Embraer has frozen the configuration of its KC-390 tanker/transport and plans to begin the joint definition phase in May, after the Brazilian air force - which is paying for development - has made the final decisions on the major suppliers.
Photos and graphics: Embraer
Myself, Steve Trimble of Flightglobal and John Reed of military.com got a chance on Feb. 22 to look over the full-scale cabin mockup in Hangar X-30 at the air force's CTA (Comando-Geral de Technologia Aerospacial), adjacent to Embraer's plant in Sao Jose do Campos.
The KC-390 is a big aircraft; the biggest Embaer has designed and bigger than the aircraft it is being developed to compete against - Lockheed Martin's C-130J. The cargo compartment is 17.75m long, compared with 16.9m for the stretched C-130J-30; 3.45m wide (vs 3.12m); 2.9m high forward of the wing (vs 2.74m) and 3.2m aft of the wing to make it easier to load/unload vehicles via the ramp.
One unusual feature of the mockup which we could not understand and for which I don't yet have a full explanation - a movable pressure bulkhead that retracts garage door-style into the roof and descends to seal the cargo cabin. When down, this sloping bulkhead reduces compartment length to 12.78m at the ceiling. We couldn't think of another airlifter with this feature.
The KC-390's design has changed significantly since 2007, when Embraer first revealed its studies of a military airlifter, then called the C-390, based heavily on its Embraer 190 regional airliner. At that point, using the wings, tail, engines and avionics of the E-190, the aircraft had a design payload of 19 tonnes.
C-390 (left) vs KC-390
Today, the KC-390 is an all-new aircraft with a design maximum payload of 23t, comfortably exceeding the C-130J's 21.8t. Range is 2,600nm with a 14.7t payload, 2,000nm with the 19t required by the Brazilian air force, and 1,400nm with the full 23t. Maximum cruise is Mach 0.8 and altitude 36,000ft.
Recent changes to the design have included increasing wing span in response to customer requests that the KC-390 be able to refuel helicopters, as well as fighters. This requires the ability to refuel at speeds down to 120kt and altitudes below 10,000ft. Wing span is now 35.06m.
As a tanker, the KC-390 has two underwing hose-and-drogue pods and a refueling probe (or receptacle). Some potential customers want to equip the aircraft with a refueling boom. Embraer is looking at a removable boom that could be mounted on the ramp, but hasn't settled on a workable design yet.
The KC-390 is scheduled to fly in mid-2014 and enter service with the Brazilian air force in 2016, and Embraer says the program is on track. It's hard not to walk around the mockup and think about the challenge Embraer has taken on developing an aircraft of this size and capability - but the company says it's aware where the risks are and has taken steps to invest early in reducing them.