-homing AAMs and a single drop tank.
An L3 Wescam MX-15 HDi electro-optical/infra-red turret is mounted under the forward fuselage – though this was originally carried under-wing on the first prototype. It is controlled using a sidestick controller in the rear cockpit. The aircraft is also fitted with a fuselage-mounted 30-round chaff/FLIR dispenser.
The B-250 has a 560nm (1,037km) radius of action, flying at 250kts in the attack role, or a 1,180nm (2,185km) radius at 280kts in surveillance configuration, with a sensor turret and three fuel tanks. Ferry range is 2,400nm (4,445km). Mission endurance is up to 12 hours. Calidus has quoted an operating cost of less than $1,200 per flying hour.
The B-250’s maximum level speed is 301kt (557km/h) and the service ceiling is 30,000ft. Maximum payload is 3,960lb (1,796kg), or about 660lb (300kg) more than the rival Super Tucano.
The B-250 has been referred to as the Bader (the Arabic name of a species of Falcon) or as the Bader-250, but reports that there would be a formal naming ceremony at Dubai proved unfounded. Calidus is the genus name of a type of Peregrine Falcon, and broad hints were dropped that something Falcon-related was likely to be chosen for the aircraft.
There was a formal launch of the aircraft at Dubai, attended by the Brazilian Air Force commander, Air Lieutenant Brigadier Nivaldo Rossato, and the chief of staff of the Brazilian General Command of Support (COMGAP), Major Air Brigadier José Augusto Crepaldi, together with Brazil’s Secretary of Defense Products, Dr Flávio Augusto Correa Basílio, and the director of the defence products department, Air Brigadier Paulo Roberto de Barros Chã.