Air-to-Air refuelling capacities are rare, the western world relies on the US
All over the world armed forces are looking for air-to-air refuelling options. Europe just want to implement a EU-tanker fleet, different member countries “of the willing” should buy and provide this capability. But also inside NATO there is a growing need for that. The only country with sufficient capabilities and numbers of available airplanes is the US. Their new workhorse will be the KC-46A PEGASUS (on a Boeing B767 airframe). In the past 65 years Boeing delivered 2,000+ tankers. The KC-46A will replace the KC-135 tanker of the US Air Force (USAF).
At the moment there are six test airplanes, with 1,600+ flight hours and 1,200+ contacts (dry & wet). The delivery to the USAF should begin end of 2017. In the end, 179 KC-46A will be built for the USAF – 34 are on contract (1st three LRIP lots). 22 are currently in assembly. In 2015 also Japan selected the KC-46A, a contract for four through the USAF is expected soon. Worldwide over 1,060 B767 are in commercial operations, with a big service support network.
The configuration for the Multi-role combat capabilities involves a 6th gen fly-by-wire boom (1,200 gallon/min., designed by Boeing) and two wing air refueling pods (by Cobham) and on centreline drogue system (each 400 gallon/min.; with 212,000 pounds of fuel all together), self protection and defensive systems (Northrop Grumman IR countermeasure, RF warning, NVIS lighting, flight deck armour). At tests the highest fuel transfer was 1,365 gallons/min. But the KC-46A can not only fulfil air-to-air refuelling operations, but also cargo (e.g. 18 463L pallets, 7,800 cubic ft cargo volume), passengers (58-200 PAX) and MedEvac (54 patients, six integral litters as a basic configuration, 200 max) as well as serve as a relay for communications. The boom and the wing pods can be used at the same time (theoretically for up to three airplanes, but normally only two will be refuelled), the plan is that the KC-46A will be certified for 64 receivers. So far no receiver is certified, there were just tests with different platforms. The receiver qualification will achieve level 2 before deliveries starts, phase 3 will be done afterwards by the USAF. In a first step 18 receivers should be qualified. Four IR-lights at the front landing gear will allow night operations in total darkness with all lights out. The system was invented by Honeywell. Also a new invention are the pilot director lights (PDL) by Boeing. They are fixed on each side under the belly and will guide the receiver in total darkness.
Receiving pilots have to wear night vision goggles (NVG). Also the pods have day/night lights for guidance. The boom is removable for storage, maintenance or storage. And a large cargo door allows to change setups very easily and fast (<2 hrs).
The cockpit is a modern B787 glass cockpit layout with extra radios, Link 16, threat warning system and the pilots can view the refuelling operations. The air refuelling operator station is just located behind the cockpit and offer two workstations. One can also be used as a instructor station with override capabilities. Everything is shown via modern camera systems and big screens. The airplane offers a very high level of automation, to reduce the crew’s workload, so they can concentrate on their tactical role.
All information of the subsystems (Link 16, Electronic Battle Order, Low Date Rate Intelligence Broadcast Radio and the defence systems) are brought together by the Tactical Situation Awareness System (also a new device by Boeing). This also should bring the workload down and give the crew a better situational awareness. A crew normally consist of three, two pilots and a refuelling operator. The operator workstation uses 3D screens, so the operators have to wear 3D goggles. All displays in the cockpit are NVG capable and the special screens are coming from Rockwell Collins. The combat turn time is 1 hour according to Boeing.
According to Boeing the hard- and software is in the final version, but there is still a lot of testing for the certification to do. So far the program is behind in the planning and certification, but production is running like planned, so once delivery starts, they should be able to go back to original planning’s. FAA certification will be done by the end of the year, only then the delivery to the USAF can start.
The simulations systems (pilots and boom) are coming from Flight Safety, the maintenance simulator from Boeing.